Waitt Institute Re-Navigation Rpt

Nutter and Associates, LLC

Re-‐Navigation Research

Christopher G Nutter

September 09

Nutter and Associates Consulting

2009 Waitt Institute for Discovery 2

Waitt Institute for Discovery

Re-‐Navigation Report

Nutter and Associates, LLC Research by Christopher G. Nutter and Michael F. DiBello



Acknowledgements

The authors and principal researchers, Christopher G. Nutter and Michael F. DiBello, gratefully thank the

Waitt Institute for Discovery for their exceptionally professional guidance, assistance and total support

for this research. Without their commitment and encouragement this project would likely have not been

completed.

We want to thank, and extend our professional respect, to all of our published colleagues before us, who

researched and investigated this accident for decades, and who contributed an important body of

knowledge and understanding to this circumstance of a historical missing aircraft. The dedication and

tireless efforts from these authors and researchers set a very high standard.

Finally we’d like to appreciate and recognize the sacrifices made by our families as we embarked on this

enormous task to review more than 71 years worth of research and evidence. The challenge was worthy

of our full commitment. The support from our families and our Research Team at the Waitt Institute for

Discovery was critically important to sustain the effort.



Table of Contents

Acknowledgements ......................................................................................................................................1

Acknowledgements ......................................................................................................................................3

Part I. Executive Summary, Work Scope and Background Information ........................................................7

Executive Summary ......................................................................................................................................7

Scope of Work.............................................................................................................................................10

Data Sources...............................................................................................................................................11

Multi-‐Source Integration (MSI) Technique..................................................................................................11

Research Reviews .......................................................................................................................................11

Definitions...................................................................................................................................................13

Historical Perspective .................................................................................................................................13

Time Reference ...........................................................................................................................................15

Radio Call Log .............................................................................................................................................17

Part II. Navigation Paths -‐ Lae to Howland Island .....................................................................................19

General Flight Path Reconstruction ............................................................................................................19

Methodology.......................................................................................................................................... 19 Overview -‐ Flight Paths A, B, and C.............................................................................................................20

End-of-Navigation Point ........................................................................................................................ 22 EON Locations ...................................................................................................................................... 23 Path Depictions ..................................................................................................................................... 23 Path C – Initial Discussion..................................................................................................................... 24

Detailed Fuel Consumption Analysis...........................................................................................................27

The Cambridge Fuel Analyzer............................................................................................................... 28 Sperry Gyro Horizon.............................................................................................................................. 34 Appendix 1 Excerpt – Review and Summary ........................................................................................ 35 Fuel Consumption and Time Remaining From All Analyses ..................................................35 Fuel Remaining Implications.................................................................................................36

Part III. Detailed Flight Analysis ..................................................................................................................37

Validated Statistical Data ...........................................................................................................................37

Winds .................................................................................................................................................... 37 Speeds – Aircraft and AE Performance ................................................................................................ 38 Flight Modeling – Lae to Howland Island .............................................................................43

Improved Accuracy................................................................................................................................ 46 Performance Specification Challenges........................................................................................................46



“Speed 140 knots…” ............................................................................................................................. 47 Flight Data -‐ AE Natal to Dakar ..................................................................................................................49

Position and Time.................................................................................................................................. 49 En route Weather – Overcast or Undercast .......................................................................................... 50 Aircraft Fuel Load .................................................................................................................................. 51 In-Flight Speed and Performance ......................................................................................................... 52 Comparing Natal-Dakar (St. Louis) and Lae-Howland .......................................................................... 52

Part IV. Detailed Flight Path Navigation and Position Reporting ..............................................................53

Howland Island Coordinates.......................................................................................................................53

For an arrival short of Howland, this only adds to the challenge of visual acquisition. Geodetic Datums .54

Specific Flight Path Navigation Summary – Lae to Howland Island ...........................................................54

Lateral Navigation – Lae to Howland Island.......................................................................................... 54 North of Howland Island.............................................................................................................................55

Position Reporting ......................................................................................................................................56

The 0418 GMT In-flight position report.................................................................................................. 56 The 0519 GMT In-flight position report anomaly ................................................................................... 56 Coordinate Transposed.........................................................................................................56 Time Error .............................................................................................................................56

The 0718 GMT In-flight position report.................................................................................................. 57 The 1030 GMT Visual Sighting of Nauru Island Lights ......................................................................... 57 “A Ship in Sight Ahead” ........................................................................................................57

The 1745 GMT In-flight position report.................................................................................................. 59 The 1815 GMT In-flight position report.................................................................................................. 59 Aircraft Position – Report Correlation ..................................................................................59

Fatigue and Human Factors .......................................................................................................................60

Celestial Navigation....................................................................................................................................61

Position Report Time and Corresponding Celestial Opportunities ........................................................ 62 A Line of Position Approach Unlikely ..........................................................................................................65

Sun Rise and the LOP ..................................................................................................................................65

Part V. The Final Search Grid .....................................................................................................................66

Search Grid Orientation ..............................................................................................................................66

Final Search Grid.........................................................................................................................................67

Standard Grid ........................................................................................................................................ 67 Bathymetric Grid.................................................................................................................................... 68

Search Strategy Considerations ..................................................................................................................69

Debris Field ........................................................................................................................................... 69 In Situ Documentation ........................................................................................................................... 69

Aircraft Views and Dimensions ...................................................................................................................69

Dimensional Data .................................................................................................................................. 69 Exemplars ............................................................................................................................................. 72



Prior Work Review ......................................................................................................................................73

Long, Elgen M. and Marie K.................................................................................................................. 73 Swenson, G., Culick, F.E.C. .................................................................................................................. 74 Safford, Laurance.................................................................................................................................. 75 Nesbit, Roy............................................................................................................................................ 76 Pellegreno, Ann Holtgren ...................................................................................................................... 78 Finch, Linda........................................................................................................................................... 79 Strippel, Dick ......................................................................................................................................... 79 Gillespie, Ric ......................................................................................................................................... 79 CDR Thompson, Commanding Officer, Itasca ...................................................................................... 80 Hewlett Schlereth .................................................................................................................................. 81 Earhart, Amelia...................................................................................................................................... 81 Signal Strength and Distance................................................................................................................ 81

APPENDIX ...................................................................................................................................................83

Abbreviations..............................................................................................................................................83

Search Grid and Scenarios ..........................................................................................................................83

Reference Grids...........................................................................................................................................84

Fuel Remaining ...........................................................................................................................................85

Fuel Consumption .......................................................................................................................................85

Aircraft Gross Weight .................................................................................................................................87

Fuel Consumption and Time Remaining From All Analyses ........................................................................88

“…Gas is Running Low…” ............................................................................................................................89

Engine Specific Fuel Consumption (SFC) Detail ...........................................................................................89

MSI Analysis (Multi-‐Source Integration) .....................................................................................................93

Conclusions for Fuel Consumption..............................................................................................................93

Possible Impact Areas.................................................................................................................................94

Search Considerations ................................................................................................................................96

Effects of Significant Lateral Deviation North of Path C ........................................................................ 96 Conclusion............................................................................................................................................. 96

Appendix 2 ..................................................................................................................................................97

Search Grids and Grid Coordinates ...................................................................................................... 97



Part I. Executive Summary, Work Scope and Background Information

Executive Summary

This research was designed to conduct a detailed assessment of the body of foregoing World Flight

research, critically review evidence in prior related works, validate or critique those works, and localize

future search options. A reduction in the planned search area would enhance the project by reducing

search time on station.

Approaching this task as a location of a lost aircraft, and definition of a probable search area, required

understanding, to the fullest extent possible, the exact possible flight paths, profiles, speeds, flight times,

fuel consumption, and pilot behaviors. Specifically in this case, these factors would determine flight time

endurance remaining upon arrival in the Howland area – directly related to where the aircraft could be

located. With little direct information on any of these factors, and the importance of accurate

assessment, this information had to be created from widely disparate sources, research, and analysis.

A detailed review was conducted of at least ten authors writing directly about the World Flight, more

than a dozen reports, and more than 8,000 pages of data associated with the World Flight attempt.

Other documents examined included the entire Amelia Earhart Papers of the George Palmer Putnam

Collection of 2,221 images from the Purdue University e-‐archives; Lockheed Electra and period aircraft

operating manuals; meteorological and oceanographic data including the Lae-‐Howland geographical

climatology; the effects of the Northern Equatorial Current, and Northern Equatorial Counter Current in

the Howland area; and other authors/pieces with various theories about the disappearance of Amelia

Earhart and Fred Noonan.

Aerodynamic engineering data and aircraft performance were examined in great detail, from many

sources and authoritative records. Aircraft performance is a major, critically important variable in this

analysis, and largely determines the vertical and lateral flight profile from Lae to Howland Island.

Amelia Earhart’s collection of flight notes, biography, life events, and her career in aviation were closely

studied to gain insight into her motivations and beliefs. Perhaps most important, we wanted to

understand Amelia’s behaviors -‐-‐ how she planned missions, flew aircraft, thought about flying them,

and how she actually conducted her flights throughout her career in the air.

Recreating the Lae-‐Howland flight segment, using as much hard data and facts as were available, was

critical to meeting research objectives. A faithful re-‐creation based on fact was the primary objective,

and offered the best chance to accurately locate the aircraft.



Three possible flight paths were defined and evaluated, each terminating in a high confidence, End-‐of-‐

Navigation point. Among the three paths, one path appears most likely (Path C), with a very high

confidence End-‐of-‐Navigation point; one path is unlikely (Path A); and one is possible but with a lower

confidence that it was executed (Path B).

The highest confidence Path C results from a rigorous path recalculation, aerodynamic performance and

fuel consumption assessments, with significant cross-‐validation of results and conclusions. Error

sensitivity analyses were performed on results for variable wind velocities, wind directions, and fuel

consumption.

A Search Grid was constructed around this Path C End-‐of-‐Navigation point to accommodate terminal

area maneuvering that was inferred from aviation experience, and application of the most likely

behavior for Amelia Earhart and Fred Noonan, on July 2, 1937.

The search grid was initially oriented, and modified, as shown in Appendix 2, further refining

Autonomous Underwater Vehicle search strategies. Several iterations of the grid with the Search Team

resulted in the final search grid included in this report.

Previous estimates of position for Amelia Earhart and Fred Noonan’s Electra include

• Northwest of Howland Island at 375nm +/-‐100nm (Safford)

• 425sm southeast of Howland at Gardner Island (Gillespie)

• North of Howland Island at 52nm (Long)

• On islands of New Britain, Mili Atoll (Marshall Islands), Saipan (Various)

• Northwest of Howland Island within 30 miles (Nesbit)

The following are among higher confidence data that support analyses

• The fuel load of the Electra leaving Lae was likely between 1080-‐1100 US gallons.

o Chater reports the fuel load at 1100 gallons.

o Collopy reports the fuel load at 1100 gallons.

o Swenson and Culick calculate the fuel load at 1080 gallons.

• Thunderstorms were forecast in at least two weather reports from Hawaii, at 250-‐300 miles east

of Lae, and Amelia received one of these reports before leaving Lae. The second report was

broadcast from Lae, to AE, during the first 7 hours of the mission.

• The Electra departed Lae at 0000 GMT.

• Of thirteen position reports made by Amelia Earhart from Lae-‐Howland, only two included a

latitude and longitude position, and one of those is potentially in error in time and/or location.

o This is unusual given Fred Noonan’s experience with making detailed position reports on

South Pacific proving flights with Pan Am in 1935.

o Before joining the World Flight, Fred wrote about the importance of complete position

reports, including latitude and longitude, air and ground speeds, wind direction and

speed, and outside air temperature, in a post-‐flight report following one of these trips.



• The Lae-‐Howland reporting history is also unusual and unlike that accomplished on the Oakland

to Honolulu, first leg attempt.

o On this initial attempt, Amelia made 9 position reports, 4 with position

latitude/longitude data, and on which Fred’s log shows approximately 35 celestial

and/or navigation fix computations taken en route.

o “…In all cases [Oakland-‐Honolulu initial World Flight Attempt] Earhart provided dead

reckoning positions. Of the four documented positions, three were provided with times,

but the wording provided by the USCG Hawaiian Sector leads to some ambiguity as to

when Earhart stated these positions. Interestingly, all four messages indicate that the

positions provided were well prior to the actual broadcast times. [The aircraft is beyond

the waypoint reported]. Based upon this analysis, one can easily speculate that Noonan's

method was to project future positions via dead reckoning, and provide that information

to the pilot sometime prior to the radio broadcasts. In no instance does Earhart provide

timely information, nor does she provide an actual navigational/celestial fix and time of

the fix to help constrain exactly where the plane was.”1

o “In summary [Oakland-‐Honolulu initial World Flight Attempt] Noonan made use of seven

radio bearings, 14 star/planet LOPs (of which nine were used for navigational fixes), and

the plane made only four course corrections. Analysis of the flight path versus weather

maps produced after this date show major concurrence with the winds aloft patterns. It

is clear that the navigator’s major responsibility was to monitor the progress of the

flight, and to suggest course corrections only when deviations from desired flight path

became too extreme. Use of projected, future DR positions allowed Noonan to check his

forecasts vs. later navigational fixes to update his speed and direction over the ground,

and to offer approximate positions, when necessary.”2

• Fred Noonan may have used this technique, if only partially reported by Amelia Earhart, on the

Lae-‐Howland segment. There is no evidence to support that Fred functioned differently on this,

his most difficult segment, than on prior segments. The lack of reporting integrity and

consistency may be understandable in that throughout the World Flight, position reporting was

infrequent, and accomplished mostly on the Lae to Howland segment.

• From AE’s aircraft performance and re-‐calculated time of arrival at waypoints, compared with

the time AE reported those waypoints, there is behavioral consistency in the technique outlined

above.

o This helps to characterize the reasonableness of these comparisons, understand the

probability associated with each path, and assess the accuracy of navigation.

• Of note is that at 1745 GMT, AE reported “about 200 miles out.” This was a position likely

provided by FN using celestial fixes throughout the night of good visibility, made from excellent

celestial bodies available, and therefore, an accurate position.

1 Randall S. Jacobson, Ph. D., The World Flight, First Attempt, Oakland to Honolulu (TIGHAR.ORG, 2006). 2 Ibid.



o The aircraft’s distance from the 1937 Howland Island coordinates at the time of this

report is 204 nautical miles, according to the Path C re-‐calculations.

o The report and the position occur at AE’s typical reporting time of 15 and 45 minutes

past the hour.

o This appears that at 1745, the Electra was on track and on course to Howland, and FN

calculated their position with good accuracy for 1937 equipment and methods.

This level of accuracy, while not routine in that period, was certainly possible.

o This creates the possibility that something happened in the last 200 nautical miles

distance to Howland Island.

• After 0718 GMT, position reports were made in the blind.

o Amelia had no pre-‐arranged communications between Lae and Itasca.

o There were no arrangements for communicating with Ontario.

o There were no arrangements for communicating with Nauru Island.

• Aircraft aerodynamic performance was established with a high degree of confidence through

data integration from many sources, and with consideration for pilot behavioral performance.

• While radio strength is not entirely related to distance, strengths associated with the final few

reports are the only indication of possible relative terminal area position.

Our research concludes for Path C, the most likely path, an End-‐of-‐Navigation point 35-‐28nm southwest

of Howland Island, bearing 067 degrees to the 1937 position of Howland Island. A water entry area is

shown for three fuel exhaustion scenarios (Swenson and Culick, Nutter, and Kelly Johnson) which plot

theoretical points of fuel exhaustion following AE’s arrival at the End-‐of-‐Navigation point, as a function

of fuel remaining at the End-‐of-‐Navigation point. These comprise theoretical position boundary limits,

assuming AE conducted the search pattern depicted, throughout terminal maneuvering in search of

Howland and Itasca. A high confidence water entry area is shown for the time 2013 GMT until 2100

GMT, likely from either fuel exhaustion, or from controlled flight into terrain, resulting from loss of

situational awareness, fatigue, or abnormal mechanical circumstances. The maximum fuel remaining at

1912 GMT is computed at 123 gallons, and with a failure of the Cambridge Fuel Analyzer (discussed later

in this report), the fuel remaining may have been 63 gallons, enough for approximately 90 minutes flying

time.

Fuel consumption is discussed extensively later in this report. It is very likely that fuel exhaustion occurred

between 2013 GMT and 2100 GMT.

Scope of Work

Tasking for this report was to conduct an internal audit of prior research and provide assessments on the

validity of theories, methodologies, assumptions, and historical conclusions regarding the search for a

major historical artifact as disclosed by WID; critically examine previous studies; document

considerations regarding planned search strategies and if possible attempt to refine a location for The

Project, or narrow the area of interest.



Collaborate with Project researchers.

Conduct research, audits, and review of other previous work and assessments.

Investigate the “accident” Project, in terms of standard accident investigation methodologies, and

conduct new research to achieve acceptable location assessments, narrow the area of interest, and/or

validate planned search strategies.

Data Sources

Direct evidence consists of actual aircraft performance, AE reports and flight logs, operating manual

data, and reference publication information such as the Lockheed Electra Flight Operating Manual, the

celestial Almanac Pub 249 used for celestial navigation, and data from the engine’s manufacturer, Pratt-‐

Whitney.

All other data is considered supplemental, useful and important, but subject to less accuracy than

validated, direct evidence.

Multi-Source Integration (MSI) Technique

This research employed an MSI approach to re-‐constructing relevant facts concerning the last leg of the

World Flight attempt. With MSI, facts and other data are evaluated in a manner similar to Linear

Programming, except that most relationships among parameters are not strictly numerically defined, but

rather, qualitatively related. Many of the links between data elements must be created, and created in

ways that have not been done before.

MSI is a forensic and creative approach to a data fusion process, integrating information from multiple

sources. MSI can sometimes corroborate a finding as fact, refute assertions made as fact, and provide

boundary limits on the most likely conditions and conclusions.

Research Reviews

This research methodology included an integrated study and analysis of the following publications.

Amelia Earhart, Dick Strippel, Exposition Press, Inc., 1972

Amelia Earhart, The Mystery Solved, Elgen M. and Marie K. Long, Simon and Schuster, 1999

Analysis of Amelia Earhart’s Final Flight July 2, 1937, G. Swenson and F.E.C. Culick, JPL, CIT

Cruise Report 24 July, 1937 CDR Warner Thompson, Commanding Officer, Itasca (Gillespie disk)

Earhart’s Flight Into Yesterday, Captain Laurance Safford (USN-‐R) with Cameron Warren and Robert

Payne, Paladwr Press, 2003



Finding Amelia, Ric Gillespie, Naval Institute Press, 2006

Itasca Radio Logs

Kelley Johnson Telegrams -‐ Electra test flight data and World Flight performance recommendations

Last Flight, Amelia Earhart, Quinn & Boden Company, 1937

Lockheed Report 487 -‐ June 1936 by Clarence L. “Kelly” Johnson and W.C. Nelson

Missing, Believed Killed, Roy Conyers Nesbit, Sutton Publishing LTD (UK), 2002

No Limits, Linda Finch with Donald Smith, World Flight, Inc., 1996

Radio Press News – USS Colorado

The Black Report – Richard Black, U.S. Department of Interior

The Chater Report – Eric Chater, Guinea Airways Limited

The Cooper Report -‐ Daniel Cooper, Army Corps on Itasca

The Dowell Report – Commander, Lexington Group

The Friedell Report – Captain Friedell, USS Colorado

Weather Reports from accounts by Collopy, Chater, Itasca logs and historical meteorological data

World Flight, Ann Pellegreno, Iowa State University Press, 1971



Definitions

AE – Amelia Earhart

CFA – Cambridge Fuel Analyzer

EON – End-‐of-‐Navigation point

FN – Fred Noonan

GS – Ground Speed

IAS – Indicated Air Speed

L487 – Lockheed Report 487

MSI – Multi-‐Source Integration

SFC – Specific Fuel Consumption (lb/BHP/hr)

TAS – True Air Speed

Historical Perspective

The World Flight attempt commenced at 1630 on March 17, 1937 with a departure from Oakland, CA for

Honolulu, HI. The flight departed with 947 gallons of fuel, at a gross weight of 14,000 lbs. Takeoff power

was set at 1100 Brake Horsepower (engines were rated at 600 HP per engine with takeoff power time

limited) and shortly after becoming airborne, AE reduced the power in keeping with her characteristic

“kind” treatment of engines.3

It is relevant that AE frequently gave human qualities to her machinery, particularly to engines, and

referred to them in humanistic terms. AE seemed to always endeavor to treat her equipment with

kindness, not demand “too much” from faithful engines, or push the airframe “too hard” in speed,

turbulence or during landings. She wrote, “Once aloft [from Oakland], I throttled down. Engines have

human attributes – they usually respond to kindly treatment. With a long grind before them I wished to

give mine the least possible punishment.”4

This behavior is reflected, and to some extent, governs, AE’s aircraft performance throughout her World

Flight segments, which can be generally considered “consistently conservative.”

