Weather Is the - AF

Weather Is the Issue

Weather Is the Issue

U N I T E D S T A T E S A I R F O R C E

M A G A Z I N E

MAY 1999

MAY 1999, VOL 55, NO 5AIR FORCE RECURRING PUBLICATION 91-1

THE ISSUE:

4 New-Age Weather Knowledge for the AircrewsThe ongoing reengineering of Air Force weather operations

7 Boomers and a Bad Radar“We soon found ourselves in moderate icing conditions,and the air was getting a little bumpy…”

8 Into the Eye of the StormAn “insider’s” view of Hurricane Georges

11 Lt Gen Gordon A. Blake Aircraft Save Award

U N I T E D S T A T E S A I R F O R C E

M A G A Z I N E

12 Figuring on FogExamining one of the most common—and danger-ous—weather hazards to flight

14 Thunderstorms—An Operational ViewSome advice on preparedness from a weather shop

16 Pilot Fatigue Manageable, But Remains Insidious ThreatUnderstanding how fatigue affects your perfor-mance is the first step in regaining your edge

21 Meeting a Microburst“We were lucky…conditions that day let us see the microburst and avoid it”

22 When Lightning StrikesAs the Ka-Boom!!! in your ears subsides…

26 There I Was…“The precipitation was so heavy and the noise was sogreat,we couldn’t hear each other over the intercom”

27 Altimeter Settings RevisitedHigh to low, look out below

28 Maintenance MattersPlanes, Trucks, and Automobiles…plus USN Crossfeed

30 The Final-Only ApproachCan an instrument pilot ever know too much about flying?

31 The Well Done AwardSMSgt David P. Sando

Cover photo by SSgt Billy W. Johnston

FSM

MAY 1999 ● FLYING SAFETY 3

GENERAL MICHAEL E. RYANChief of Staff, USAF

MAJ GEN FRANCIS C. GIDEON, JR.Chief of Safety, USAF

LT COL J. PAUL LANEChief, Safety Education and Media DivisionEditor-in-ChiefDSN 246-0922

JERRY ROODManaging EditorDSN 246-0950

CMSGT MIKE BAKERMaintenance/Technical EditorDSN 246-0972

DOROTHY SCHULEditorial AssistantDSN 246-1983

DAVE RIDERElectronic Design DirectorDSN 246-0932

MSGT PERRY J. HEIMERPhotojournalistDSN 246-0986

Web page address for the Air Force Safety Center: http://www-afsc.saia.af.mil

Then click on Safety Magazines.

Commercial Prefix (505) 846-XXXXE-Mail — [email protected]

24 hour fax: DSN 246-0931Commercial: 505-846-0931

DEPARTMENT OF THE AIR FORCE —THE CHIEF OF SAFETY, USAF

PURPOSE — Flying Safety is published monthly to pro-mote aircraft mishap prevention. Facts, testimony, andconclusions of aircraft mishaps printed herein may notbe construed as incriminating under Article 31 of theUniform Code of Military Justice. The contents of thismagazine are not directive and should not be con-strued as instructions, technical orders, or directivesunless so stated. SUBSCRIPTIONS — For sale by theSuperintendent of Documents, PO Box 371954,Pittsburgh PA 15250-7954; $25 CONUS, $31.25 foreignper year. REPRINTS — Air Force organizations mayreprint articles from Flying Safety without furtherauthorization. Non-Air Force organizations must advisethe Editor of the intended use of the material prior toreprinting. Such action will ensure complete accuracyof material amended in light of most recent develop-ments. DISTRIBUTION — One copy for each three aircrewmembers and one copy for each six direct aircrew sup-port and maintenance personnel.

POSTAL INFORMATION — Flying Safety (ISSN 00279-9308) is published monthly by HQ AFSC/SEMM, 9700“G” Avenue, S.E., Kirtland AFB NM 87117-5670.Periodicals postage paid at Albuquerque NM and addi-tional mailing offices. POSTMASTER: Send addresschanges to Flying Safety, 9700 “G” Avenue, S.E.,Kirtland AFB NM 87117-5670.

CONTRIBUTIONS — Contributions are welcome as arecomments and criticism. The Editor reserves the rightto make any editorial changes in manuscripts which hebelieves will improve the material without altering theintended meaning.