3 Elgen M. and Marie K. Long, Amelia Earhart -‐-‐ The Mystery Solved (New York: Simon and Schuster, 1999) 56. 4 Amelia Earhart, Last Flight (Rahway, N.J: Harcourt, Brace and Company, 1937) 58.



En route to Honolulu, high tailwinds pushed ground speed at one point to 180 mph, and AE slowed to

120 mph indicated airspeed at 10,000 feet so as not to arrive before sunrise, burning slightly less than 20

gallons per hour (GPH). It was not specified if this was 20 GPH total, or per engine, but it is likely a per

engine consumption rate, for 40 gallons per hour total. This conforms to Pratt-‐Whitney engine data.

(This data point is useful for consideration of maximum endurance speed, and fuel consumption rate,

during terminal area maneuvering in the vicinity of Howland Island. In this environment, fuel

consumption rate for analysis was defined in this research as 40 GPH at 120 mph indicated airspeed.

Indicated air speed is roughly equivalent to ground speed at low altitudes, and construction of the search

grid used a 120 mph ground speed.)

FN instructed AE to begin a descent at 80 miles from Makapu. This was approximately in line with

recommendations made by Lockheed and Kelly Johnson5, to commence descents at 100-‐150 statute

miles at 200-‐300 feet per minute descent rate, using slightly less than cruise power, and approximately

maintaining cruise speed.6

This guidance is also consistent with the Electra Operating manual from an airline company, for the

Lockheed 10A Electra aircraft.

FN likely worked in nautical miles, and 80 nautical miles is 92 statute miles, within 9% of the

recommended minimum descent distance.

The flight time of 15 hours 47 minutes, over the 2410 statute miles, resulted in an average ground speed

of 152.7 mph. This was a higher speed than normally flown for long mission distances, a result of the

higher-‐than-‐anticipated tail wind conditions.

On the subsequent flight segment from Hawaii, a takeoff mishap resulted in aircraft damage requiring

repairs to the Electra, made at Lockheed in Burbank, CA. The aircraft was shipped to Lockheed via

surface vessel. This accident resulted in canceling the first World Flight attempt, and delayed the second

World Flight attempt while repairs were made to AE’s damaged aircraft. During these repairs at

Lockheed, apparently, one of the original two starboard side fuselage windows was replaced with

aircraft skin sheet metal, at approximately amidships. Comparative photographs reveal this alteration,

not considered significant to either navigation or the mission. This alteration has not been addressed in

previous research. Three aft windows remained, two on the left side at the entrance door and just

forward of the door at the navigator station, and one on the right side of the fuselage, for FN navigation.

5 Clarence L. “Kelly” Johnson and W.C. Nelson, Lockheed Report 487 Range Study of Lockheed Electra Bimotor Airplane (California, Lockheed Aircraft Company -‐ June 1936). 6 Kelley Johnson, Telegrams -‐ Electra flight test data and World Flight performance recommendations (Western Union 11 March 1937).



An aircraft and contents pre-‐shipping inventory, made by military personnel at Luke Field7, revealed two

important items. One was a collection of 11 insect collection tubes, also described by AE as about 1

meter in length with the circumference of a broom handle. These were used to collect air samples, and

specimens, en route at various places around the world, in conjunction with government and university

research8. These may be identifiable in a debris field. Second, the inclusion of 6x30 binoculars was an

indication that binoculars may have been used in the final terminal area search for Howland.

While life vests were noted, a life raft was not noted in this inventory.

Following repairs completed on May 19, 1937, NR16020 was flown to Oakland, CA on May 21, 1937,

then to Tucson, AZ; El Paso, TX; New Orleans, LA; and to Miami, FL, arriving the afternoon of May 23,

1937 for a week of final World Flight preparations.

On June 1, 1937 at 0556 local time (1056 GMT) in Miami, NR16020 departed for Oakland, CA via an

eastbound equatorial route around the world. Aboard were AE and FN.

Their first stop was San Juan, Puerto Rico. Amelia and Fred’s plan called for a flight time of 7 hours 40

minutes on this leg. AE indicates they arrived at approximately 1310 local time, at 1810 GMT, with an

approximate actual flight time for 1153 statute miles of 7 hours 18 minutes, and an average ground

speed of 157.9 mph.

References to aircraft and mission performance throughout the World Flight provide an audit trail of

characteristic and historical data concerning speeds, engine power settings, fuel consumption, flight

behaviors, human factors, fatigue management, navigation, and progress toward achieving World Flight

mission objectives.

This data provides a statistical basis to compare with re-‐calculated navigation and aircraft performance,

providing a quality assurance function that methodology is reasonable, reliable, and affords improved

accuracy.

Additional flight segments are discussed in following sections.

Time Reference

Additional central factors involved in this research were Time and Radio Schedules (transmit and receive

plans among various parties). These issues are well documented by Long, Safford, and Itasca logs. These

complexities are important to establishing an accurate timeline, which is necessary to document the

flight profile and likely end point of the mission. Resolving all time issues was critical to accurate re-‐

construction.

7 Ric Gillespie, Finding Amelia: Luke Field Inventory, CD-‐ROM (Maryland: Naval Institute Press, 2006). 8 Fred C. Meier, Department of Agriculture.



Perhaps Long said it best9, “At that point, Howland Island, and the three ships [USS Ontario, USS Swan,

and Itasca] were operating with their individual clocks set in five different time zones and their calendars

on two different days and dates. Two were set in zones where the whole hour came at the same time as

the Greenwich whole hour; two had their clocks set a half hour different from Greenwich time; the fifth,

Earhart’s, was variable and changed with her movements. With the International Date Line in the middle

of the assembled ships and stations, the system was all but incomprehensible. Any requirement that an

action be timed to occur on the hour as supposed to on the half hour, at a quarter before the hour as

opposed to a quarter after the hour, or at any specific number of minutes before or after the hour, was

wide open to misinterpretation….”

Further, Long states, “…Howland Island was using the 10+30 hour time zone –the same as Hawaii

standard time – while the Itasca was using the 11+30 hour time zone; the two were one-‐half mile apart,

but one hour different in time.

The research methodology for The Project baselined all calculations to Greenwich Time, also known as

Greenwich Mean Time (GMT) or Universal Coordinated Time (UCT).

9 Elgen M. and Marie K. Long, Amelia Earhart -‐-‐ The Mystery Solved (New York: Simon and Schuster, 1999) 165.



Radio Call Log

Below is a summary of relevant radio reports.

Report Local / GMT Time Originator Description

1 July WX 2330 GMT Itasca SFC NE 14 mph. At 9000 feet E-NE 31 mph. LONG p206. Takeoff Lae on 2 July

1000 Lae 0000 GMT Lae 1080-1150 gallons aboard.

2 July WX 0000 GMT Fleet Base Pearl Harbor CB 300 miles east. Winds E-SE 25 knots (29 mph) to ONTARIO then E-ENE 20 knots (23 mph) to Howland. CHATER Report – Large Notebook. CHATER p7-8.

WX 0000 GMT

Baro 29.89 Temp 83 deg F winds E 3. Cloudy CI CI STR CU CUMI moving from E. Sea smooth…NARU 8 AM (not clear local or GMT but assume local taken before takeoff but not received by AE since it arrived Lae at 1000 local, at takeoff), Upper Air Observation 2000 feet 90 degrees 14 mph; 4000 feet 90 degrees 12 mph; 7500 feet 90 degrees 24 mph. CHATER.

Position 1418 Lae Local 0418 GMT AE Height 7000 feet. Speed 140 knots. Everything OK. Received

by Lae. CHATER. (Speed not specified as to type).

Position 1519 Lae Local 0519 GMT AE Height10000 feet. Position 150.7 east 7.3 south; cumulous

clouds; everything OK. [Problematic report.] CHATER.

Position 1718 Lae Local 0718 GMT AE

CHATER reports this as 4.33 South 159.7 East; Height 8000 feet over cumulous clouds. Wind 23 knots. SAFFORD reports this as LAT 4 deg 33 min. LONG 159 deg 06 min. SAFFORD (p30) states “on course” at 750-795 miles. SAFFORD concludes this is at 7 minutes before sunset, 10 miles west of the Nukumanu Islands. If same course and speed held, ETA Howland should be 2100-2145 GMT. Unfortunately, SAFFORD reports Itasca did not receive this position report until after AE was overdue and missing. SAFFORD (p30.) ComHawSec reports this in post accident summary reports and message logs to ITASCA that “LAE, NEW GUINEA REPORTS LAST CONTACT WITH EARHART PLANE BY LAE RADIO WAS AT 1720 [LAE LOCAL] FRIDAY GAVE HER POSITION AS 4.33 SOUTH 159.6 EAST WHICH IS ABOUT 795 MILES DIRECTLY ON HER ROUTE TO HOWLAND 0030. (Pink tab in large notebook)

Progress Author Briand

Says he plotted this giving him 750 miles and ground speed 103 knots (118 mph). Says Lexington’s plot gave 785 miles and 111 knots (128 mph). HAWSEC reports 795 miles on course to Howland. SAFFORD.

2 July MSG from Lae via Naval Radio Tutuila to Itasca (Black) received Itasca

AE left Lae 1000 local due Howland 18 hours. LONG p207.

Clarence Williams Purdue and Harvard

Collections Flight Plan Lae-Howland 2556 miles 17 hours 1 minute.

Position 1030 GMT AE 1100-1200 GMT Nauru Island - Mr. Cude, Director of Police reported receiving radio from AE “Ship in Sight..” SAFFORD p31.

Position 1030 GMT USS ONTARIO

Mid-point plane guard [SAFFORD p 30 states this is at 1030 GMT, but in the ONTARIO LOG, it gives an “8 PM” position. If Ontario used the same local time as Lae, this equates to being on station at 10 hours mission elapsed time. If Ontario used a one-hour time zone change, they’d be on station at 9 hours mission elapsed time. ONTARIO position logged with precision as S 2 deg 59 min 30 sec / E 165 deg 20 min 00 sec. Included WX. Wind- east 15 knots. Blue sky cumulous moving from East. Amount 40%. (It was night, so Blue sky



refers to clear skies.) Visibility 40 miles. Ceiling unlimited. Conclusion – Noonan nav is dead on. SAFFORD.

SS Myrtlebank SAFFORD p 32 explains why he concludes the ship sighted was ONTARIO and not the Myrtlebank. Likely incorrect.

Position 1415 GMT Itasca

ITASCA logs “Heard Earhart plane on 3105 but unreadable through static. Chief Bellarts caught Earhart’s voice and it came in through loud speaker, very low monotone “cloudy and overcast.” (Large notebook logs)

Radio Log 1318-1325 GMT Itasca MSG from ITASCA to Com SF Div that they “heard Earhart plane at 0248 0235.”

Position 1415 GMT AE Cloudy and Overcast. S1. LONG p208.

Position 1445 GMT AE Overcast will listen on hour and half hour 3105. S2. Ibid.

Position 1623 GMT AE Partly Cloudy. S1. Ibid.

ITASCA 1625 GMT AE ITASCA “Earhart broke in on phone – unreadable.” (Large notebook Itasca logs)

Position 1744 GMT AE “About 200 miles out” request DF Steer. S3. Ibid. Large notebook Itasca logs indicate this logged at 0615 IST

Sunrise 0715 Howland 1745 GMT Sunrise at Howland (USNO data) GMT 10+30 time zone.

Position 1815 GMT AE

“About 100 miles out” request DF Steer. S4. Ibid. Large notebook Itasca logs have this as “PLEASE TAKE BEARINGS ON US AND REPORT IN HALF HOUR I WILL MAKE NOISE IN MICROPHONE – ABOUT 100 MILES OUT (EARHART SIGNAL STRENGTH -4 BUT ON AIR SO BRIEFLY BEARINGS IMPOSSIBLE.)


We must be on you. Gas is running low. S5. Ibid. This is 1+27 after sunrise. Large notebook Itasca logs have this as “KHAQQ CALLING ITASCA WE MIUST BE ON YOU BUT CANNOT SEE YOU BUT GAS IS RUNNING LOW BEEN UNABLE REACH YOU BY RADIO WE ARE FLYING AT ALTITUDE 1000 FEET. Other Itasca logs record that “Earhart is on now says running out of gas only ½ hour left…” The signal strength of this AE report is noted as “5.”


“We are circling” request DF Steer. [Controversial log record as to what was exactly said by AE]. S5+. Ibid. Large notebook Itasca log has this as “KHAQQ CALLING ITASCA WE ARE CIRCLING BUT CANNOT HEAR YOU GO AHEAD ON 7500 EITHER NOW OR ON THE SCHEDULE TIME ON HALF HOUR.” Itasca logs this as signal strength 5 on radiotelephone. Some references log as 5+.

Verbiage Doubt

Radioman Galten on Itasca logged this call from AE as “we are drifting but cannot hear you.” To CDR Thompson this didn’t make sense so he allegedly erased “drifting” and substituted “circling,” which then didn’t make sense, so CDR Thompson changed the whole thing to “We are circling but cannot see island.” SAFFORD. Itasca log says “we are circling but cannot hear you” so SAFFORD thinks perhaps CDR Thompson changed the verbiage in his final report.

Position 1930 GMT

Large notebook Itasca logs have this as “KHAQQ CALLING ITASCA WE RECEIVED YOUR SIGNALS BUT UNABLE TO GET A MINIMUM PLEASE TAKE BEARING ON US AND ANSWER 3105 WITH VOICE (sent long dashes for 5 seconds or so.)


On LOP 157-337. S5. LONG. This is 61 minutes after first “We must be on you gas is running low” report. Large notebook Itasca log has this at 2014 GMT as “WE ARE ON THE LINE OF POSITION 157-337, WILL REPEAT THIS MESSAGE. WE WILL REPEAT THIS MESSAGE ON 6210 KCS. WAIT LISTENING ON 6210 KCS. WE ARE RUNNING NORTH AND SOUTH.” Itasca logged this as signal strength 5. This is the last AE transmission in the large notebook logs which are CDR Thompson’s message logs from Itasca.

The next three audio messages are not mentioned in either LONG or GILLESPIE but only in SAFFORD, however, they are not referenced and the origin of these “documented”



messages is not known.

Radio Call 0801 GMT Next day UNK Message garbled on 6210. Received at Nauru. SAFFORD

p36 Unsubstantiated anywhere else.

Radio Call 0811 GMT Next day UNK Message garbled on 6210. Received at Nauru. ibid.

Radio Call 0822 GMT Next day UNK Message garbled on 6210. Received at Nauru. ibid.

Gillespie Bearing Analysis

From Gillespie on p 164 – If bearings from three stations (Guam, Wake, Makapu) are adjusted plus or minus azimuth values of just 5 degrees in the most likely directions, they intersect and form a centroid at about 100-200 miles SW of Howland, through which a 337-157 LOP only passes if it is displaced west of Howland by about an hour flight time (100-150 sm). Bearing variances in easterly directions intersect in areas well beyond the range of the Electra, and are therefore discounted by me. If “post crash” radio transmissions were actually made by AE in the most likely area according to the station bearings on these signals, it would mean AE was about 150sm short, flew an LOP 200 sm south of Howland and Baker Islands, and could transmit radio signals after a water ditching. All three are considered unlikely.

Part II. Navigation Paths - Lae to Howland Island

General Flight Path Reconstruction

Research requirements demanded an extensive effort.

A fundamental research strategy was centered in an attempt to recreate the aerodynamic and

environmental aircraft performance on the final flight, from well-‐established fact, well-‐founded

inference, logical and experienced-‐based assumptions, and a critical application of statistical analysis of

historical flight parameters, human factors and behaviors.

An area of inescapable uncertainty in the true location of this aircraft will always exist until a discovery is

made. This research resulted in improvements in understanding the associated flight path, mission

elapsed and endurance times, fuel consumption, and the probability for artifact detection.

Methodology

Our research methodology included a new approach to the navigation of the flight profile. Previous

works generally used averages of total distance, divided by mission time, to ascertain location.

This research took a different approach by modeling the Electra with the following references

• Flight performance data from the Lockheed 487 Report (L487)

• Kelly Johnson telegrams of calculated and actual aircraft performance, and in-‐flight test data



• Corroborated Lockheed 10A operating data, with virtually the same horsepower per pound of

aircraft weight as the Lockheed 10E, slightly less frontal area due to smaller engine cowlings,

and a Cambridge Fuel Analyzer of the type used by AE

• Data from AE Electra flights prior to the World Flight

• Historical statistical speed data from AE’s prior World Flight segments

• Validated data from Long’s wind assessments

• Swenson and Culick’s aircraft drag, speed and fuel consumption computational results

• Aircraft and engine performance from operating manuals of aircraft using the same engine as in

AE’s Electra (North American T-‐6, for example)

• Fuel consumption analysis referencing actual Pratt-‐Whitney Specific Fuel Consumption (SFC)

data for the R-‐1340-‐S3H1 engine, used by AE’s Lockheed 10E.

A software model was created in Jeppesen FliteStar flight planning software, and used to construct flight

plans from Lae to Howland via three paths. Takeoff, climb, cruise, and descent were re-‐calculated by

segments, with performance integrated manually from multiple sources. Fuel consumption was

examined by profile segments, summed across the profile, and validated from multiple source data. A

more precise, manual computational analysis of fuel consumption was made from resources, further

refining this important factor.

Overview - Flight Paths A, B, and C

Research for this report includes assessment of three principal re-‐calculated paths, Path A, B, and C as

defined below.

While each Flight Path will be examined in detail, in general, Flight Path A arrives almost everywhere,

too early, and at 1912 GMT has actually over-‐flown Howland Island by enough to possibly preclude visual

acquisition of the island, or the Itasca.

Flight Path B passes through the incorrectly reported 0519 GMT longitude position at 2 hours 18

minutes, and is then early at the 0718 GMT position report. AT 1912 GMT, this Path B arrives at the 1937

position coordinates for Howland Island.

Path B is also misaligned with navigation reporting position and time, and despite arriving at Howland

Island, no person saw or heard the Electra. Path B may have passed through the 0519 GMT reported

position, at an actual time of 0218 GMT, with these times misreported by Chater10 or Collopy.11

Reduced mission headwinds during the last 8 hours of the Lae to Howland segment, could result in Path

B beyond Howland Island. A 5-‐10nm lateral error could result in nobody hearing or seeing the Electra,

10 Eric Chater, Letter to friend Mr. M.E. Griffin, Placer Management Limited (New Guinea: /LP 25 July, 1937). 11 J. A. Collopy, Report to Civil Aviation Board (Salamaua: 28 August, 1937).



and the aircraft at a wind-‐adjusted Path B End-‐of-‐Navigation point, 20nm northeast-‐to-‐southeast of

Howland Island.

The evidence suggests that the 0519 GMT reported longitude may be incorrect.

Correcting the 0519 GMT position report in longitude, with the actual position along the E 157.0

longitude, vice the E 150.7 longitude reported by Chater12, creates Path C. This path is reasonably aligned

with all navigation reporting positions and times within 5% of the time the aircraft was at that point. Key

factors such as entering the visual horizon to Nauru Island, where AE reported seeing lights on the island,

are aligned in time and position. AE arrives slightly short of Howland Island due to what is possibly a

navigational error, or miscalculation between 200nm and 100nm west of Howland Island, between 1745

GMT and 1815 GMT. One possible error is a sunrise celestial calculation of refraction, or dip angle

computational error, of 31-‐70 nm depending on altitude at the time the fix was taken, such that “If the

correction was not made, Noonan would have calculated that the Electra was nearer Howland Island

than was the case.”13

Other errors are possible, including that FN made no errors and AE decided to descend slightly early,

perhaps to keep Howland ahead of them to facilitate visual acquisition. This behavior would not be

atypical for AE, as demonstrated on the Natal-‐Dakar segment when she turned opposite to FN’s

suggested direction.

At the 1,000 feet altitude reported by AE approaching Howland Island, AE is at the edge of a visual

acquisition range to the island and Itasca. Due to the rising sun directly ahead, visual acquisition would

require being much closer to the Island.

Lateral track errors are possible, but there is no factual data upon which to make assessments of lateral

navigation deviations from the planned course, and no evidence of lateral track error. On the contrary,

the available data indicates AE adhered well to the track from Lae to Howland Island.

While all three paths are possible, Path A may be unlikely. Path B is possible, in that it deviates south of

track for weather avoidance, and passes through the point chronicled at 0519 GMT, at an actual time of

0218 GMT. The numerals “5” and “2” could have been confused. Path C is likely.

The evidence for en route aircraft performance, mission times, position reporting, and key milestones,

are all well aligned with navigation Path C. Even with reduced second-‐half mission winds, Path C

concludes short of Howland Island, in the designed Primary Search Grid.

A final AE radio report at 2013 GMT with no further communication from AE, indicates a possible

scenario in which the Electra contacted the water during terminal area maneuvering, perhaps due to

pilot fatigue, loss of situational awareness, or due to fuel exhaustion, after 2013 GMT. A fuel

12 Eric Chater, Letter to friend Mr. M.E. Griffin, Placer Management Limited (New Guinea: /LP 25 July, 1937). 13 Roy Nesbit, Missing Believed Killed (Gloucestershire U.K: Sutton Publishing Limited, 2002) 26.



consumption analysis (updated from Appendix 1) creates an endurance window until 2100 GMT. Fuel

exhaustion between 2013 GMT and 2100 GMT is likely.

Evidence from Itasca weather reports for the morning of July 2, 1937 indicates light winds and a calm

surface. Calm seas are difficult to fly over at lower altitudes because the pilot can lose awareness of

altitude. At sea, the horizon and sea surface can blend into an uncertain mirage without sufficient detail

to visually maintain desired altitude above the smooth water surface. Unintentional contact with the sea

is a constant hazard during low altitude maneuvers over calm sea surfaces.

End-of-Navigation Point

An End-‐of-‐Navigation point (EON) was identified on each path, at 1912 GMT when AE thought, and

reported, she had arrived at Howland Island (1937 coordinates). The End-‐of-‐Navigation point (EON) is

determined by the lateral path, vertical profile dynamics, and aircraft performance. The EON point is the

commencement point for terminal search maneuvering, and construction of search grids.

Wind effects and reasonable navigation errors were then considered with terminal maneuvering to

create containment zones that comprise the Primary (west) and Secondary (east) Search Grid zones.

On the two most likely Paths, Path B and C, the effects of modified winds from 20 degrees left of the nose

at 18 knots (approximately 25% less velocity) were examined to produce an error tolerance for the case

in which AE held a magnetic course only, with no overnight wind correction applied.

• A scenario examined the effect of a wind change for the last 8.5 hours of the mission.

• A second scenario examined the effect of a wind change for the final 2.0 hours.

Reduced second-‐half winds are supported by data from weather forecasts from Hawaii, and surface

vessel weather reports in the area of the flight. Both Hawaii preflight weather forecasts contained

reduced second-‐half mission wind velocities.

Grid Search areas are containment zones accommodating these effects, which move the End-‐of-‐

Navigation point slightly east, and slightly southeast, of the original track.

Milestone waypoints for AE position reports were placed on each path at the GMT times that AE made

the report, to see where on the path, in time, these might have occurred. With consideration for

tolerances in reporting behavior, variance in position reporting, and error in fixing positions, the aircraft

locations over the earth at the times of the reports, support validation of the analysis. This helped

provide context to path construction and timing.



EON Locations

All three paths are executed based on as much factual data as possible, concluding in End-‐of-‐Navigation

points at time 1912 GMT. The location of the aircraft on each path, at this time, is shown below:

• Path A is the great circle direct path from Lae to Howland Island, with an EON bearing from the

island 066 degrees magnetic at 22nm past the 1937 Howland Island coordinates. o N 00° 54' 22.2W176° 21' 33.9

• Path B passes through the waypoint reported by Chater at 0519 (a point with discrepancies in

location and/or time), with an EON at the 1937 Howland Island coordinates. o N 00° 49' 00.0W176° 43' 00.0

• Path C passes through a longitude-‐modified 0519 GMT waypoint with an EON bearing from the

island 247 degrees magnetic at 35nm short of the 1937 Howland Island coordinates. o N 00° 40' 51.7W177° 16' 41.1

Path Depictions

The three paths are depicted below with the time of arrival at two important AE position reports. For the

0519 GMT and 0718 GMT waypoints, the aircraft could have arrived at the waypoint before the

waypoint was reported, consistent with Fred’s navigation techniques demonstrated on the Oakland to

Honolulu segment, and Amelia’s reporting of Fred’s waypoints on that flight.

While the Oakland-‐Hawaii segment revealed FN and AE waypoint arrival and reporting techniques, the

Lae to Howland segment uniquely included passage over landmasses, unlike the Oakland-‐Honolulu and

Natal-‐Dakar oceanic crossings. All three paths contain over-‐flight of good, visible island waypoints,

where checks of position, time, and fuel consumption could have been made with good precision. On

these unique segments, it is possible that a position report was issued shortly after establishing the

aircraft at the waypoint, approximately 10-‐15 minutes later, a time that also was very close to AE’s pre-‐

scheduled reporting at 15 and 45 past the hour.



Figure 1 -‐ Three Possible Paths and Initial Position Reports.

Path C – Initial Discussion

Path C is a likely path. Although it deviates south of other, more direct paths, this deviation is supported

by two weather forecast reports. One report was delivered to AE in Lae on July 1, from Navy

headquarters in Hawaii.14 AE received this report in hard copy. The second forecast arrived in Lae on July

2 during AE’s takeoff from Lae.15 This report was broadcast to AE on the hourly schedules arranged with

Lae, and throughout a period of approximately 7 hours. Both pre-‐launch forecasts were for strong and

dangerous thunderstorms east of Lae, on the direct path to Howland. The second report expanded the

area of thunderstorms from 250 to 300 miles east of Lae, and provided an updated estimate of en route

winds. While the first report contained wind estimates less than what AE reported at 0718 GMT, the

second forecasted en route winds at “…east southeast about twenty five knots to Ontario, then east to

east northeast about twenty knots to Howland….”

These winds estimates were surprisingly accurate, corroborated by AE’s 0718 GMT in-‐flight position

report that included winds, at 23 knots, and from wind reports from Nauru Island, and surface vessels.

Second-‐half mission winds were very likely at reduced velocity and from slightly left of the track from Lae

to Howland.

14 ComHawSec Fleet Base Pearl Harbor messages, (Hawaii: Headquarters, 1-‐2 July, 1937). 15 Chater, Letter to Mr. M. E. Griffin, 6-‐7.



These wind profiles were modeled by out team in the Jeppesen FliteStar software and in sensitivity

analyses resulting in establishing the search grid.

AE was well aware of the existence of hazardous weather, between Lae and Howland. In fact, weather

forecasts from Hawaii contained admonition to avoid flying through these dangerous thunderstorms. AE

previously experienced heavy weather, from Natal to Dakar, and likely heeded Hawaii’s warnings.

Fred writes, in a letter to his friend, movie actor Eugene Pallette, “…The flight from Natal, Brazil to Africa

produced the worst weather we have experienced – heavy rain and dense cloud formations necessitated

flying blind for ten of the thirteen hours we were in flight.”16

AE also felt compelled to comment on the rain, “…the heaviest rain I ever saw. The heavens fairly

opened. Tons of water descended, a buffeting weight bearing so heavily on the ship I could almost feel

it.”17

Midday cumulous buildups over landmasses, such as the island of New Britain, may have also presented

hazardous weather on the direct route to Howland Island that could be avoided with a relatively minor

deviation southeast, across very good landmarks.

From their Atlantic crossing segment, Natal to Dakar, AE and FN possibly, and intentionally, planned a

southerly deviation around New Guinea area weather, one with few penalties and several advantages.

Path C passes over Choiseul Island, the first island south of Bougainville Island. Both Bougainville and

Choiseul are prominent visual landmarks. Bougainville’s mountains exceed 8,000 feet in the northern half

of the island, but are easily avoided. Choiseul’s highest terrain is approximately 2,000 feet.

This deviation on Path C added only 42nm to the overall mission distance. The path also facilitated an

afternoon setting-‐sun celestial fix, from the left side of the aircraft, inbound to the 0718 GMT reporting

point near Nukumanu Island.

16 FN letter from Dakar, Senegal, French West Africa, June 9, 1937 to Eugene Pallette, Hollywood Roosevelt Hotel. 17 Amelia Earhart, Last Flight, 128.



Figure 2 – Path depictions and supporting Factors for Path C.



Figure 3 -‐ Pilot-‐eye view approaching the 0718 GMT position on Path C.

Only on Path C do all initial position reports in time coincide reasonably and closely with AE reported

positions in space, and they agree in time within 5%. From the Oakland to Honolulu navigation logs,

position reports were often made at some time after passing the reported position, and with the aircraft

not co-‐located with the reported position. The lag between position passage, and reporting, is

understandable in that it was AE’s first real navigation challenge working with Fred Noonan and Paul

Mantz, and there were no landmarks corresponding to reported positions and times.

AE and FN may have sought to be more precise on the Lae to Howland segment, to more closely report

positions and times. The data supports such an intention.

A more detailed analysis of Path C is contained in Part IV.

Detailed Fuel Consumption Analysis

The detailed fuel consumption analysis, Appendix 1, initially results in up to 4 hours fuel remaining, at

1912 GMT. Further analysis since publication of Appendix 1 results in an upper boundary of 3 hours fuel

remaining, at 1912 GMT.



Considering past AE behaviors, a lack of radio reports after 2013 GMT, and further analysis of an

important instrument in the Electra (the Cambridge Fuel Analyzer), there is a high probability that only

approximately 60 gallons of fuel remained at 1912 GMT – enough for 90 minutes flight time.

A fuel exhaustion time from 2013 GMT to 2100 GMT is highly likely.

This conclusion is well supported by the following analysis, completed after Appendix 1 was published,

involving the Cambridge Fuel Analyzer.

A fundamental question has always plagued investigators and researchers, regarding theories of

excessive fuel consumption on the Lae-‐Howland segment, arrival with far less than planned fuel reserves,

and premature fuel exhaustion prior to landing on Howland Island.

The Cambridge Fuel Analyzer

The answer may very well be found in the Cambridge Fuel Analyzer, or CFA, instrument.

AE’s takeoff fuel quantity at Lae, according to Lockheed, Paul Mantz, Kelly Johnson, Swenson and Culick,

and our own independent analysis, should have enabled the Electra to fly further and longer than it

apparently flew – as much as 3 to 4 hours longer.

If AE was short of fuel, how would it be possible to burn more fuel than planned?

All prior researchers addressing this question concluded that excessive fuel consumption was due to one

of the following

• Incremental en route navigation adding distance to the planned route.

o This would require adding hours of en route time to the original route distance.

• Excessively high and inappropriate operating altitudes for the gross weight of the Electra,

especially early in the mission, requiring excessive engine power and fuel consumption

o Evidence from AE’s 0418 GMT position report at “height 7,000 feet,” the 0519 GMT

position report at “height 10,000 feet,” and the 0718 GMT report at “height 8,000 feet”

indicates that the aircraft is approximately at the optimum altitude prescribed by Kelly

Johnson, and not high enough to produce excessive fuel consumption.

• Excessive headwinds, well above forecasts, caused higher than planned power settings and

resulting fuel consumption

o Evidence exists to validate Long’s headwind value, which was initially more than forecast

on 30 June and 1 July, but within the range of forecasted winds on 2 July.

o 2 July weather forecasts included winds that were expected to be reduced in the second-‐

half of the mission, during the final 8 hours of the flight.

None of these traditional positions explain excessive fuel consumption, are all are considered not valid.



If AE arrived in the Howland area with critically low fuel quantity remaining, i.e., below planned reserves,

there may be a more scientific, and more likely, explanation for excessive fuel consumption. This arises

from understanding the importance of the Cambridge Fuel Analyzer equipment to achieving long range

flight in the Lockheed Electra.

The Cambridge Fuel Analyzer (CFA), sometimes referred to as the Cambridge Exhaust Analyzer, was a

very important tool in the World Flight attempt plan. The CFA monitors exhaust gases, enabling the pilot

to precisely and safely set the optimum mixture control of the fuel-‐air mixture, to ratios that allow

achieving optimum engine performance, minimum fuel consumption, and therefore, maximum aircraft

range. The CFA assures that minimum fuel is consumed, with no adverse effect on engine health.

We showed in Appendix 1 that a fuel burn variance of just 1-‐2 GPH per engine, or 2-‐4 GPH total

additional fuel consumption, could explain a significant fuel remaining variance.

Appendix 1 fuel remaining by our calculation was 123 gallons at 1912 GMT, enough fuel for 3 hours

flight time. If an inoperative Cambridge Fuel Analyzer resulted in AE burning 4 GPH above plan (less than

10% variance) for 15 hours, the aircraft would arrive at 1912 GMT with fuel quantity at just 63 gallons,

approximately 90 minutes fuel remaining.

An airline’s Electra Operating Manual states that without the CFA, the fuel-‐air mixture must be manually

set to a more rich mixture, to prevent engine damage. The resulting higher fuel consumption reduces

aircraft range. In fact, the Electra manual states that maximum chart ranges cannot be achieved without

a functioning Cambridge Fuel Analyzer.

The CFA was used extensively on the Kelly Johnson test flights of AE's aircraft, to maximize engine

efficiency, and obtain the gallons per hour fuel consumption rate for different power settings. Every flight

test data point contained an associated CFA value. These CFA, manifold pressure and propeller RPM

settings were supplied to AE as mission profile specifications, including as detailed cruise specifications

issued by Kelly Johnson for the World Flight.

The Lockheed 487 Report preamble contains the statements

• “To enable close control to be maintained over the mixture strength, a Cambridge gas analyzer

is connected into the exhaust system.”

• “The complete performance has been computed conservatively based on actual flight test

results on Model 10E. Fuel consumption data is based on results that have been obtained in

flight with careful mixture control. To get a range of 4500 miles it will be necessary to calibrate

the Cambridge Analyzer so that the fuel consumption curve shown on page 13 can be obtained.”

• “The Cambridge Gas Analyzers should be carefully calibrated in flight to see if the fuel

consumption data used in this analysis can be obtained.”

o The report L487 was dated June 19, 1936, and subsequently, test flights were conducted

by Kelly Johnson, using the calibrated Cambridge Gas Analyzer, to identify World Flight

performance specifications for AE.



o These recommendations were contained in three telegrams from Kelly Johnson to AE

dated 11 March 1937.18

Clearly, the CFA was very important, and AE adhered to these CFA settings very closely for all flight

profiles.

18 Kelley Johnson, Telegrams for Electra flight test data and World Flight performance recommendations (Western Union 11 March 1937).



Figure 4 -‐ Cambridge Fuel Analyzer



Apparently the CFA was also somewhat fragile, as it was frequently being repaired throughout the World

Flight, at many of AE’s intermediate stops where maintenance was available. The leads to the exhaust

stack, the analysis cells, and calibration were reported as problematic.

• The CFA failed en route to Karachi, and on JUN 16, 1937 AE sent a telegram to George Putnam,

“FUEL ANALYSER OUT ASCERTAIN FROM CAMBRIDGE INSTRUMENT IF POSSIBLE GET

REPLACEMENT OR IF ANYONE AVAILABLE TO REPAIR HESITATE ATTEMPT PACIFIC WITHOUT

[author’s emphasis] CABLE CALCUTTA.”19

o George Putnam replied, “KLM USES CAMBRIDGE CABLING AMSTERDAM

HEADQUARTERS TO ARRANGE CALCUTTA SUPPLY NEW ANALYSIS CELL IF NECESSARY

WHICH BELIEVE FAULTY STOP….”20

During 3 days of maintenance in Bandoeng, JUN 21, 22, and 23, the CFA was again, repaired. Among a

long list of maintenance performed on AE’s Electra, specifically21

• “Two broken leads in left analyzer cell of exhaust analyzer repaired.”

• “Switch on junction box of exhaust analyzer repaired.”

• “Transmitter on left engine of Eclipse flow meter repaired (soldering between pivot and internal

magneto loose) and transmitter adjusted.”

• Alternator of Eclipse flow meter cleaned.

• Oil and fuel filter strainers cleaned.

• Thermocouple No. 3 lead, starboard engine repaired.

• Thermocouple No.2 lead, port engine, replaced.

We know from AE's logs that she then flew from Bandoeng to Surabaya, Indonesia, and the next day,

flew back to Bandoeng for repairs to “an instrument necessary for long range flight.”22

In AE’s own words: “In the air, and afterward, we found that our mechanical troubles had not been

cured. Certain further adjustments of faulty long-‐distance flying instruments were necessary, and so I

had to do one of the most difficult things I had ever done in aviation. Instead of keeping on I turned back

the next day to Bandoeng. With good weather ahead, the Electra herself working perfectly, and pilot and

navigator eager to go, it was especially hard to have to be “sensible.” However, lack of essential

instruments in working order would increase unduly the hazards ahead. At Bandoeng were the

admirable Dutch technicians and equipment, and wisdom directed we should return for their friendly

succor23.”

19 Amelia Earhart, Telegram to George Putnam (Purdue Collection), JUN 16, 1937. 20 George Putnam, Telegram to Amelia Earhart (Purdue Collection), JUN 16, 1937. 21 T. D. Knilm, Bandoeng Inspection Report Lockheed Electra Reg.Markings NR 16020 (Purdue Collection), June 23, 1937. 22 Amelia Earhart, Last Flight, 211. 23 Ibid.



There is likely only one "instrument necessary for long range flight" that AE would not need on shorter

range flights – the Cambridge Fuel Analyzer – and it may be the subject instrument referenced in AE’s

single passage, and in letters written by Fred Noonan.

The Electra also contained Eclipse fuel flow meters, and while occasionally problematic throughout the

World Flight, the fuel flow meters were not necessary, and were never more accurate than the CFA.

This single passage concerning an “instrument necessary for long range flight” was not further

explained, or developed anywhere in the research, and no researchers have addressed this aspect of the

mission.

This may represent a very important finding.

Fred also commented on this seemingly important, instrument. In letters he wrote to Ms. Helen Day, a

friend in Miami, FN alluded to what was likely, the Cambridge Fuel Analyzer24

• 22 June 1937 – from Bandoeng, Java – “We arrived here yesterday from Singapore[,] and as

some minor instrument adjustments were necessary we decided to remain here an additional

day.”

• 27 June 1937 -‐ FN writes again from Koepang, Timor Island, Dutch East Indies after arriving from

Surabaya, Java, in which he references the previous few days, “…we spent considerably more

time in Java than we expected to – had some minor but important instrument adjustments to be

made, and as the Dutch Line is using the new DC3 Douglas – equipped with similar instruments –

we decided to have the work done in their shops at Bandoeng. We remained there from last

Sunday until yesterday – Saturday. Took off once and got as far as Surabaya – about three

hundred and fifty miles – only to have the instruments fail again – so returned to Bandoeng.

They are functioning perfectly now, thank goodness for the Dutch mechanics.”

In a short period of time, this “long range instrument,” which may be the Electra’s CFA, had recently

failed inbound to Bandoeng. It likely failed again after leaving Bandoeng. And even following the return

to Bandoeng, and repairs, the CFA failed just two flight segments later, from Darwin to Lae. It was

serviced in Lae according to servicing records there, which detailed replacement of an analysis cell, which

AE had aboard the Electra.25

The Lae Chief Engineer’s Report26contains entries for repairs to AE’s Electra before embarking on the Lae

to Howland Island segment.

• Oil filters inspected and cleaned – both engines.

• Fuel pump starboard engine removed and replaced.

24 Fred Noonan, Letters to Helen Day (Self published June 1937). 25 J. A. Collopy, Report to Civil Aviation Board (Salamaua: 28 August, 1937). 26 Ibid.



• Thermocouple connection on No. 4 cylinder, starboard engine, repaired.

• New cartridge fitted to exhaust gas analyzer – starboard side

En route to Howland Island, it is quite possible that AE suffered yet another failure of the CFA, which

would adversely affect fuel consumption.

Without the CFA, AE could not set optimum power, or minimum fuel consumption rates, nor attain

maximum aircraft range for the fuel load from Lae to Howland.

At the point of failure, AE may have determined that returning to Lae, or perhaps, Bandoeng, for another

repair of the CFA, was complicated by weather, and unnecessary if careful setting of the engine mixture

was monitored. A return would require an excessive amount of time, perhaps deemed unacceptable to

maintaining the arrival schedule in Hawaii of 4 July 1937.

For whatever reason, AE may have elected to continue without operable Cambridge Fuel Analyzers,

perhaps on one, or both, engines. The result was likely increased fuel consumption, which resulted in

arriving in the Howland area with perhaps half the quantity theoretically possible.

Throughout this research, attempts to acquire documentary evidence of the difference in fuel

consumption between using and not using the Cambridge Fuel Analyzer, were unsuccessful. It is not clear

that such data exists at all, or was ever compiled by the Cambridge Instrument Company,27 Lockheed, or

Pratt-‐Whitney.

Of note is that all of Kelly Johnson’s performance recommendations resulted from use of the CFA. It may

have been so important that AE actually backtracked an entire flying day, and invested another ground

maintenance day, to have this instrument “necessary for long range flight,” repaired.

Sperry Gyro Horizon

One other instrument that may be considered necessary for long-‐range flight could be the Sperry

autopilot system. This equipment relieves the pilot from manually and continuously controlling the

aircraft for many hours. Such relief is beneficial in fatigue management.

The Sperry was repaired in Lae.28

• “Sperry Gyro Horizon (lateral and fore and aft level) removed, cleaned, oiled, and replaced, as

this reported showing machine in right wing low position when actually horizontal.”

The Sperry autopilot equipment was problematic in Miami before commencing the flight to San Juan,

Puerto Rico. Pan Am mechanics identified the problem, which was a faulty initial installation at Burbank,

CA. They corrected the problems and the equipment worked perfectly leaving Miami for San Juan.29

27 Cambridge Instrument Company, LTD, 13 Grosvenor Place, London. 28 J. A. Collopy, Report to Civil Aviation Board (Salamaua: 28 August, 1937).



But this equipment was never identified as problematic throughout the World Flight.

Separate redundant flight attitude instruments of which there were likely two, one for the left seat pilot

and one for the right seat pilot, were necessary for instrument flight in clouds, and at night, during any

flight segment, not specifically for “long range flight,” since the aircraft could be flown manually.

• One artificial horizon instrument was repaired in Bandoeng30 (bar stuck in case).

It is possible that had the Sperry Gyro Horizon autopilot failed, depending at what time that occurred, AE

may have been compelled to return to Lae, and abort the long distance, night, overwater segment to

Howland. Since there were redundant and backup artificial horizon instruments to reference in manually

flying the aircraft, it is doubtful a failure of the autopilot system alone would cause a turn back to Lae.

The most compelling evidence that the Cambridge Fuel Analyzer was the subject of the “instrument

necessary for long range flight” was AE’s investment in having it repaired multiple times, and AE’s

telegram to George Putnam, from Karachi, mentioned above.

As AE stated, “…HESITATE ATTEMPT PACIFIC WITHOUT [Cambridge Fuel Analyzer]…” and this largely

substantiates that the CFA was indeed the necessary instrument, and that had it failed from Lae to

Howland, would certainly have resulted in increased fuel consumption.

Appendix 1 Excerpt – Review and Summary

Combining Pratt-‐Whitney engine data, with Kelly Johnson’s recommendations and data, offers a more

complete profile of fuel consumption.

• Takeoff using 10 gallons

• 1 hour climb using 110 gallons

• 3 hours at 60 GPH using 180 gallons



• 8.5 hours at 38 GPH using 323 gallons

• 0.5 hours descent at 30 GPH (estimated) using 15 gallons

• Total 920 gallons required from takeoff to 1912 GMT

Fuel Consumption and Time Remaining From All Analyses

Below summarizes the solutions for mission fuel consumed, and fuel remaining upon arrival at where AE

thought Howland should be, at 1912 GMT.

29 Elgen Long, Amelia Earhart The Mystery Solved, 130. 30 T. D. Knilm, Bandoeng Inspection Report Lockheed Electra Reg.Markings NR 16020 (Purdue Collection), June 23, 1937.



• If AE began with 1080 gallons, and flew this Kelly Johnson profile (“modified” for takeoff, climb

and descent) requiring 920 gallons, the total fuel remaining would have been 160 gallons at

1912 GMT, or 4 hours endurance.

• Computer flight profile modeling of all available data, but largely from Kelley Johnson and L487

data, also indicate the total fuel remaining would have been 160 gallons at 1912 GMT, or 4

hours endurance.

o While our Jeppesen software model results, in terms of fuel used, corroborate the Kelly

Johnson/L487 Report, our further analysis offers increased accuracy in this area.

• Swenson and Culick’s analysis concluded that AE had enough fuel for 20 hours 38 minutes total

mission time. Subtracting the known mission time of 19 hours 12 minutes, results in

approximately 1 hour 26 minutes remaining endurance.

o This represents 57.3 gallons remaining at 1912 GMT.

• Our research, using a specific flight profile segment analysis technique, results in a total mission

fuel burn of 957 gallons. AE should have arrived at time 1912 GMT with 123 gallons, enough for

3 hours 04 minutes endurance.

Fuel Remaining Implications

Our calculations of 957 gallons fuel consumed result in arriving in the Howland area with 123 gallons.

A failure of the Cambridge Fuel Analyzer would have increased fuel consumption, possibly accounting for

the entire "over burn" of fuel, from the amount that should have produced a sufficiently comfortable

range and endurance upon arrival to the Howland area, to a quantity that may have precipitated the

initial check in at 1912 GMT "we should be on you, gas is running low."

In this case, there would be no gross navigation errors, no large, unexpected headwinds, no

extraordinary climbs to altitudes well in excess of that specified by Kelly Johnson, and no excessive cruise

speeds maintained that would have irresponsibly burned an excessive amount of fuel. Such speeds would

have been statistically abnormal, well outside prescribed ranges and inconsistent with AE’s past

operating performance.

Under a Cambridge Fuel Analyzer failure scenario, the aircraft may have experienced fuel exhaustion

between 2013 GMT and 2100 GMT.



Part III. Detailed Flight Analysis

Validated Statistical Data

Direct evidence includes AE’s flight performance on earlier World Flight segments, in which weather,

winds and navigation challenges were similar to the final flight segment. Terrain was a factor in some

mission segments, however, on the final flight segment, only Bougainville Island presented a terrain

consideration with mountains reaching approximately 8,000 feet.

Wherever first-‐hand factual evidence was available from AE’s flight logs and accounts, that data was

used to establish AE’s historical flight patterns. Analysis of an audit of World Flight mission segments

provides important understanding for mission performance.

This data is also important when considering alternative flight profiles and mission outcomes, offered by

various authors. When alleged mission flight parameters fall outside an established pattern of historical

performance, the associated theory and conclusions demand careful scrutiny. The business analogy is

that if a performance factor were well outside statistical Quality Assurance ranges, such as Six-‐Sigma, or

Control Chart limits, it would exist as an abnormal data point, one requiring additional validation.

Some alternative theories about the World Flight, for example, require aircraft and mission performance

that exceeds capabilities or that falls well outside historical patterns.

Winds

There are 7 weather reports relevant to this mission segment.

Reported wind speeds from weather observations are in mph. Only AE’s position report of wind speed

was in knots at 0718 GMT.

Two reports are from Hawaii Headquarters, one issued 1 July and handed to AE, and one issued 2 July

and broadcast from Lae to AE.31

Both ship-‐based and shore-‐based weather reports of upper winds are not extremely accurate in 1937. A

meteorograph instrument was sent aloft under a tethered balloon or kite, where it recorded a few

parameters for examination following retrieval. Upper winds may also have been established from an

observation made by a qualified weather person.

31 ComHawSec Fleet Base Pearl Harbor messages, (Hawaii: Headquarters, 1-‐2 July, 1937).



Two reports are from Itasca, both at noon local time. One, on June 30, 1937 reported winds at 5000 feet

from the east (090 deg) at 22 mph. The other, on July 1, 1937 reported winds at 7000 feet ENE (060 deg)

at 30 mph and at 9000 feet ENE (060 deg) at 31 mph.32

One report is from AE at 0718 GMT (1718 local time) on July 2, 1937, as an in-‐flight position report, in

which a reference to “winds 23 knots” is made. No direction was specified.33

One report is from the USS Ontario, July 2, 1937 bridge logs, that reported surface wind ENE (060

degrees) at force 3-‐4 (up to 16 knots) but it is only a surface report of sea state and winds.34

One report is from Nauru Island, on July 2, 1937 at 0800 local time GMT, approximately 3 hours prior to

AE’s departure from Lae, and nearly 10-‐12 hours prior to AE’s arrival in the vicinity of Nauru Island, en

route to Howland. In this report, upper wind values were reported at 4000 feet from 090 deg at 12 mph

and at 7500 feet from 090 deg at 24 mph.35

This is evidence that at the mid-‐point of the Lae to Howland Island segment, upper winds were very close

to those used by Long (26.5 mph) and our own baseline analysis.

Long36 assumed a constant headwind of 26.5 mph (23 knots) throughout his analysis. In arriving at this

value, Long likely considered the AE in-‐flight position report at 0718 GMT reported wind value, and a

single Nauru Island weather observation with wind direction and values linearly extrapolated to assess

winds at AE mission altitudes of 8,000 and 10,000 feet.

While wind profiles are often not linear, over small altitude differences, a linear interpolation is

sufficiently accurate for this analysis. Evidence exists that wind velocity was reduced, and direction

shifted slightly, in the second-‐half of the mission.

For this research, the authors used upper winds from 070 deg magnetic at 23 knots, or 26.5 mph. On

course to Howland Island, this was a headwind component of 23 knots, or 26.5 mph. Sensitivity analyses

for second-‐half wind changes were completed, with resulting aircraft positions contained in the search

grid.

Speeds – Aircraft and AE Performance

There are seven principal sources of historical and statistical in-‐flight performance data. These include

L487; Kelly Johnson Telegrams; Electra capabilities in terms of power, speed, and fuel consumption, from

operating manuals and Pratt-‐Whitney engine data; AE’s first-‐hand reports during her World Flight

32 Itasca, Message logs. 33 Eric Chater, Letter to Mr. M. E. Griffin, 8. 34 Randall S. Jacobson, Ph.D., The Final Flight – Part 2, (TIGHAR.org). 35 Laurence Safford, Amelia’s Flight Into Yesterday, 195. 36 Elgen Long, Amelia Earhart – The Mystery Solved, 18.



performance37; research by Long; and research by Swenson and Culick38 with aerodynamic and engine

performance research.

Definition of speed is important in understanding a Lae-‐Howland specific segment analysis.

Below is a table compiled from two reference sources, Long39 and Finch.40 The data was crosschecked

with notes reported by AE41, providing a single source for historic mission segment examination.

The data show that in 30 World Flight legs, excluding 3 test flights of short duration (less than 2.5 hours)

the average ground speed is 142.1 mph.

This is useful in assessing various AE reported speeds, that often omitted units (statute or nautical miles

per hour), or what type of speed was being used (indicated, true or ground speed). AE frequently omitted

other details, such as altitude, outside air temperature, and winds, from her in-‐flight reports.

Statistical data combined with report times and positions, helps to assess the reasonableness of aircraft

performance and to corroborate other data.

A report of speed in knots likely resulted from FN calculations, handed to AE for reporting, since FN likely

worked in nautical miles from navigation charts, and AE’s airspeed indicator was calibrated in statute

miles per hour. AE, simply due to the state of aviation in 1937, most likely did not possess the tools to

convert statute miles per hour to knots, or to work between indicated, true, and ground speed, from the

cockpit and without reference to published tables or graphs.

AE’s Lae to Howland performance is defined from corroborating power settings, Brake Horsepower,

Cambridge Fuel Analyzer indications, L487 and Kelly Johnson recommendations, and statistically

validated to calculated and historical values. These values can be used to determine flight path data,

with reasonable assurance that a re-‐calculated flight path represents an accurate calculation.

37 Amelia Earhart, Last Flight. 38 F. E. C. Culick, Analysis of Amelia Earhart’s Final Flight (Consulting Report). 39 Elgen Long, Amelia Earhart – The Mystery Solved, 250. 40 Linda Finch, No Limits, (San Antonio: World Flight, Inc., 1996) 113. 41 Amelia Earhart, Last Flight.



Table 1 – Segment Speed Performance

FROM TO DATE TIME DIST NM FLIGHT

TIME AVG GS KTS AVG GS

MPH

OAKLAND BURBANK 20-May-37 1550 283 2.25 125.78 144.75

BURBANK TUCSAN 21-May-37 1425 393 3.33 118.02 135.82

TUCSON NEW ORLEANS 22-May-37 730 1070 8.67 123.41 142.02

NEW ORLEANS MIAMI 23-May-37 910 586 5 117.20 134.87

MIAMI SAN JUAN 1-Jun-37 556 908 7.56 120.11 138.22

SAN JUAN CARIPITO 2-Jun-37 650 492 4.53 108.61 124.99

CARIPITO PARAMARIBO 3-Jun-37 848 610 4.83 126.29 145.34

PARAMARIBO FORTALEZA 4-Jun-37 710 1142 9.33 122.40 140.86

FORTALEZA NATAL 6-Jun-37 650 235 2.08 112.98 130.02

NATAL SAINT-LOUIS 7-Jun-37 313 1727 13.37 129.17 148.65

SAINT-LOUIS DAKAR 8-Jun-37 905 100 0.87 114.94 132.28

DAKAR GAO 10-Jun-37 651 1016 7.92 128.28 147.63

GAO FORT LAMY 11-Jun-37 610 910 6.63 137.25 157.95

FORT LAMY EL FASHER 12-Jun-37 1224 610 4.1 148.78 171.22

EL FASHER KHARTOUM 13-Jun-27 610 437 3.25 134.46 154.74

KHARTOUM MASSAWA 13-Jun-27 1050 400 2.83 141.34 162.66

MASSAWA ASSAB 14-Jun-37 730 241 2.43 99.18 114.13

ASSAB KARACHI 15-Jun-37 313 1627 13.37 121.69 140.04

KARACHI CALCUTTA 17-Jun-37 725 1178 8.33 141.42 162.74

CALCUTTA AKYAB 18-Jun-37 705 291 2.45 118.78 136.69

AKYAB RANGOON 19-Jun-37 842 268 2.5 107.20 123.37

RANGOON BANGKOK 20-Jun-37 630 315 2.72 115.81 133.27

BANGKOK SINGAPORE 20-Jun-37 1027 780 6.47 120.56 138.74

SINGAPORE BANDOENG 21-Jun-37 617 541 4.33 124.94 143.78

BANDOENG SURABYA 24-Jun-37 1400 310 2.58 120.16 138.27

SURABAYA BANDOENG 25-Jun-37 600 310 2.5 124.00 142.70

BANDOENG SURABAYA 26-Jun-37 1154 310 2.6 119.23 137.21

SURABAYA KOEPANG 27-Jun-37 630 668 5.5 121.45 139.77

KOEPANG DARWIN 28-Jun-37 630 445 3.43 129.74 149.30

DARWIN LAE 29-Jun-37 649 1012 7.72 131.09 150.86

AVG 119.49 142.10

SDEV 12.14

This graph below of average speeds flown on each World Flight mission segment, illustrates two

important conclusions.

• AE typically operated at parameters specified by experts, especially for longer duration flights.

• AE’s performance consistently adheres to a reasonably small range of speeds.



The data shows a larger variance in speed for shorter segment lengths. As the segment length increases,

the speed variance decreases, approaching speeds recommended by the L487 Report42 and Kelly

Johnson.43

This process increases confidence in the preflight planning, flight parameter specifications, and, for the

few longer segments flown by AE, a sense that these values were typical.

The final mission segment is not included in this data, since a definite completion time was not

established.

Figure 5 – Average World Flight Ground Speed

42 Clarence L. “Kelly” Johnson and W.C. Nelson, Lockheed Report 487 Range Study of Lockheed Electra Bimotor Airplane (California, Lockheed Aircraft Company -‐ June 1936). 43 Kelley Johnson, Telegrams -‐ Electra flight test data and World Flight performance recommendations (Western Union 11 March 1937).



This graph below depicts flight segment times, providing an interesting perspective of some of the

human factors involved in this flight.

The 30 World Flight times in the graph average 5.1 hours per flight segment. For comparison, the Lae to

Howland segment was planned for approximately 18 hours, and lasted in excess of 20 hours.

• The maximum flight time prior to Lae, was 13.37 hours, recorded for two mission segments.

o No other mission segment was more than 10 hours.

• AE had completed flights of durations approaching the length of the Lae-‐Howland segment.

o On May 20-‐21, 1932, AE completed a solo transatlantic crossing in 14 hours 56 minutes.

o On August 24-‐25, 1932 AE completed a solo non-‐stop transcontinental crossing in 19

hours 5 minutes.

o On July 7-‐8, 1933, AE completed a transcontinental crossing in 17 hours 7 min.

o On January 11, 1935 AE completed a solo flight from Honolulu to Oakland in 18 hours.

o On May 8, 1935, AE completed a Mexico City to Newark flight in 14 hours 19 minutes.

AE was no stranger to long flights, yet all were completed 2-‐5 years earlier, none were to islands, and

none required a need for maximum range performance and fuel management to the level required from

Lae to Howland Island.

This data provides insight into not only the challenge undertaken by AE and FN, but the complexity of this

operation relative to their previous experience.



Figure 6 – Average Segment Length

Flight Modeling – Lae to Howland Island

For this research, prior to AE’s 0718 GMT in-‐flight position report, climb speeds were determined from

L487 and Kelly Johnson power setting recommendations, engine operating limitations, climb speed

specifications, with consideration of climb rate as reported by Pellegreno.

From AE’s 0718 GMT in-‐flight position report, to Howland Island, the re-‐calculated true airspeed was

determined by setting power in accordance with L48744 and Kelly Johnson recommendations,45 with

reference to direct evidence from previous flight profiles, statistical reference, and behavior where AE

included specifics about power setting and speed, in flight notes. Lockheed and Pratt-‐Whitney data were

also considered.

This technique produced en route speeds after 0718 GMT, of 138 knots true air speed, or 158.8 mph.

44 Clarence L. “Kelly” Johnson and W.C. Nelson, Lockheed Report 487 Range Study of Lockheed Electra. 45 Kelley Johnson, Telegrams -‐ Electra flight test data and World Flight performance recommendations.



Applying the 23 knots, or 26.5 mph, headwind component, produced 116 knots ground speed, or 132.3

mph ground speed, after the 0718 GMT position, which was held until the perceived descent point to

Howland Island at approximately 80 statute miles per Kelly Johnson, Paul Mantz (OAK-‐HNL) and Fred

Noonan recommendations.

Our result of 132.3 mph ground speed, from the 0718 GMT position to Howland Island, is only 1.7 mph

(1.2%) less than Long’s overall mission average ground speed. Our result of 158.8 mph true air speed is

also 1.7 mph (1.1%) less than Long’s overall average true air speed.

These are considered valid performance numbers, and when combined in a discrete and stepwise

analysis, the modeling technique provides a more accurate profile.

• Despite flying a Lockheed Model 10A aircraft with smaller engines, less weight and likely a lower

drag profile, Pellegreno46 routinely observed ground speeds of 133-‐135 mph during a

Commemoration Flight, indicating that computed speeds are in the range of reasonable

performance.

• Pellegreno’s aircraft has effectively the same horsepower-‐to-‐weight ratio as AE’s Electra 10E.

• Long assumed a constant overall true air speed of 160.547mph, in the presence of a constant

headwind component of 26.5 mph, producing an overall mission average ground speed of 134

mph.

• Long’s approach of averaging distance and time was updated in our research using a discrete

approach, a stepwise analysis at each waypoint, facilitated by software.

Using flight planning and analysis software to model the climb, cruise, descent performance and wind

effects, can produce a more accurate overall mission analysis. The software enabled modeling three

flight paths, sensitivity analyses from headwind speed and direction modifications, and examination of

route timing and the terminal EON position.

Further corroboration of these results is found in L48748 that recommended flying at 155 mph indicated

air speed at 2,000 feet, 145 mph indicated air speed at 4,000 feet, and 135 mph indicated air speed at

8,000 feet. This profile was apparently not flown, as it was pre-‐empted by later Kelly Johnson profile

recommendations, which appear to have been executed and adhered to on many World Flight segments,

including the Lae to Howland Island segment. The 8,000 feet speed specification is very near what AE

likely flew.

The later Kelly Johnson recommendations specified flying at 8,000 feet, and under conditions that likely

existed during AE’s flight, are equivalent to 155.4 mph true air speed. Kelly Johnson Telegrams49

46 Ann Pellegreno, World Flight – The Earhart Trail (Ames, Iowa: Iowa State University Press, 1971) 60, 177. 47 Elgen Long, Amelia Earhart – The Mystery Solved, 194. 48 Ibid. 7 49 Kelley Johnson, Telegrams -‐ Electra flight test data and World Flight performance recommendations.



indicated power settings and speeds, showing that after 0718 GMT, a target speed would be 133-‐158

mph true air speed.

• This data and resultant recommendations were based on analytic aerodynamic calculations

including wind tunnel testing, and actual flight test data from AE’s aircraft.

L48750 provided values for flight at sea level, with no altitude adjustments, and recommended flying 150

mph true air speed in still air, and with a 20 mph headwind, flying 154 mph true air speed.

Table 2, from 0718 GMT to approximately 1830 GMT, compares cruise performance in statute miles per

hour (MPH), for this specific cruise segment.

Table 2 – Comparative Speed Calculations

Performance Parameter Our Flight Plan Long Research51 L487 Recommendations Indicated Air Speed 138.1 139.2 135.0 True Air Speed 158.8 160.5 155.4 Ground Speed 132.3 134.0 132.4

AE adhered remarkably close to these recommendations. These speeds are highly corroborated.

The MSI and modeling process forms a corroborating body of evidence of the likely mission flight

performance actually achieved on the Lae to Howland Island mission segment, in terms of speed, fuel

consumption, position and time. MSI incorporated a broader range of corroborated data sources:

• All AE in-‐flight reports

• AE historical performance data

• The Nauru Island weather observation of upper altitude winds

• Data used by Long

• The L487 report aerodynamic data

• Kelly Johnson recommendations

• Swenson and Culick’s analysis

• Our independent analysis for validation of previous work

• Lockheed Electra Operating Manuals

• Pratt-‐Whitney engine operating data specific to AE’s engines

50 Clarence L. “Kelly” Johnson and W.C. Nelson, Lockheed Report 487 Range Study of Lockheed Electra. 8 51 Long used overall averages for analysis.



Using this MSI blending process we calculate performance used in our aircraft modeling and flight

planning process, as follows:

• Indicated Air Speed within 2.3% of L487 and 0.8% of Long

• True Air Speed within 2.2% of L487 and 1.1% of Long

• Ground Speed within 1.2% of L487 and 1.3% of Long

This methodology directly affects speed, time, fuel consumption, and most important, final position.

Except for lateral navigation track errors or deviations from a planned path, speed and fuel consumption

are the most fundamental parameters in locating the Electra, and worthy of close scrutiny.

Improved Accuracy

Modern methods yielding 2% improvements in a solution represent approximately 50nm in a final EON

point on a Lae to Howland Island segment.

Performance Specification Challenges

Among sources of Lockheed Electra 10E aircraft performance specifications, Lockheed and Kelly Johnson

provide reference data. Lockheed Electra Operating Manuals provide good information. AE provides data

in nine citations of some aspect of en route aircraft performance.52 Pellegreno provides two climb

airspeed citations and two en route ground speed citations under normal wind and weather conditions

that are useful.53

Lockheed Report 487 54 contains extensive aerodynamic and performance analyses of the Lockheed

Electra Model 10E.

Completed 13 months in advance of the actual World Flight attempt, this report detailed a

recommended flight profile, flight parameter recommendations, and supporting aerodynamic data.

Among these, are useful information on engine power settings for Brake Horsepower (BHP), Manifold

Pressure (MP), propeller RPM (RPM), fuel flow in gallons per hour (GPH), flight speed, range, fuel

consumption, and Cambridge Fuel Analyzer settings.

Conversion factors used in this analysis55 are shown below.

• 1 nautical mile per hour = 1.1508 statute miles per hour

• 1 nautical mile = 1852 meters = 1.1508 statute miles = 6076.1 feet.

52 Amelia Earhart, Last Flight. 53 Ann Pellegreno, World Flight – The Earhart Trail. 54 Clarence L. “Kelly” Johnson and W.C. Nelson, Lockheed Report 487 Range Study of Lockheed Electra. 55 AIAA Aerospace Design Engineering Guide, AIAA, September 2003.



These conversions are important. Charts, tables, AE in-‐flight position reports of speed and distance, Fred

Noonan’s notes to AE and radio logs of communications, contain either no definitions for the metrics

being reported, or when a unit of measure is defined, it sometimes conflicts with other reports, historical

accounts, or engineering data.

Within L487,56 and in most every resource, flight speed is frequently not defined in terms of the units,

nautical miles per hour (knots) or statute miles per hour (MPH). In some cases in the same report, speed

units are mixed in different charts or tabular data, and flight speed is sometimes defined in one graph,

and not defined in other graphs or tables.

In every case, these precise units of measure require definition to enable meaningful analysis.

This complicates all analyses.

Flight speed is an important metric. There are three flight speed measures of interest, and in this

research the authors have been required to calculate, and identify the measure being used in a majority

of historical references.

• AE’s airspeed indicator was calibrated in statute miles per hour, or MPH. AE flew her airplane

with reference to MPH. This is Indicated Air Speed (IAS) in MPH.

• When Indicated Air Speed in MPH is corrected for altitude (pressure and temperature) the result

is an associated True Air Speed (TAS) in MPH. This is “over the earth” speed in a no wind

condition.

• When TAS in MPH is corrected for headwinds and tailwinds, the result is Ground Speed. This is

the aircraft’s actual speed over the ground, in the air mass existing at the time of flight.

• For distances measured in nautical miles, the associated speeds are defined as knots, or nautical

miles per hour.

While AE’s IAS registered in MPH, many charts such as aeronautical and marine charts are presented in

nautical miles. Fred Noonan’s chart navigation was likely in nautical miles, requiring a conversion from

nautical miles (or NM per hour which is defined as Knots) to statute miles (or statute MPH).

“Speed 140 knots…”

As an example of this complexity and the importance of precise specifications, AE provides, according to

Chater, an in-‐flight position report at 0418 GMT including a report of “140 knots.”

• Chater57 reports this as 140 knots.

• Collopy58 reports this as 150 knots.

56 Clarence L. “Kelly” Johnson and W.C. Nelson, Lockheed Report 487 Range Study of Lockheed Electra. 57 Eric Chater, Letter to Mr. M. E. Griffin 58 J. A. Collopy, Report to Civil Aviation Board (Salamaua: 28 August, 1937).



The type of speed is not specified. It could be 140 knots True Airspeed, Indicated Airspeed, or Ground

Speed. The implications of each are very important.

Referring to L487,59 for ambient meteorological conditions likely at 0418, area weather reports indicate

outside air temperature at sea level of approximately 83 degrees F. Using the standard adiabatic

temperature lapse rate of -‐3.5 degrees F per 1000 fee to find the ambient temperature at AE’s cruise

altitude, we find that if “140 knots” were an indicated air speed, it would imply the aircraft was flying at

a true air speed beyond the Electra’s performance capability at its gross weight at 0418 GMT.

Similarly, if “140 knots” were a ground speed, with an assumed 23-‐knot headwind component (26.5 mph

headwind defined by Long), the true airspeed required is again, beyond the Electra’s performance

capability at its gross weight at 0418 GMT.

If “140 knots” were a true air speed (equivalent to 161.1 mph true air speed), it would place AE’s

indicated airspeed in miles per hour (143 mph IAS), in the range of historical performance and Electra

capabilities, and near the speeds prescribed in L487 and Kelly Johnson,60 and Paul Mantz

recommendations.

If the reported speed was 150 knots, and a true air speed, this would be uncharacteristically high for the

Electra’s gross weight and mission time, atypical of AE’s performance, and beyond statistical norms.

At 140 knot, and 161.1 mph true air speed with the assumed 26.5 mph headwind (Long), AE’s ground

speed would have been 134.6 mph, which is within 7 mph (5.6%) of AE’s statistical range of historical

World Flight performance, within the Electra’s capabilities at that gross weight, closely aligned with

flight recommendations, and typical for the mission time en route.

The conclusion is that AE’s report of “140 knots” is a true air speed. Fred Noonan likely handed AE the

data to make this report (in knots), and AE was flying very close to recommended or prescribed

parameters. This precise and consistent performance is typical for AE throughout the World Flight, and

vitally important to understanding the Lae to Howland Island mission segment.

Further, Chater’s report61 is considered more accurate regarding this reference to speed.

Fred likely worked in knots and nautical miles, making conversions from AE’s indicated airspeed and

meteorological data such as outside air temperature. There would be no instrument indication

presenting “knots” to AE in the cockpit, and AE would likely not have made conversions from mph to

knots with Fred aboard, and possibly, not at all. The charts and process for these calculations were

largely unavailable for most flying in 1937. The conversions were not easily performed, and no handy

calculators existed to make the job easier or more reliable.

59 Clarence L. “Kelly” Johnson and W.C. Nelson, Lockheed Report 487 Range Study of Lockheed Electra. 60 Ibid. 61 Ibid.



In 1937 aviation, flying was referenced to “miles per hour,” which is statute miles per hour.

The ubiquitous handheld calculator, the E-‐6B flight computer, made it possible for pilots to easily and

rapidly compute speeds, winds, conversions, and other flight performance data. Unfortunately, it was

effectively not yet invented in July 1937, and did not gain widespread use until mid-‐WWII.

Flight Data - AE Natal to Dakar

This flight segment was the longest over-‐water portion of the World Flight, and among the two segments

with the longest duration, prior to the planned Lae-‐Howland segment. AE crossed the Atlantic at night,

just as the planned Lae to Howland flight would be executed.

Position and Time

In AE’s flight notes62, this flight segment offers the most comprehensive detail of flight conditions,

speeds, outside air temperature, aircraft location (by calculation), possible sun position, and factual data

of any World Flight segment. It’s worth studying carefully, and it relates directly to the Lae to Howland

segment.

• These notes are recorded in a logbook fashion, at “6:50.”63

o Takeoff from Natal was at “…0315 in the morning...”

• We assessed this as local time.

• The notation “6:50” could be the mission elapsed time since takeoff.

• The notes include “crossing the equator” which was approximately 513sm from Natal, and would

have corresponded to approximately 3 hours 30 minutes flying time, crossing the equator at

approximately 0645 AM local Natal time.

o “6:50” is then the Natal local time of this logbook entry, and the local time of the

equator crossing.

o With this entry is “sun brilliant” which may refer to sunrise, which in Natal on the

morning of June 7, 1937 was at 0636 local time.

• Later in these same notes, AE records an entry titled “9:41 Natal time.” In this entry AE notes 147

mph for 8 hours [since takeoff] covering 1176 statute miles.

o This 147 mph is a ground speed, multiplied by time and resulting in a distance covered.

o “9:41 Natal time” is 6 hours 26 minutes elapsed mission time, approximately the mid-‐

point of the Atlantic crossing. Natal to Dakar is a 3-‐hour time zone change. AE notes

their time airborne as 8 hours since takeoff. This may simply be an error, or the entry

“9:41 Natal time” could simply be unrelated to the notes about speed, time and distance.

62 Amelia Earhart, Last Flight. 63 ibid. 131.



At “9:41” Natal time, on June 7, 1937, the sun azimuth from true north was 050.35 degrees, and its

elevation above the horizon was +40.81 degrees. AE writes that “…they can hardly believe the sun is

north of them.…” Their true course to Dakar was approximately 038 degrees. The sun would have been

slightly to the right of their heading, south of their course, if they were on course. If they were heading in

a more easterly direction, the sun would indeed appear north of them.

From AE’s logs we know that AE was north of course at some point in the crossing. It is possible that

these observations of the “…sun…north of them…” were made after a heading correction to rejoin their

original track to Dakar. This heading correction would place the sun to their left, possibly appearing as if

it was “north” of them.

These observations are tremendous insights into flight parameters, mission timing, how AE recorded

information, and the accuracy of their navigation.

All of these are central to the Lae-‐Howland recalculation.

En route Weather – Overcast or Undercast

In AE’s notes from Natal to Dakar,64 at approximately the halfway point, she writes, “High overcast now.

Good visibility except now and then showers. Fred takes sight. Says we’re north of course a little.”

The importance of this entry is significant for the Lae-‐Howland segment. The insight here is that with a

high overcast, Fred could not take a sight, unless the “overcast” was actually an “undercast.”

Even today, pilots observing a cloud deck below them in cruise flight sometimes refer to the condition as

an overcast sky. The term “undercast” is not widely used, or common in the “pilot-‐vernacular” of aviation

today, and in 1937 aviation, it likely wasn’t yet conceived.

In several AE Lae to Howland in-‐flight position reports, references to “overcast” conditions are made.

• At 1415 GMT, AE reported “cloudy and overcast.”

• At 1515 GMT, AE reported “overcast.”

• At 1627 GMT AE reported “partly cloudy.”

Traditionally, researchers have concluded, in reference to these reports, that the sky above AE was

indeed as reported, “overcast.” However, it is possible that we have misinterpreted flight conditions,

from semantic or contextual differences between today, and 1937.

If AE was in fact reporting an “undercast,” which we believe is likely, it means that FN had good celestial

navigation targets (as AE stated), could take good position fixes, and assure that they were on their

planned track from Lae to Howland.

64 Amelia Earhart, Last Flight.



This conclusion has a significant effect on the end-‐of-‐navigation position. It essentially allows that AE had

a good opportunity to be on course to the end-‐of-‐navigation fix. It could further allow that AE descended

at the perceived descent point, slightly early, and while on track.

The end-‐of-‐navigation fix would then be quite accurate.

The Lae to Howland implications from studying these World Flight segments preclude wildly off-‐track

navigation positions, gross timing and navigation errors, poor en route weather conditions, or excessive

fuel use due to large un-‐forecast headwinds, or in greatly varying distances flown on various profiles

proposed in some previous works.

This understanding increases confidence in the end-‐of-‐navigation and fuel consumption calculations.

Aircraft Fuel Load

AE writes of refueling the aircraft at Natal, and with some concern for adequate fuel quantity, for using

the “secondary” grass runway at Natal, and for departing that runway, “…in the dark with such a heavy

load….”

She had a backup plan, as she frequently detailed throughout her flying experiences, which called for

delaying that takeoff until more suitable conditions existed. Her backup plans for fuel generally included

a safety margin.

AE and FN examined that grass runway by walking its length with flashlights, and ultimately departed as

planned, “…we got into the air easily.” This is the 1937 equivalent of today’s safety risk management

process.

In Natal, the Electra was likely refueled to approximately 80% of the fuel loaded at Lae. The Natal-‐Dakar

segment of approximately 1900 statute miles was 656 statute miles less than the planned distance from

Lae-‐Howland, or approximately 74% of the Lae-‐Howland distance At AE’s baseline 150 mph still-‐air

ground speed, the 4.4 hour difference in mission time, at nominally 50 gallons per hour, would mean 218

less gallons of fuel were required at Natal, and a takeoff fuel load from Natal was approximately 862

gallons. This provided more than 4 hours endurance at destination.

AE stated on the OAK-‐HNL flight segment that she considered 4 hours reserve fuel an adequate safety

margin, “Incidentally, we arrived at Hawaii with more than four hours’[sic] supply of gasoline remaining,

which would have given us over 600 miles of additional flying, a satisfactory safety margin.”65

It is important to note in that passage, that AE’s baseline speed is 150 mph ground speed as

recommended, and apparently 50 GPH as a general fuel consumption rate.

Here, Natal to Dakar, we have the second incidence of knowing that AE planned for a 4-‐hour fuel reserve.

65 Amelia Earhart, Last Flight, 63.



This has implications for the Lae to Howland segment, in terms of how much fuel AE planned upon

arrival at Howland Island. While perhaps not 4 hours, AE may have planned at least 3 hours fuel

remaining at Howland Island, 120-‐150 gallons of fuel, again providing us with a valuable insight to what

went wrong on the Lae to Howland segment.

AE’s details of the Natal to Dakar flight parameters after 6 hours 50 minutes can be compared with her

in-‐flight position reports from Lae, made at 0718 GMT, as a quality assurance process.

In-Flight Speed and Performance

Following, the two segments, Natal-‐Dakar (St. Louis) and Lae-‐Howland, are compared and evaluated.

AE writes at 6:50 elapsed mission time:

• Indicated Air Speed 140 (likely in mph since her airspeed indicator was calibrated in mph)

• Altitude 5,780 feet

• Manifold pressure 26.5 inches

• RPM 1700

• Outside Air Temperature 60 (likely indicated air temperature in degrees Fahrenheit)

These conditions equate to approximately a power setting of 250 Brake Horsepower (BHP), burning

approximately 46-‐49 gallons per hour in cruise flight. Accounting for an estimated 70 gallons for climb in

the first hour, 25 gallons for a 30-‐minute descent, and a cruise portion of 11.8 hours at an average 47.5

gallons per hour, the Natal-‐St. Louis segment should have consumed 655 gallons. From an initial fuel

load of 862 gallons, at least 4 hours fuel remained at arrival in Dakar (St. Louis).

AE likely adhered as much as possible to these parameters during the Lae-‐Howland segment.

Comparing Natal-Dakar (St. Louis) and Lae-Howland

We can make some comparative assessments. For example, if we use the same Natal-‐Dakar climb and

descent numbers for fuel and time, it leaves a Lae-‐Howland 17.7-‐hour cruise segment at 47.5 gallons per

hour, consuming 841 gallons. Adding the climb and descent, the Lae-‐Howland mission fuel consumption

would have been 936 gallons.

Our Lae to Howland specific fuel consumption analysis resulted in a segment fuel consumption of 957

gallons, leaving 123 gallons of fuel remaining at Howland.

We have two different mission segments, two very different computational methods and processes, one

generalized and one very specific, and two conclusions for segment fuel consumption, that differ by just

2.2%. The confidence in these solutions, the Lae to Howland analysis, the End-‐of-‐Navigation point, and

the possible location of the Electra, increases with each MSI corroboration.

Reproducing Table 1 and including data from AE’s Natal-‐St. Louis flight segment provides analytical

corroboration, and again reflects AE’s consistent, disciplined adherence to specified flight parameters.



Table 3 – Table 1 with added detail for Natal to Dakar mission segment.

Performance Parameter

Our Flight Plan Long Research L487 Recommendations

AE Flight Notes Natal-‐St. Louis

Indicated Air Speed 138.1 139.2 135.0 140.0 True Air Speed 158.8 160.5 155.4 154.2 Ground Speed 132.3 134.0 132.4 134.266

Part IV. Detailed Flight Path Navigation and Position Reporting

Howland Island Coordinates

We discovered eight different coordinates in use by various authors, organizations, ships, and charts.

Our navigation analyses used the charted coordinates for Howland Island in 1937, from Clarence

Williams, on AE’s flight planning paperwork.

• N 0 deg 49 min / W 176 deg 43 min

Elgen Long used [N 0 deg 49 min / W 176 deg 38 min].

Author Captain Riley, in a piece discussing the varying coordinates for Howland Island, reported the 1937

position as [N 0 deg 53 min / W 176 deg 35 min] and the more current position at the time of his writing

as [N 0 deg 48 min / W 176 deg 38 min].

Commanding Officers of USS Colorado, USS Lexington, and 1st LT Daniel Cooper of the Army Air Corps

aboard Itasca, all included positions for Howland Island in their final reports for this accident. Only 1st LT

Cooper used the same coordinates as Clarence Williams, and likely AE as well. Each of the two Navy ships

used different coordinates for Howland Island, and neither matched Williams’ and Cooper’s coordinates.

The U.S. Naval Observatory cites Howland Island coordinates as [N 0 deg 54 min / W 176 deg 36 min].

Google Earth shows the Howland Island coordinates as [N 0 deg 48 min 28 sec / W 176 deg 37 min].

These are based on the WGS84 geodetic datum.

A plot of Howland Island from Chart 617 4617 shows [N 0 deg 49 min / W 176 deg 40 min].

The entries here are for completeness – all of the variances in island position are within a small range.

The most important factor is that AE’s position for Howland Island was approximately 6nm west of the

actual island.

66 AE estimated 20 mph headwind for the first half of this Natal-‐St. Louis flight segment.



For an arrival short of Howland, this only adds to the challenge of visual acquisition. Geodetic Datums

This area was examined for its impact on the mission. While many geodetic datums are presently used

around the world, the differences among them are not large in most cases, in terms of locating object

coordinates within a few hundred feet of actual locations. Other charting and location differences can

produce more significant variance, such as occurred at Howland Island.

The difference between the 1937 Howland Island position, and today’s WGS84 coordinates for Howland

Island, is 5.92 nautical miles, 6.82 statute miles, on a bearing from the 1937 position of 095.17 degrees

true.

The actual location of Howland Island, east of its charted position in 1937, was not a trivial threat to

success. Had the flight from Lae to Howland been executed perfectly in all respects, AE would have been

nearly 7 statute miles and, at maximum endurance speed, approximately 3.5 minutes flying time, west of

the actual land mass of Howland Island. Visual acquisition of Howland Island from 10 miles is known to

be difficult – the island could be missed.

This was a significant handicap, given the difficulty of visually locating the very small island.

Specific Flight Path Navigation Summary – Lae to Howland Island

We have confidently specified the aircraft’s performance in terms of speeds, power settings, fuel

consumption, and time.

With these important mission flight parameters accurately specified, and using reasonable assumptions

for the value of winds aloft, we have a good assessment of along-‐track navigation.

Following is an examination of lateral navigation issues.

Lateral Navigation – Lae to Howland Island

Flight Paths A, B, and C, were analyzed with other data previously described, additional AE in-‐flight

position reports, Itasca radio logs, and Nauru Island radio logs, etc.

Flight Path A is a great circle direct routing from Lae to Howland Island. As mentioned earlier, this is not

a likely path as it penetrates forecast areas of dangerous convective weather, and passes over large land

masses where convective weather is most likely to exist.

Flight Path B is modified from Path A to pass through the incorrectly reported, or stated, 0519 GMT

position, known to be incorrect in terms of longitude, or time. Path B must be considered for two reasons

• The path shows a southerly deviation around forecast weather.

• On the Electra’s flight progress, it passes this reported coordinate at 0218 GMT. It is possible

that the coordinate is correctly recorded, yet the time was incorrectly noted as 0519 GMT



instead of 0218 GMT. The numeral “5” could have actually been reported by AE as a “2,” and

transcribed in error.

Flight Path C is an alternative flight path with consideration that the 0519 GMT report of longitude was

either incorrectly reported by AE, or incorrectly stated by Chater.67 Path C is created with consideration

that the recounted longitude value of W 150.7 may actually have been W 157.0.

Using this new position, several results emerge, notably that flight path modeling in speed and time

results in all reported positions in agreement within approximately 5% of the in-‐flight position report

times.

This is more precise than the reporting exhibited on the first Oakland to Honolulu segment, but, as the

most critical segment of the flight, AE and FN may have worked hard to be more precise on the Lae to

Howland segment.

North of Howland Island

A “north of Howland Island” conclusion was largely that of the Itasca Captain Warner Thompson,

detailed in his Cruise Report dated 24 July 1937.68 CDR Thompson’s report is comprehensive. It details

good weather 40 miles around Howland Island on the morning of July 2, 1937, better to the south and

east. There were distant horizon clouds far to the north and west.

While perfectly understandable, and logical, to CDR Thompson at the time, from the foregoing analysis it

is possible that most of CDR Thompson’s linked assessments were incorrect.

• AE’s report of “clouds” and “overcast” conditions, and a final altitude of 1,000 feet, led CDR

Thompson to conclude the aircraft’s approach and descent to Howland Island must have been

from the west northwest direction.

o This was likely incorrect.

• CDR Thompson concluded no celestial fixes had been taken throughout the night.

o Again, this conclusion was likely incorrect.

• CDR Thompson assessed that a sun shot might have been obtained at sunrise in the vicinity of

Howland Island. He assumed a sun shot was made, and that a sun LOP was correctly computed,

and accurately placed over Howland Island.

o The sun shot assessment was likely correct, however, it is apparent that the sun LOP,

while a correct value (337-‐157 deg true), did not overlay Howland Island.

• CDR Thompson assumed that the sun’s glare was responsible for AE missing the island, Itasca,

and the smoke screen produced by Itasca to aid visual acquisition.

o This was likely a factor.

67 Eric Chater, Letter to Mr. M. E. Griffin. 68 Cruise Report 24 July, 1937 CDR Warner Thompson, Commanding Officer, Itasca (TIGHAR).



• CDR Thompson assumed that AE passed within 200 miles north of Howland Island, and ditched in

a sector bearing true 337-‐045 degrees from Howland Island (presumably the correct position of

Howland Island, 5.92 nm east of AE’s coordinates for Howland Island), at a distance between 40

and 200 miles.

o The evidence does not support this conclusion.

Position Reporting

The 0418 GMT In-flight position report

The 0418 GMT in-‐flight position report from AE was chronicled by Chater.69 This report contains only an

altitude, and the “140 knots” speed reference. The reported speed and altitude are valuable data.

Analysis concludes the speed is a true air speed.

The 0519 GMT In-flight position report anomaly

The reported point is approximately 220 nautical miles from Lae. The Electra covers this distance in 2

hours 18 minutes, far less than 5 hours.

Two sources of error were assessed.

1. The actual longitude at 0519 GMT was not W 150.7 degrees, but rather, W 157.0 degrees.

2. The 0519 GMT time reported was actually at 0219 GMT.

Coordinate Transposed

The transposed coordinate creates Path C, supported by these factors.

• This position, when contained in a flight path reconstruction, conforms to historic,

recommended, and/or statistical speeds and times demonstrated by AE.

• When contained in the mission path, this point results in all other reported points, times, speeds

and flight performance data, conforming to Electra capabilities, AE historical performance,

engineering recommendations, and pilot behaviors.

• Path C is a reasonable deviation around significant convective weather east of Lae.

• At the 157.0 west longitude position, islands are large and clearly visible, well charted, and allow

an accurate navigation position fix.

Time Error

It is possible that the report at 0519 GMT was actually made at 0219 GMT, with the error recorded as a

“5” instead of a “2.”

69 Eric Chater, Letter to Mr. M. E. Griffin.



• Supporting this theory is the Electra’s performance on the mission results in the aircraft passing

the reported position coordinates at 0218 GMT.

• Accepting the “Time Error Theory” creates Path B.


This report is made within visual sighting of Nukumanu Island, within 20 nautical miles of the island.

AE reports “winds 23 knots” which becomes a basis for every researcher’s calculations.

The reported aircraft altitude is consistent with preflight planning. The reported winds show that AE and

Fred had good navigation fixes and knew their winds – unfortunately, they just didn’t report the wind

direction, which is important to identify the headwind component, and subsequently, key flight speeds

and times.

The assumption that these were “headwinds” produces the 26.5 mph headwind component identified by

Long, and used by every author referring to this event.

Previous analysis results show that forecast and actual winds were very close at the 0718 GMT position,

but likely diminished after passing the Nauru Island area.

The 1030 GMT Visual Sighting of Nauru Island Lights

“A Ship in Sight Ahead”

AE reported seeing “…a ship in sight ahead…” at about 1030 GMT, according to Harold J. Barnes, officer

in charge of the radio station at Nauru Island who copied Earhart’s message.70

In a letter from Mr. T. H. Cude, Director of Police, Nauru Island, to Dr. Francis Holbrook of Fordham

University, he stated he heard AE broadcasting to Harold Barnes, Chief Wireless Operator at Nauru

Island, several times between 10-‐11 PM that she could see the lights on Nauru Island. The lights she

referred to were the flood-‐lights strung out along the two 1,000-‐foot cableways situated on top of the

island to permit mining at night.71

• Note that 10-‐11 PM on Nauru Island corresponds to 10-‐11 GMT.

The lights on Nauru Island were at an approximate elevation of 556 feet above sea level, and AE could

not have seen these lights until entering the visual horizon to Nauru Island at AE’s cruise altitude. The

Figure below shows the Electra’s arrival times on each Path A, B, and C, at the USS Ontario which was

assigned a station at the half-‐way point of the mission and in the vicinity of Nauru Island, entering the

visual horizon to Nauru Island, and relative to two positions estimated by researchers for the location of

the SS Myrtlebank.

70 Elgen Long, Amelia Earhart – The Mystery Solved, 20. 71 Laurance Safford, Amelia’s Flight Into Yesterday, (McLean, Virginia: Paladwr Press, 2003) 31-‐33.



• Any Path A, B, or C could result in AE reporting the Nauru Island lights at the times logged for her

reports.

At 1030, if USS Ontario was the ship referred to in AE’s in-‐flight position report, it does not make sense

the report would be, “a ship in sight ahead,” because on any Path, USS Ontario would have been behind

her.

The “ship in sight ahead” was likely the SS Myrtlebank. This is based on the navigation times, the visual

horizon distance to Nauru Island and AE’s proximity to SS Myrtlebank, the area of location of the SS

Myrtlebank on its voyage from New Zealand to Nauru Island, and the size of SS Myrtlebank at 420 feet, ,

and much larger, than the 185 foot USS Ontario.

• At 1030 GMT, only the SS Myrtlebank is “ahead” of AE on any Path A, B, or C.

This places AE in a location in time and space, from which the integrity of a flight path reconstruction,

and ultimately, the final location of wreckage, can be considered with some sense of confidence that AE

and FN were largely on course, and on track, to Howland Island, at 1030 GMT.

Figure 7 -‐ Penetration of the visual horizon to Nauru Island.




AE reports here, “about 200 miles out.” The Electra flight plan at this time shows the aircraft 204nm

from Howland Island (1937 coordinates). This is possibly the most accurate position, and report, of the

mission since the 0718 GMT report near a visible island.

This position was prepared by FN, likely using celestial navigation stars and/or planets with good

visibility. These provide the most accurate fixes, and this fix appears to have been very accurate.


AE reports here, “about 100 miles out.” This report is problematic because the Electra could not cover

100 miles in 30 minutes, and also, the Electra flight plan shows the aircraft at 146nm from Howland

Island (1937 coordinates). This report may reflect an estimated position, unlike the very accurate position

computed by FN 30 minutes earlier.

Aircraft Position – Report Correlation

The table below depicts the Electra position, on performance and path, at the times when these two

reports were made. Data supports that Path C was the likely path flown, and that the Electra’s position

on Path C at 1745 GMT resulted from very good celestial fixes.

Celestial fixes are much more accurate than a sun fix, which would have been used to prepare the 1815

GMT report.

Table 4 – Electra position on each Path at the time of these two in-‐flight position reports.

ROUTE 200 Miles Out 1745 GMT 100 Miles Out 1815 GMT

PATH A Great Circle 165 108

PATH B “Chater Point” 165 106

PATH C Choiseul Island 204 146

If these are accurate results, AE likely descended early, perhaps at 1825 GMT, in accordance with descent

specifications and past historical performance.

The result is the Path C End-‐of-‐Navigation point, short of Howland Island.



Fatigue and Human Factors

Research on fatigue, impairment, and cognitive function72 demonstrated that after 17 hours of sustained

wakefulness, cognitive psychomotor performance decreased to the equivalent performance impairment

at a blood alcohol concentration of 0.05%. At 24 hours of wakefulness, performance was equivalent to a

blood alcohol concentration of 0.10%.

Modern fatigue guidelines in human factors attempt to assure that employees are not on duty beyond 16

hours of wakefulness, with duty times ranging from approximately 8-‐16 hours, depending on industry

and regulatory requirements.

Both acute and chronic sleep loss affect fatigue, and can decrease performance.

AE and FN arrived in Lae, Papua New Guinea73 on the afternoon of Tuesday, June 29, 1937. They’d been

on duty for 30 consecutive days, largely flying 1 mission per day averaging 5.1 hours flying per day. For

the previous 7 flying days, only two flights exceeded 5 hours, and five flights were much less than 5

hours.

• There were 3 days in Bandoeng, from June 21-‐23, for aircraft maintenance and no flying.

• June 24 and June 25 were flying days.

• June 26 was a non-‐flying day again, in Bandoeng, where AE returned for maintenance repairs.

• June 27-‐29 were flying days.

• June 29 included 7 hours 40 minutes from Darwin, Australia to Lae, New Guinea.74

• June 30 was a non-‐flying day, however, AE was at work on radio traffic at 0615, and testing

aircraft radios at noon.

• On July 1 at 0635

o AE conducted a short, 30-‐minute test flight.

o FN got a time signal check at 2220 local time.

• On July 2 at 0800, FN got another time signal check.

• On July 2, AE departed Lae at 1000 local time.

In the 11 days from June 21-‐July 1, 5 days were non-‐flying days, and 5 days were flying days.

In the 72 hours before departing Lae, AE flew 7 hours 40 minutes Darwin to Lae, and a 30-‐minute test

flight, for a total of 8 hours 10 minutes, in two days of flying.

72 “Fatigue, alcohol and performance impairment,” Dawson and Reid, The Queen Elizabeth Hospital, Woodville, South Australia, 17 July 1997 73 Purdue University, George Palmer Putnam Collection of Amelia Earhart Papers 74 Eric Chater, Letter to Mr. M. E. Griffin, 3.



It is likely AE and FN rested normally June 29, June 30, and July 1. Arising early was AE’s standard

habitual norm on the World Flight, and that was adhered to while in Lae.

The Human Factors conclusions are that AE and FN were reasonably well rested in Lae, with two days of

non-‐flying (excepting the early and short test flight) before departing on the final Lae to Howland

segment. They had relatively short duty days during the past 7 flying days, with no reports or indications

of acute sleep loss, and no illness reported.

July 1 was an early, but normal day for both crewmembers, and afforded a reasonable sleep opportunity

prior to arising for their flight to Howland.

Previous World Flight mission flight times ranged from 0.87 to 13.37 hours, with a mean flight segment,

or “stage length” of 5.1 hours. Standard deviation for this data is 3.22 hours. Ninety-‐five percent of the

World Flight stage length flight times were less than 11.5 hours.

The Lae-‐Howland segment was 65% longer than most of the previous mission segments. AE and FN

appear to have conscientiously prepared for their mission to Howland, were well rested prior to

commencing this challenging segment, and from a Human Factors perspective, the conclusion is that no

extraordinary pre-‐mission factors adversely affected preparations and rest for the Pacific crossing.

The Lae to Howland segment included approximately a 24-‐hour continuous duty period. FN was getting a

time check at 0800 local time and AE was likely already at the aircraft. Both likely arose at approximately

0500-‐0600, if not slightly earlier. They would be awake for 23 hours when they reported “on you” at

1912 GMT on July 2, after concluding the most demanding navigation and landing site acquisition

challenge of the entire World Flight.

Despite their rested beginning to the Lae-‐Howland flight segment, their time-‐on-‐task and time awake

combined to increase fatigue and risk. This reduced human performance to levels associated with

alcohol-‐related cognitive impairment at 0.10% concentration of blood alcohol, likely interfered with

terminal maneuvering, radio work, searching, and visual acquisition of Howland Island or Itasca.

At this level of fatigue, significant challenges to fly the aircraft at lower altitudes, operate radio

equipment that was, to some extent, unfamiliar and untested, navigate and visually search for Howland

Island proved to be insurmountable.

The implications of this accident scenario, whether a water impact resulted from fatigue or fuel

exhaustion, are that the aircraft location should be relatively close to its estimated end-‐of-‐navigation

position.

Celestial Navigation

Below are the July 2, 1937 celestial opportunities for key navigational fixes along the route from Lae to

Howland Island.



In general the sky was still quite bright during the time the Electra passed the position of USS Ontario.

Combined with the ship’s small size, it is possible that USS Ontario was not visually acquired by AE or FN.

Subsequent to passing the USS Ontario’s position, a darkening sky would have enhanced celestial

navigation opportunities, with consideration for weather. Navigation stars, weather permitting, were

available from the side view cabin windows, where FN conducted his navigation and charting.

The implications of these conditions and celestial body positions in the night sky, were that no radical

aircraft course changes were necessary for FN to take good celestial fixes on stars, which facilitated a

higher probability that the aircraft could accurately remain on a track to Howland Island.

Numerous sight reduction table corrections, required to be applied to a star fix, are additional sources of

potential error. Although FN was among the best navigators of his day, cumulative fatigue throughout

this flight segment could have resulted in errors. The data shows this is not likely, but always possible.

On Path C the 1745 GMT report at “200 miles out” was made at 204 nm from the 1937 position of

Howland Island, likely from good celestial navigation fixes, and likely very accurate. The 1815 GMT

report at “100 miles out” was made at 146 nm from Howland Island.

If the first report was accurate, a refraction calculation error at AE’s altitudes could produce the error

evident in the second report. This error would result in AE descending early, and arriving early, to what

they thought would be Howland Island. AE may also have simply estimated the “about 100 miles out”

position, and started an early descent, with no FN errors involved.

Below is a table of position reports and the primary stars available to FN for celestial navigation.

Weather was reported by Itasca as good, and likely good en route. AE’s report of “overcast” skies is

possibly a report of an “undercast” because along with these reports on previous segments, she adds the

report of good visibility for navigational celestial fixes.

Position Report Time and Corresponding Celestial Opportunities

Table 5 -‐ PUB 249 Air Almanac of available stars on the Lae-‐Howland segment, with brightness magnitudes

0718 GMT Position Report

Sun

0930 GMT at Ontario Position

Arcturus 0.2

Vega 0.1

Spica 1.2

Antares 1.2

Regulus 1.3

1041 GMT Abeam Nauru Island, SS Myrtlebank

Arcturus 0.2

Vega 0.1

Spica 1.2

Antares 1.2

Regulus 1.3

Jupiter -‐2.8

Altair 0.9

Acrux 1.1

Mars -‐3.0

1745 GMT “200 out”

Deneb 1.3

Vega 0.1

Fomalhaut 1.3

Acherner 0.6

Venus -‐3.7

Jupiter -‐2.8

Moon -‐12.6 Full

Saturn -‐0.24



1815 GMT “100 out”

Deneb 1.3

Vega 0.1

Fomalhaut 1.3

Acherner 0.6

Venus -‐3.7

Jupiter -‐2.8

Moon -‐12.6 Full

Saturn -‐0.24

Alderbaran 1.1

The faintest stars visible to the naked eye under perfect conditions are magnitude 6.5. Brighter stars

have lower magnitudes, with negative numbers indicating very bright stars. The brightest star is Sirius at

magnitude -‐1.6.

Throughout the evening hours from Lae to Howland, there is no moon visible because its elevation is

below the horizon. The moon rises early at 0123 Howland local time in the morning and sets at midday

1351 local time. Thus, bright stars are more visible without moonlight.

The official sunrise at Howland is contained in the following US Naval Observatory data. Civil twilight

begins in the morning when the geometric center of the Sun is 6° below the horizon, and ends at sunrise.

The angular diameter of the sun is 0.5 degrees. At civil twilight, bright stars and planets are visible, and

outdoor activities may proceed with no additional illumination.

At civil twilight on Howland Island, on July 2, 1937, the Sun’s azimuth is 067 degrees true, the moon

azimuth is 38.5 degrees true, or approximately 30 degrees left of AE’s inbound course. The moon

elevation is 73.4 degrees, with an illumination of 37%. The moon is visible during the final hours inbound

to Howland Island.



Figure 8 -‐ Important data for Howland Island.



A Line of Position Approach Unlikely

If AE had taken a course change at where she thought “about 100 miles out” was at 1815 GMT, a 30

degree course change to intercept a line of position would require approximately 45 minutes to a LOP

turn point that lies on a bearing 337 true or 157 true at 40nm from the end-‐of-‐navigation point.

AE would have intended this EON point as Howland Island. The LOP would actually lie well short of

Howland Island.

Time at the turn point would be 1900 GMT, with another 40nm remaining on the LOP.

The LOP segment would require 20 minutes to the EON point at 1920 GMT.

If AE had flown the LOP, they may not have reported “on you” at 1912 GMT.

Instead, the flight modeling data indicates AE flew a direct course during descent towards an EON point,

which she presumed would be Howland Island, and where she anticipated a DF steer to the Itasca, with

visual acquisition of Howland Island’s landing strip.

Regardless of whether or not AE flew a LOP, the EON point for the LOP is virtually co-‐located with the

EON point for a straight in descent, at 1912 GMT. The aircraft is effectively at the same EON position for

either terminal flight track.

Sun Rise and the LOP

AE and FN defined their 337-‐157 line of position from the line orthogonal to the sun’s azimuth of 067

degrees true at sunrise on Howland Island, as they continued inbound at 8,000 feet. The distance to the

Path C EON point at the time of the 1815 GMT report “about 100 miles out” was 146nm. If a sunrise fix

was used to compute this position estimate, the 46nm difference between the reported distance and the

actual aircraft position is in the range of a refraction error to a sun fix. It exceeds the standard 15-‐30nm

accuracy of 1937 celestial navigation.

Adjusting latitude by +/-‐ 3 degrees to approximate a lateral course error of 180nm results in the sun

azimuth of a sun shot remaining at approximately 067 degrees true. The 337-‐157 degrees true LOP value

gives us no information as to the potential for a lateral position error when the sun fix was taken.

Advancing longitude has no effect on the value of the 337-‐157 degrees true LOP. Again, the LOP value

gives us no information as to the potential for an along-‐track error.

Advancing the time to 1928 GMT to 2013 GMT produces a line of position at 333-‐153 degrees true. This

gives us information that FN’s 337-‐157 degrees true LOP was based on a sunrise fix.



This reasoning supports that the “about 100 miles out” report was made possibly using a sun shot for

this position fix (stars would not be visible), with a possible error that caused the aircraft position to be

further from Howland Island than the calculations showed. This may have led to an early descent to the

EON point, because descents were made at approximately 70-‐80nm from the destination, leaving the

aircraft at the EON point, short of Howland Island.

The search grids are oriented around the Path C EON point to the west, and the Path A and B EON points

to the northeast of the 1937 Howland Island coordinates.

Part V. The Final Search Grid

Search Grid Orientation

The sunrise azimuth at Howland Island of 067 produced the perpendicular Line of Position of 337-‐157

degrees. Since the sun azimuth is in true degrees, the 337-‐157 degree Line of Position (LOP) should also

be in true degrees. However, in practice, AE may have flown along the LOP on a magetic heading of 337-‐

157 degrees. Our final search grid is oriented to a 337-‐157 degrees magnetic LOP, reflecting what AE

likely flew. The difference in search grid coverage between orienting the grids using true or magnetic

degrees, is not significant.



Final Search Grid

Standard Grid

This is the final search grid. Terminal area maneuvering, as well as wind effects on the flight’s EON point

are contained in these search grids.



Bathymetric Grid

This NOAA image includes the bathymetric characteristics of the search area.



Search Strategy Considerations

Debris Field

Following the Natal-‐Dakar flight segment, AE describes a project conducted during the World Flight in

which air samples were being taken, in a study of upper air microorganisms.75

These were performed by AE and FN for Dr. Fred C. Meier of the Department of Agriculture, and were

similar to experiments carried out on some of Charles Lindbergh’s flights. The collection devices were

aluminum cylinders, and AE reported having a supply aboard exceeding a dozen broomstick-‐sized

collection cylinders. These were mentioned in AE’s logs and the Luke Field aircraft inventory established

following the initial westbound World Flight attempt and crash at Luke Field.

These cylinders, if distributed post-‐impact, would be characteristic shapes in a debris field that could be

used to assist in identifying the wreckage.

In Situ Documentation

Ideally the entire structure should be documented as it is found, from as many angles as possible for 360

degrees around the wreckage. Interest areas include

• Condition of fuselage, wings, engines, propellers, flaps, and control surfaces.

o Impact damage is important to computing impact dynamics.

• Debris field mapping and geo-‐referencing of anything found in the debris field.

• If possible, cockpit documentation of controls, instrument indications, and items found in the

cockpit are valuable to the crash analysis.

Accident investigators should be on-‐site to observe and record information prior to recovery, and to

examine wreckage as it is recovered.

Aircraft Views and Dimensions

Dimensional Data

Below are basic dimensional data for a Lockheed 10A airframe. AE’s Lockheed 10E had larger engines

and other modifications.

75 Amelia Earhart, Last Flight, 133.



Figure 9 -‐ From Purdue's Collection – Basic Data – From Lockheed, Burbank, CA.



Figure 10 -‐ From Purdue's Collection -‐ Three-‐view Drawings.



Exemplars

Below are basic images for general structural reference.



Prior Work Review

Long, Elgen M. and Marie K.

Amelia Earhart – The Mystery Solved (Simon & Schuster, 1999)

Long’s research is by far, the most complete, comprehensive, and accurate work done to locate this

accident aircraft. Documentation of the entire mission is very thorough, and where literary license is

taken to craft the publication, it does not materially detract from the research work.

Rather than reiterate Long’s extensive analysis, the following are significant points as they relate to our

work in review, analysis, and aircraft localization:

• Valid assessment of headwind at 23 knots, 26.5 mph throughout mission.

o We investigate reduced headwind and increased crosswind effects on final position.

o These effects are contained in the Primary Search Grids.

• Flight path Lae-‐Howland passes through three points that are updated.

o No evidence the flight was at the point reported at 0519 GMT.

Long’s path through this point may simply conform to tradition.

o No evidence the flight passed directly over the SS Myrtlebank.

This point is 40-‐60nm north of track from Lae to Howland.

There is no evidence the flight did not overfly SS Myrtlebank, and the final End-‐

of-‐Navigation point(s) should not be affected by the small lateral track deviation

abeam Nauru Island, if indeed, AE was slightly closer to Nauru and did fly closer

to SS Myrtlebank.

o No evidence the flight was north of track, or Howland, at any time

This conclusion appears to have come from CDR Thompson of Itasca

• Distance and time averages are valid assessments, remarkably accurate for the analysis methods

used, and comprise a very credible basis for track plot and terminal area arrival at Howland.

o Validates an arrival near Howland with insufficient fuel to exit the Howland area

• Long creates a reference to “Itasca standard time (IST)” in addition to the already confusing

Howland Standard Time and GMT references.

• Long advances a compounding 10% of navigation distance error model, that, while somewhat

subjective and lacking of a more rigorous analytical conclusion, is a reasonable approach to a

location methodology.



Swenson, G., Culick, F.E.C.

Analysis of Amelia Earhart’s Final Flight – July 2, 1937

This research is well done. The engineering assessments are based on L487 and wind tunnel testing

performed in 1935 and contained in a test report, GALCIT Report No. 161P. Standard aerodynamics

equations are applied to determine performance.

Assumptions underlying this research include:

1. The magnitude of headwinds and their constant velocity throughout the entire flight.

a. This value, from Long, was 26.5 mph.

2. A constant true air speed flown throughout the entire flight.

a. This value, From Long, was 161.5 mph.

3. Initial fuel load.

a. This initial value was reported by Chater and Collopy.

b. Swenson and Culick, et al, applied adjustments for temperature and volume to arrive at

an initial fuel load of 1080 gallons, vice the value of 1100 gallons reported by Collopy.

4. Flight Path.

a. The authors used the path constructed by Long.

5. Altitudes.

a. The authors used In-‐flight position reports as the basis for reconstructing the vertical

flight path profile between Lae and Howland Island.

6. Ship Sighting.

a. The authors addressed the relative reliability in the 1030 ship sighting report by AE

i. They concluded that the vessel observed was either the USS Ontario, or SS

Myrtlebank.

b. Their assessment is based on assumed aircraft ground speed and time to the ship

sighting, and a projection forward to the Howland area arrival time. This helps to

establish a time abeam Nauru Island, in their path reconstruction.

The authors’ work is very credible. They presented a good baseline fuel consumption analysis, and

created numerous alternate scenarios as functions of headwind, fuel consumption and error tolerance.

Their assumptions for headwind, aircraft true air speed, initial fuel load, fuel consumption and endurance

are appropriate given the scarcity of facts. Their conclusions are valuable and interesting in assessing

boundary values for mission parameters.

The authors’ choice to use Long’s 26.5 mph headwinds is prudent and replicated by virtually all

researchers. Similarly, assuming aircraft true airspeed of 161.5 mph is considered valid.



Swenson and Culick and Long plot AE’s flight path at the ship sighting as passing over the assumed ship’s

position, which very slightly affects distance, timing, and position.

Swenson and Culick do not project this path point, slightly north of the great circle direct route

from Lae to Howland (Path A), to an end point north of Howland, as Long does.

Swenson and Culick’s path from the ship sighting converges to Path A as it proceeds direct to

Howland from the ship sighting point.

The Swenson and Culick, et al, conclusions below, are validated as follows

1. Initial fuel load and preflight planning should have enabled flight for 20 hours 38 minutes.

2. Actual mission time to initial arrival near Howland was 19 hours 12 minutes.

3. This should have allowed post-‐arrival endurance of 1 hour 16 minutes.

4. The ship sighted was SS Myrtlebank, based on assumed average headwind and aircraft ground

speed and time, and projecting those parameters forward to an estimated arrival at Howland at

1912 GMT.

5. AE was within 100 miles [units not specified] of Howland based on radio strength.

6. “…AE’s flight…ended in the ocean short of her intended landing place.”

Safford, Laurance

Earhart’s Flight Into Yesterday – The Facts Without the Fiction (Paladwr Press, 2003)

Captain Laurance Safford passed away before this book was published. Co-‐editors Cameron Warren and

Bob Payne salvaged the original manuscript and its supporting exhibits, presenting the work in this

publication. Most of Safford’s work involves the communications in the planning and search phases of

the mission. Safford devotes only 38 of 199 pages to the actual Lae to Howland mission segment. Most

of his work is with radio logs and communications, coordination, control (operational as well as

administrative), and the search effort.

This is no surprise as Captain Safford’s Navy career was in Cryptology, and Intelligence.

Safford’s conclusion (p115) is that AE crashed at N 01.00 degrees and E 178.00 degrees, with a 95%

probability of a final position within 100 miles [units not specified] of this location.

• This is approximately 325 miles [units not specified] west of Howland Island.

Safford’s inclusion of logs, messages, radio communications, and the attention to command and control

issues associated with the mission planning and conduct of search operations, is valuable in adding

background detail to our overall analysis.

Perhaps the most valuable information from Safford concerns the Itasca search patterns, and search

decisions, made by its commanding officer, CDR Thompson. In his messaged assessment to COMDESRON

2, CDR Thompson concluded that AE was within 250 miles [units not specified] of Itasca, based on signal



strength, and went down within 250 miles [units not specified] of Howland Island between 337 degrees

and 45 degrees true and not nearer than 30 miles [units not specified].

CDR Thompson and Itasca assumed AE had laterally deviated north and had overflown Howland.

Safford is critical of many elements of this mission and his work does a credible job of detailing errors

and inconsistencies.

Nesbit, Roy

Missing Believed Killed (Sutton Publishing LTD, 2002)

In this work detailing the accounts of famous missing persons, the author devotes 34 pages in a total 173

pages to AE’s life and final flight. The book is an account of 5 accidents involving famous people.

The author details the Electra aircraft from Lockheed documents, including interesting details concerning

fuel tank arrangements and capacities, previous flight segments, aircraft weights and speeds, flight

times and position.

• The author depicts a flight path directly over Nauru Island, assuming this path from the AE report

of seeing Nauru Island’s lights. This path discounts the involvement of USS Ontario, and SS

Myrtlebank, but validates identifying lights on Nauru Island.

Most interesting and valuable are the author’s references to celestial navigation, and the effect on the

Lae-‐Howland flight from various aspects of celestial navigation, including navigation errors. The author is

an experienced aircraft navigator, with experience near the era of AE’s World Flight and with the USAAF

in WWII.

The author “recreates” an assumed series of actions taken inside the Electra, by Fred Noonan and

centered on celestial navigation, during the final portion of the flight.

This recreation begins with the AE In-‐flight position report of 200 miles out [units not specified] at 1745

GMT, and includes a proposed resolution of this position, with the next report at 1815 of 100 miles out

[units not specified].

The author generally concludes that these reports are consistent with an increasing accuracy of

navigation provided by the fixing of position based on sunrise. Further, the author discusses the Line of

Position, how it is used, and how it may have been used by Noonan, if he used such a technique at all. No

conclusions are provided.

The author details (p26) one source of navigation error in using a sun fix at sunrise. The error arises in

defining the sunrise time, and angle to the sun itself, at the time of first sighting of the rising sun.

• “On the sea, the angle is essentially zero, however, in an aircraft at altitude, the occupants view

the sun rise at an earlier time than if viewed from the sea surface. This difference is accounted



for by correction factors in sight reduction tables.” Failing to correct a sun shot for this angular

value, according to the author [no mile units specified], results in a 31-‐mile error at 1000 feet, 44

miles at 2000 feet, 70 miles at 5000 feet.

• This error produces an aircraft position that is closer to Howland than the actual aircraft

position. Further, the author contends that the “200 miles out” report was more accurate than

the “100 miles out” report, if this error were made.

• The author concludes this error was made, and that AE was flying north and south along a Sun

Line of Position, located at least 31 miles [units not specified] west of Howland Island.

In general, the author publishes interesting aircraft information, and covers the celestial navigation

issues and error potential very well.

The work concludes that a sun shot error produced a final position at least 31 miles west of Howland

Island, and that AE had flown north and south along a 337-‐157 line through this position.



Pellegreno, Ann Holtgren

World Flight – The Earhart Trail (The Iowa State University Press, 1971)

Valuable data from this 1967 Commemorative Flight includes references to climb speed of 100-‐120 mph,

and 20 minutes time to climb to 1000 feet after a gross weight takeoff. This reference is made twice and

the author comments that this is normal performance for her Electra.

The author cites several cruise performance values which provide good comparisons for AE mission

analysis, in speed and fuel consumption, despite flying an Electra model 10A with smaller engines, but

effectively the same horsepower-‐to-‐weight ratio, as for AE’s Electra 10E.

The author also cites en route winds throughout the flight from Lae to Nauru Island, indicating useful

information about the behavior of en route winds in this area.

Pellegrino cites work published by Polhemus (p208) in which Polhemus calculates AE’s initial fuel at Lae

at 900 gallons, and that AE executed a direct (great circle) flight path to Howland. Polhemus estimates

AE’s final position “…in the vicinity of Howland Island….”

Near Howland Island, as Pellegreno was flying on the Line of Position heading 157 degrees at 1905 GMT

(p160), a squall appeared over where Howland Island should be. The flight adjusted course slightly to

avoid the squall, but continued to pursue visual acquisition of the island.

With pilot Pellegreno flying, and two dedicated observers (one in the cockpit right seat and one in the

cabin), Howland Island could not be found until approximately 1957 GMT, when the person in the cabin

spotted what he thought was land. They had less than 20 minutes remaining fuel on station to devote to

the search for the Island, and as Pellegreno later said, “we nearly missed it.” This, after searching for

nearly an hour.

They were approximately 10-‐12 miles [units not specified] north of Howland Island at the moment they

visually acquired the island.

Pelllegreno’s account of her thoughts and feelings upon arriving and not seeing Howland, then

conducting a protracted search with limited fuel resources, is extremely interesting as a human factors

and operational comparison to what may have occurred on AE’s mission. Pellegreno writes a compelling

narrative here, one that can not help but evoke a sense of urgency, desperation, and elevated tension.

Pellegreno’s flight had the advantage of better navigation equipment, a third set of human eyes, a

nearby ship providing good DF bearings, and the luxury of having departed Nauru Island, with a Canton

Island destination. With all of these advantages, they nearly missed visually acquiring Howland Island.

This account demonstrates the great challenge attempted by Amelia and Fred, and provides a good

assessment of the difficulty in visually acquiring tiny Howland Island.



Finch, Linda

No Limits (World Flight, Inc., 1996)

This account of preparations for a 1997 Commemorative Flight details most known facts and

assumptions concerning AE’s flight from Lae to Howland Island.

Strippel, Dick

Amelia Earhart – The Myth and the Reality (Exposition Press, 1972)

The author concludes that initial fuel load was 980 gallons, based on two calculations

• A gross weight and takeoff distance analysis for Lae’s grass airfield in 1937, that results in a

possible takeoff weight and fuel load.

The author concludes the ship sighted was USS Ontario because had it been SS Myrtlebank, the position

and time error would have exceeded Noonan’s standard performance for navigation accuracy.

The author recounts a number of scenario theories, possible errors, and the effects of those errors.

The only actual position statement in this work is from Captain J.S. Dowell of the USS Lexington (p156)

who concludes “…at 2030 the plane landed on the sea to the northwest of Howland Island, within 120

miles [units not specified] of the island.”

The author’s Appendices contain interesting and useful information regarding aircraft configuration,

performance, and some details of the declassified messages and logs contained in national archives.

Gillespie, Ric

Finding Amelia – The True Story of the Earhart Disappearance (Naval Institute Press, 2006)

The International Group for Historic Aircraft Recovery (TIGHAR) and the author have compiled a

comprehensive and useful website, and this publication, including a resource CD containing AE-‐related

information, research and data.

This work supports an alternate theory that AE landed the Electra on Gardner Island in the 1937 Phoenix

Island Group. Gardner Island is now Nikumaroro Island in the Republic of Kiribati, approximately 400

statute miles southeast of Howland Island.

This theory emanates from essentially the immediate four-‐day period following the disappearance of AE,

information for up to two weeks following the disappearance of AE, and multiple expeditions to

Nikumaroro by TIGHAR personnel during which artifacts were found that are claimed to possibly be

linked to the AE mission. These artifacts have not yet been validated or documented as coming from AE’s

mission, however, the discoveries are interesting.



Main support for the theory comes from analysis of radio transmissions allegedly made by AE, and

received by experienced radio operators at Honolulu, Wake Island, and Midway Island radio operator

stations.

The signals and attempted direction finding (DF) bearings from these three stations converge somewhat

close to Gardner Island, lending to TIGHAR’s theory that AE crash landed the Electra on Gardner or very

near it, making landfall and transmitting radio calls.

Numerous challenges exist in these theories, not the least of which is whether or not the Electra could

have flown to Gardner Island at all, or transmit any signal with inoperative engines and generators, or do

so following an off-‐field landing or water ditching.

Interestingly, the best DF bearings on good, strong radio signals in 1937 contained some directional

variance under the best conditions. If the DF bearing signals received by Honolulu, and Midway Island

are adjusted by a 10 degree variability in directional reliability, and in the direction of common sense

toward the area most likely containing the Electra, and the Wake Island bearing is given a +/-‐10 degree

azimuth variance since it was reported as a strong signal and bearing, the area bounded by the

convergence of these adjusted signal directions is a centroid approximately 90-‐123 nm southwest of

Howland Island, and 260nm northwest of Gardner Island. Questions remain concerning whether or not

the Electra could transmit these radio signals following a water ditching, if AE had any backup or

portable radio transmitting equipment aboard the Electra on the Lae-‐Howland mission segment, or if a

life raft was aboard the Electra, which AE may have occupied while transmitting and drifting towards

Gardner Island. The research of many investigators indicates that flying a total of more than 4 hours fuel

after 1912 GMT, is not likely. If AE’s last transmission was at 2013 GMT, an hour after arriving at

Howland, and they commenced a divert to Gardner Island, then AE would have had to arrive at Howland

Island with more than 5 hours fuel remaining.

Swenson and Culick’s thorough aerodynamic analysis precludes such a fuel state, and other researchers

corroborate these findings.

However, the author makes some compelling arguments for TIGHAR’s theories, discusses interesting

discoveries made on Nikomororo Island, and provides evidence to consider TIGHAR’s alternative theories.

CDR Thompson, Commanding Officer, Itasca

Itasca’s commanding officer was certain that AE had crashed into the sea between 337 and 045 degrees

from Howland at up to 250 miles [units not specified]. This belief directed Itasca’s initial search efforts,

however, it was never really clear from any historic account, why CDR Thompson felt the aircraft was so

far north of Howland Island.

The only clue to what may have justified this assessment in CDR Thompson’s own mind, is his belief that

had AE been south, they would have visually acquired either Baker or Howland Island, the Itasca, the



smoke being created by Itasca, and that missing all of this was clear evidence of the aircraft being far to

the north.

Hewlett Schlereth

Celestial Navigation in a Nutshell (Sheridan House, 2000)

The author provides an excellent primer in the process, mechanics, and administrative details for

executing celestial navigation.

The dip angle or refraction error is among other errors well explained.

This work is an excellent background in understanding what occurs in celestial navigation.

Earhart, Amelia

Last Flight (Harcourt, Brace and Company, 1937)

This critically important work provides the only record of the World Flight, AE’s flight log information,

operational and administrative data, and insight into human factors and behaviors relevant to the World

Flight mission segments.

The publication is a collection of writings from AE to her husband, George Palmer Putnam, who published

the book in the same year AE was missing on the World Flight mission.

The value of this work is immeasurable.

Signal Strength and Distance

Signal strength is an unreliable indicator of distance, however, the Itasca logged signal strengths of AE

in-‐flight position reports, and it is worthy to examine this data.

The chart below shows AE’s approximate distance from Itasca for each of AE’s en route position reports.

No specific conclusions can be made from this data, although, it has merit for qualitative assessments.

Final AE radio transmissions were logged with strong signal strengths, alluding to an aircraft very near

the Itasca.



Figure 11 – Radio Signal Strength versus Distance Plot.

R² = 0.80495

R² = 0.99636

0

1

2

3

4

5

6

-‐100 0 100 200 300 400 500 600 700

SIGNAL STRENGTH vs Distance (nm)

SIGNAL STRENGTH

Linear(SIGNAL STRENGTH)

Linear Forecast 50nm shows ~5 therefore 5+ could be <50 nm.

Poly forecast 50nm shows ~3-‐4. Signal Strength to Distance relaUonship is not well defined.



APPENDIX

Search Strategy Refinement

Abbreviations

• AE -‐ Amelia Earhart

• BHP -‐ Brake Horse Power

• CFIT -‐ Controlled Flight Into Terrain

• EON -‐ End of Navigation Point

• FN -‐ Fred Noonan

• GPH -‐ US Gallons Per Hour

• LOP -‐ Line of Position

• L487 -‐ Lockheed and Kelly Johnson Report 487

• SFC -‐ Specific Fuel Consumption (lbs/BHP/hr)

Search Grid and Scenarios

The challenge to identify a starting point in the overall search grid requires a detailed fuel consumption

analysis and a consideration of lost aircraft location theories.

We agree with Long and other researchers that NR 16020 was not lost en route, did not land at Howland

or Baker Island, and lacked sufficient fuel (shown later) to reach any other land mass. Therefore, we

focus on a failure to arrive scenario, where the aircraft possibly crashed, experienced a Controlled Flight

Into Terrain (CFIT) event, or exhausted its fuel supply.

• A crash event could result from a loss of control, or a mechanical malfunction.

• A CFIT event is an inadvertent collision with terrain (water), often involving a loss of situational

awareness, but with the aircraft flying normally in terms of configuration, speed and attitude.

o Flying over smooth water conditions reported by Itasca, is a challenge.

o Depth perception is more difficult than while flying over rougher seas.

• A fuel exhaustion event could produce a survivable, controlled water ditching.



Various calculations result in sufficient fuel at 1912 GMT to conduct a 1.5-‐4.0 hour search, but more

likely a search in the range of 1.5-‐3.1 hours. After 2013 GMT, the total absence of radio communications

is unusual, supporting two possibilities.

1. The aircraft may have impacted the water prior to fuel exhaustion.

2. Fuel exhaustion precluded further radio communications. This could result from a mission fuel

over-‐burn for unknown reasons. For example

a. Zero fuel at 2030 GMT would indicate a mission over-‐burn of 71 gallons.

b. Zero fuel at 2100 GMT would indicate a mission over-‐burn of 51 gallons.

These examples represent a 2.4 to 3.5 GPH variance in total fuel consumption from planning

calculations. The per-‐engine fuel use variance of 1.2 to 1.75 GPH is certainly possible.

A search strategy requires calculation of where the aircraft is in time and space, and how much fuel and

time remained, after arriving in the Howland area at 1912 GMT.

Reference Grids

Reference points are plotted in the search grids, including the Path C End of Navigation (EON) point and

a 2013 GMT position.

There is evidence that winds in the final 8.5 hours of the mission either decreased in headwind

component, and/or shifted direction to come from slightly left of course and at reduced strength.

In order to address the effects of winds that may not have been detected or accounted for by AE and FN,

an analysis was completed for a range of possible wind values. This analysis applied various realistic

wind values to fixed headings the crew could have maintained. The resulting End of Navigation points

are contained in the existing search grid.

The Search Plan is oriented along a 337-‐157 degrees magnetic compass heading, perpendicular to the

planned magnetic ground track from Lae to Howland. The Search Plan accounts for possible cross-‐track

error en route, as well as subsequent Line of Position (LOP) ground tracks in the terminal area as

functions of true or magnetic tracks.

The LOP established by FN at Howland sunrise in preparation for AE’s “about 100 miles out” position

report at 1815 GMT, was 337-‐157 degrees true.

We assess AE did not fly the LOP initially, nor until at least 1928 GMT (“…circling…”), when they reported

flying the LOP at 2013 GMT.

At 2013 GMT, AE reported, “WE ARE ON THE LINE OF POSITION 157-‐337, WILL REPEAT THIS MESSAGE.

WE WILL REPEAT THIS MESSAGE ON 6210 KCS. WAIT LISTENING ON 6210 KCS. WE ARE RUNNING NORTH

AND SOUTH.”



This report is 61 minutes after initial arrival at where they thought Howland Island was, following an

initial search of the area. After the “circling” report at 1928 GMT, they likely commenced flying the LOP

tracks in a rectangular pattern, progressing further east on each LOP, while attempting to contact Itasca

and visually acquire Howland Island.

Anxiety was reported in AE’s 2013 GMT radio transmission. It would be possible that under the

circumstances, AE flew northwest on a heading of 337 degrees magnetic.

not accounting for a magnetic variation correction to FN’s LOP if it was indeed in degrees True.

The 10-‐degree difference between true and magnetic courses in search grid orientation was constructed

to examine positional effects on search operations.

The effect of this orientation is insignificant.

Fuel Remaining

The amount of fuel remaining in the Electra at 1912 GMT is important because it determines how long

the aircraft could stay airborne, and how far it could fly, before fuel exhaustion.

The amount of fuel remaining is a function of how much fuel was consumed.

This analysis is a challenge due to the need for estimation in the absence of empirical data.

Direct evidence from AE, and World Flight data, corroborate that mission segments were flown

adhering closely to the accurate Kelly Johnson specifications.

It was not possible to conduct test flights on the aircraft to acquire necessary performance data because

there are very few remaining Lockheed Electra 10E aircraft. The one article we photo-‐documented is not

flyable.

In order to make an assessment of fuel consumption, and the possible amount remaining, other data

were examined.

Fuel Consumption

Constants used in this analysis are

• Fuel weight is 6 pounds per gallon (also used by Swenson and Culick).

• Maximum endurance speed is 120 mph at 40 GPH.

o Estimated from L487 and Pratt-‐Whitney engine data (35-‐40 GPH).

• Takeoff fuel quantity is 1080 US gallons (Swenson and Culick).

The following resources were examined



• Kelly Johnson Telegrams.

• “Range Study of Lockheed Electra Bi-‐Motor Airplane,” Lockheed Report 487 dated 4 June 1936.

• AE Flight Notes, Flight Performance history, and direct evidence of performance.

• “Aircraft Engine Characteristics Summary,” Pratt-‐Whitney dated 1 May 1951.

• “Flight Operation Instruction Chart,” detailing aircraft performance for the North American AT-‐6

SNJ with the Pratt-‐Whitney R-‐1340-‐AN-‐1 (very similar to –S3H1).

• Jeppesen Flight Planning software interpolating L487, Kelly Johnson and AE Flight Notes data.

Each of these resources is limited to some extent, in its usefulness.

• Lockheed Report 487 is largely analytical, reflecting computations vice actual aircraft

performance. The L487 Report includes brake horsepower, however, it does not specifically cover

engine power settings frequently used and reported by AE in her flight notes.

• None of the three Kelly Johnson telegrams (issued post-‐L487 Report) containing flight test data

mention the gross weight of the Electra as tested, the speed associated with each power setting,

outside air temperature, or the brake horsepower at which fuel consumption data were

recorded.

From the Kelly Johnson flight test data, notably the third Telegram to AE, mission profile

recommendations were made for altitude, power setting, and fuel consumption. These recommended

settings were grouped into 3-‐hour segments, reflecting that Electra aircraft performance is relatively

unaffected by small gross weight changes.



Aircraft Gross Weight

The gross weight of the aircraft and the power from its engines are important to climb rate, cruise speed,

and fuel consumption.

For constant altitude, constant speed cruise flight, lift must balance weight, and engine power must

balance the total vehicle drag from all sources.

An aircraft design axiom is that an “aircraft climbs on its engines.” Excess engine power beyond that

required for cruise flight where vehicle drag is balanced by engine power, can be used to climb, and

where excess power is limited, climb rate is also limited.

Report L487 indicates climb rates at AE’s operating weight, should be in the range of 600-‐700 feet per

minute. However, Pellegreno reported routinely requiring 20 minutes to reach 1,000 feet, after takeoff.

L487 optimum initial cruise altitudes were 2,000-‐4,000 feet. Kelly Johnson modified the initial cruise

altitude to 8,000 feet.

In practice, climbing the heavy Electra to 8,000 feet, 10,000 feet, or higher, likely required 30-‐60 minutes

at high power settings of approximately 500-‐550 BHP and high fuel consumption ranging from 95-‐110

GPH (Pratt-‐Whitney).

AE’s Electra gross weight is important because the mission routinely operated at high gross weight.

Takeoff from Lae was at approximately 15,500 pounds, 47.6% above design maximum gross weight. The

Lae to Howland mission average gross weight was approximately 22.9% above design maximum gross

weight.

One concern was that if the Kelly Johnson flight tests were performed at significantly “lower-‐than-‐actual-‐

mission” aircraft weights, the resulting profile recommendations could result in AE experiencing less

climb rate, slower aircraft speed, and higher fuel consumption throughout the World Flight.

Our assessment is that Kelly Johnson’s data was accurate.

The empirical data from Kelly Johnson’s flight tests are very close to Pratt-‐Whitney engine data, and

likely resulted from either testing the Electra at actual operational weights, or from computational

corrections to test data, producing the three Telegrams recommending the following fuel consumption

planning data.

• 3 hours at 60 GPH for 180 gallons






This data agrees well with fuel consumption data we derived by calculations from Pratt-‐Whitney engine

data supplied by the Smithsonian Institution, and from flight handbooks for other aircraft using the same

engine as in AE’s Electra.

Kelly Johnson specified settings for 3-‐hour cruise segments, however, he did not specify takeoff, climb or

descent fuel consumption data.

Combining Pratt-‐Whitney engine data, with Kelly Johnson’s recommendations and data, offers a more

complete profile of fuel consumption.

• Takeoff using 10 gallons

• 1 hour climb using 110 gallons




• 8.5 hours at 38 GPH using 323 gallons

• 0.5 hours descent at 30 GPH (estimated) using 15 gallons

• Total 920 gallons required from takeoff to 1912 GMT

Fuel Consumption and Time Remaining From All Analyses

Below summarizes the solutions for mission fuel consumed, and fuel remaining upon arrival at where AE

thought Howland should be, at 1912 GMT.

• If AE began with 1080 gallons, and flew this Kelly Johnson profile (“adjusted” for takeoff, climb

and descent) requiring 920 gallons, the total fuel remaining would have been 160 gallons at

1912 GMT, or 4 hours endurance.

• Computer flight profile modeling of data largely from Kelly Johnson and L487 data, also indicate

the total fuel remaining would have been 160 gallons at 1912 GMT, or 4 hours endurance.

o While our Jeppesen software model results, in terms of fuel used, corroborate the Kelly

Johnson/L487 Report, our further analysis offers increased accuracy in this area.

• Swenson and Culick’s analysis concluded that AE had enough fuel for 20 hours 38 minutes total

mission time. Subtracting the known mission time of 19 hours 12 minutes, results in

approximately 1 hour 26 minutes remaining endurance.

o This represents 57.3 gallons remaining at 1912 GMT.

• Our research, using a specific flight profile segment analysis technique, results in a total mission

fuel burn of 957 gallons. Under the best circumstances AE should have arrived at time 1912 GMT

with 123 gallons, enough for 3 hours 04 minutes endurance.

o This figure could have been reduced due to malfunction of the Cambridge Fuel Analyzer

and increased fuel consumption en route due to cruise altitude choices, winds or other

factors.



“…Gas is Running Low…”

For the Oakland to Honolulu flight, AE planned to have 4 hours of fuel remaining, a “…good safety

margin…” by her own account. AE also planned on having enough fuel on the Honolulu to Howland

flight, 8 hours fuel remaining, to return to Honolulu from Howland in the event of an aborted landing

situation.

Below 4 hours fuel quantity, even were it planned, AE would likely consider this a low fuel quantity

situation, as she reported at 1912 GMT.

• With fuel remaining of 4 hours, per Kelly Johnson/L487, and software modeling solutions, it is

not likely that AE would have reported a low fuel condition.

• With fuel remaining of 1 hour 26 minutes, per Swenson and Culick, it is likely AE would have

reported a low fuel condition, but possibly with a sense of urgency, due to the extreme nature of

her fuel quantity, with just 57.6 total gallons remaining.

o Our analysis of 3 hours 04 minutes fuel remaining falls within the range for AE to report

a low fuel condition, but without a sense of urgency. This figure could have been reduced

due to malfunction of the Cambridge Fuel Analyzer and increased fuel consumption en

route due to cruise altitude choices, winds or other factors.

Engine Specific Fuel Consumption (SFC) Detail

Kelly Johnson’s third Telegram modifying World Flight operating parameters is important because

indications from direct evidence are that AE closely adhered to these recommendations for altitude, and

for mid-‐segment power setting, speed and fuel consumption, throughout the World Flight.

Unfortunately, AE made no reference to actual fuel burn, and drawing conclusions in this area requires

analysis from a broad spectrum of data.

Assembling various aircraft performance data elements from pre-‐mission preparations, and 30 days of

the World Flight, provides information on engine settings, speeds, altitudes, etc. These can be used to

assess BHP, from which specific fuel consumption (SFC) can be derived.

The engine’s specific fuel consumption (SFC) is an engineering parameter, defined as “pounds of fuel per

brake horsepower per hour.” Since this term is difficult to put into perspective, a more useful metric is

gallons per hour (GPH).

SFC can be directly converted to GPH, and related to miles per gallon, range, and endurance.

We examined Pratt-‐Whitney documents from the Smithsonian Institute for AE’s engines, Swenson and

Culick’s SFC calculations, and flight handbook engine operating data for nearly the same engine installed



in a North American T-‐6 single engine aircraft, as well as for the Lockheed 10A aircraft, in context with all

other performance data.

While the lack of Electra 10E-‐specific operating data hampered the investigation, we found that

published operating information also varies among sources. Examples include

• For takeoff, the Pratt-‐Whitney R-‐1340-‐S3H1 engine has a 5-‐minute time limit at that power

setting, per Pratt-‐Whitney documents.

• The L487 report specifies setting takeoff power for 1 minute, then directs a power reduction

“…as soon as it is safe…” (L487 p6). It does not define climb conditions.

• Swenson and Culick discusses a climb power setting of 420 brake horsepower (BHP). The source

of this specification is not provided.

• Pratt-‐Whitney specifies 550 BHP for climb, in engine data charts.

For cruise power, Swenson and Culick does not discuss power settings. L487 specifies for AE’s initial gross

weight, a cruise power setting must be 375-‐400 BHP.

The graph below is plotted from Pratt-‐Whitney engine data for AE’s engines. The GPH curve (parabola) is

relatively flat in the range of 250-‐400 BHP typically used for cruise flight, producing a linear relationship

of BHP and GPH.

Figure 12 -‐ From Pratt-‐Whitney Engine Data

BHP setting is important to a mission fuel analysis, because fuel consumption is directly proportional to

BHP and gross weight.

40.6 43.5 47.0

50.4 54.8

59.4 64.0

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

200 250 300 350 400 450

GPH

Lockh

eed Electra 10E

BHP

GPH SensiBvity to BHP

GPH



At initial heavy gross weights, higher BHP in the range of 375-‐400 BHP is required, while at lower gross

weights (achieved at approximately one third of the mission distance) power can be reduced to more

economical settings, such as 250 BHP, to maintain prescribed speeds and altitudes, and achieved desired

ranges.



The table below compares sources of fuel consumption data, with the associated effect on the mission

fuel used (Total Gallons Required).

Profile Segment

Kelly Johnson GPH

Kelly Johnson Fuel Used (gallons)

“Adjusted Kelly Johnson Fuel Used (gallons)

Pratt-‐Whitney GPH

Pratt-‐Whitney BHP

Time (hours)

Pratt-‐Whitney Fuel Used (gallons)

Takeoff N/A 10 0.08 (5 min)

10

Climb N/A 110 110.0 550 1 110 Cruise 60 180 180 61.8 390 3 190 Cruise 51 153 153 54.8 350 3 165 Cruise 43 129 129 40.6 250 3 122 Cruise 38 380 323 40.6 250 8.5 345 Descent N/A 15 (est.) N/A N/A 0.5 15 (est.) Total Gallons Required 842 920 19.08 957 Table 6 -‐ Engine Fuel Consumption

As corroboration, the P&W R-‐1340-‐AN-‐1 engine in the North American T-‐6 aircraft achieves its best long-‐

range cruise at 5,000-‐10,000 feet altitude, burning 22-‐23 GPH. For simplicity, we can double this value,

to approximate a representative cruise value for the twin-‐engine Electra of 44-‐46 GPH.

Differences among source data are relatively reasonable for the 1937 period

• AT-‐6 engine GPH data, doubled to approximate Electra fuel consumption, is within 10% of simple

(non-‐weighted) averages for Kelly Johnson and Pratt-‐Whitney data.

• Kelly Johnson and Pratt-‐Whitney GPH data are within 3% to 7%.

• L487 specifies initial cruise fuel consumption of 57 GPH

o Within 4%-‐8% of Pratt-‐Whitney data.

o Within 5%-‐11% of Kelly Johnson data.

• Kelly Johnson and L487 cruise fuel burn at 250 BHP is 39.2 GPH

o Within 4% of Pratt-‐Whitney’s published chart data.

o Two-‐thirds of the Lae to Howland mission was specified to be flown at 250 BHP, which

was also used by AE during the Natal to Dakar Atlantic Ocean crossing, earlier on the

World Flight.

Pratt-‐Whitney engine data examined, to date, is for standard conditions of pressure and temperature.

The Lae to Howland environmental conditions in temperature were warmer than sea level standard,

which increases fuel flow. Flying at high altitude, while not exceeding optimum altitude, has a small

positive effect on reducing fuel flow for AE’s engines.

These effects could account for differences between Pratt-‐Whitney engine data, and Kelly Johnson flight

test data.



MSI Analysis (Multi-Source Integration)

Despite the absence of specific Lockheed 10E Flight Manuals, flight tests, and variances in published

data, we can reach reasonable conclusions using all available resources.

After departing Lae with 1080 US gallons, and arriving in the Howland area at 1912 GMT, Fuel

Remaining values from Kelly Johnson, L487, and our specific analyses, are all among the 9 unique results

from Swenson and Culick’s interesting and comprehensive sensitivity analysis.

These 9 unique results are shown on the following graph. These serve as increasing confidence in

identifying reasonable values for fuel consumption, fuel remaining, endurance time after 1912 GMT, and

where the Electra could be located.

Figure 13 – Swenson and Culick conclusions (Average 21.37 hours. Standard Deviation 1.58 hours)

Conclusions for Fuel Consumption

The conclusions from this analysis include

• AE had sufficient fuel for the Lae to Howland flight under existing environmental conditions, for

Paths A, B and C, plus adequate reserves for a terminal area search.

• After 2013 GMT there were no further transmissions heard from NR 16020.

o Given AE’s communication history, this is uncharacteristic.

o AE transmissions are expected at 2030 GMT, 2045 GMT, and 2100 GMT.

o This supports a theory of a pre-‐fuel exhaustion water impact, possibly between 2013

GMT and 2100 GMT.

20.63 19.63 21.83

23.63 23.25 21.63 22.25

18.92 20.5

0

5

10

15

20

25

0 2 4 6 8 10

Mission

Hou

rs

Case Number

Swenson and Culick Fuel Endurance Time

Time



This may result from a CFIT event, or a mission fuel over-‐burn.

• The fuel consumption rates in GPH computed from Kelly Johnson, L487, and Pratt-‐Whitney

engine data, reasonably agree with empirical data from AE flight logs and position reports, in the

range of 250 BHP prescribed for mission cruise.

• A summation of discrete, mission segment analyses can produce a more accurate result in fuel

consumption, using BHP and SFC with all other data.

• Reaching Gardner Island, at approximately 400 statute miles distant, at 120 mph would require

3 hours 22 minutes, after 2013 GMT, or 4 hours 22 minutes after arriving at Howland Island at

1912 GMT.

o Only Case 4 and 5 in Swenson and Culick’s analysis enable this result.

Possible Impact Areas

At 1912 GMT the three basic fuel remaining scenarios are

• 1 hour 26 minutes

• 3 hours 04 minutes (and reductions due to possible failure of the Cambridge Fuel Analyzer)

• 4 hours 00 minutes

Position estimates result from search maneuvering and estimates of aircraft position in time.

Key points include

• At the Path C EON point, the aircraft flys west for 10sm, then east for 10sm, then east another

10sm. At that point, AE reported, “circling,” and embarks on flying the LOP as a magnetic

compass heading 337 degrees.

• The LOP is flown for 20 minutes, covering 40sm.

• A turn east then to a compass heading of 157 degrees, requires 6-‐7 minutes, where the aircraft

then searches southeast.

• This pattern is continued until reaching a 4-‐hour fuel exhaustion point.

Three key locations are added to the search area, corresponding to fuel remaining calculations, from

Swenson and Culick, Kelly Johnson/L487, and our analysis.

Key inferences from this analysis include

• It is realistic to expect further AE radio reports from 2030 GMT to 2100 GMT, or later.

• The aircraft would be located in the search grid at 2100 GMT.

• Of the three fuel remaining calculation scenarios

o The Kelly Johnson/L487 point is considered least likely.

o The Swenson and Culick point is considered possible.

o A point between our most optimistic calculation and the Swenson and Culick result is

considered the most likely of the fuel exhaustion scenarios, allowing the possibility of an



en route failure of the Cambridge Fuel Analyzer, slightly increased fuel consumption

rates, and reduced fuel remaining in the Howland Island area.



Search Considerations

If AE used fuel differently from this analysis, she likely used more fuel, not less fuel, resulting in fuel

exhaustion in less than 3 hours 04 minutes, and within the Search Grid.

Effects of Significant Lateral Deviation North of Path C

If the aircraft passed overhead Nauru Island, it would mean that navigation had either inadvertently

deviated 120nm in just three hours since flying over Nukumanu Island, or the course deviation was

intentional to facilitate sighting Nauru’s expected lights, and logging the last good navigation fix until

Howland Island.

An inadvertent deviation of this magnitude is very unlikely.

Intentionally passing overhead the island to establish a position is a reasonable intention. Unfortunately,

there is no evidence to support the theory.

If we suppose that it did occur, then the course to Howland Island from overhead Nauru Island converges

with the Path C track, terminating within a few miles northwest of the Path C End-‐of-‐Navigation point.

No matter how close to Nauru Island the Electra passed, at 1912 GMT on Path C it would be located

within the Search Grid, very near the Path C EON point.

From a position overhead Nauru Island, another possible course would parallel Path C to 1912 GMT.

This is considered unlikely, as it would indicate intentional navigation to a point other than Howland

Island, or a failure to correctly navigate to Howland Island.

Conclusion

The effects of reasonable lateral deviations place the aircraft in the existing Search Grid for scenarios of

wind and weather considered possible, or likely.



Appendix 2

Search Grids and Grid Coordinates







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