FSMStray Blue SheetCourtesy ASRS Callback, Jan 99

A corporate pilot reports one more bit of stray paper—a re-cent issue of CALLBACK—made an impression. Apparentlynot quite a big enough impression…

I was just reading in the last CALLBACK about low altimetersettings. I thought that could never happen to me. Well, guesswhat? [As we were climbing out] Center had cleared us to FL270.They asked our altitude, as they showed us high. Sure enough, ouraltimeter was set on 28.92. The previous crew had had a setting of28.96. I had not even looked at the first two numbers. We had someother distractions, but that is no excuse. Never say never.

The last two numbers of the altimeter setting were so closeit didn’t register with the reporter that the first two numberswere a problem—the 28 should have been a 29.

Not Good Form

The commuter crew was flying in VMC on an IFR flightplan, but both pilots were distracted from their flying andmonitoring duties by Customs forms that could have waiteduntil the flight had landed.

We were given a descent clearance to 14,000 feet. It was the FirstOfficer’s leg to fly, and I was filling out our crew declaration Cus-toms form. I noticed the First Officer was also filling out the Cus-toms form, so I occasionally looked up to monitor our flight situa-tion. The autopilot was descending initially, but had somehowdisengaged without us knowing why. The autopilot warning an-nouncing disengagement only occurs below 2,500 feet AGL. Be-cause our descent was shallow and we were filling out our Customsforms, no one noticed we had descended through our assigned alti-tude until we were 500 feet below it. It was a light traffic day…andno traffic was on TCAS II. Center didn’t mention the altitude de-viation. In the future, I will pay closer attention to monitoring theautopilot…and I will supervise my First Officer more closely dur-ing autoflight.

The captain filed this report to document the uncom-manded disengagement of the autopilot. However, automa-tion—the “magic”—is never a substitute for flying the air-craft. The reminder for all is that the crew’s first priorityshould always be on flying duties, including altitude call-outs, checklists, and traffic watch. Ground duties should besaved and performed on the ground. ■

4 FLYING SAFETY ● MAY 1999

We reportedhere lastyear (June

1998—Editor) on the end-to-end restructureof Air Force Weather. I’m back now to hap-pily report that the promised dramaticchanges are progressing forward positively.

Beginning in August 1996, we analyzedthe strengths and weaknesses of a variety ofoperational support processes. Our goal wasto learn and then leverage solutions fromeach in order to set a higher standard fortwenty-first century aviation weather sup-port to improve flying safety. We had to ex-amine how to increase the effectiveness ofour most important resource, our people,while simultaneously increasing their jobsatisfaction and reducing their burnout from

higher-than-ever demands on their time andskills. We also had to look at the processesthat generate and deliver weather informa-tion with an eye toward new technologiesthat can enable us to work smarter, better,and cheaper. Finally, we had to revamp aninfrastructure that served us well throughthe Cold War but had to change to supporttoday’s environment.

To understand our transformation, youhave to view weather operational support interms of two parts: (1) a “kitchen” that cre-ates and prepares fine-scale accurate weath-er products and (2) a weather “server” func-tion that provides mission forecast weathersupport to our operational customers.

Our weather operations exist in manyplaces where observations, pilot reports,and other data are recorded, assimilated, an-alyzed, fed into computer weather models,and scrutinized even more before being

BRIG GEN FRED P. LEWISDirector of Weather, HQ USAF

New-Age Weather Knowledge for the AircrewsThe Continuing Reengineering of Air ForceWeather

New-Age Weather Knowledge for the AircrewsThe Continuing Reengineering of Air ForceWeather

An icing graphic for the Bosnia region from AFWIN


This summer we

embark on a

single career

track for our en-

listed weather

technicians

(our

weather

operators ). All

of our new re-

cruits will go

from their tech-

nical training ini-

tial skills course

at Keesler AFB,

Mississippi,

to one of our

new Operational

Weather

Squadrons.

turned into operational products. The Oper-ational Weather Squadron (our weatherforecast “kitchen”) is where we will createthe fine-scale, highly accurate weather infor-mation that operational field units will usein supporting their customers.

This is also the part where the most pow-erful computer—the human brain—plays akey role in blending the science with the art.The training and experience of the people inthis process are paramount to on-target op-erational weather support. This part is nor-mally far less visible to our customers, but isa crucial ingredient in our ability to providefine-scale, accurate, and relevant weathersupport. This information base is also key tohelping the aviation community with saferflight operations.

The weather “server” briefing function iswhere our weather people provide the in-formation to those who need it. Weatherforecasting, like many disciplines, has verymuch been swept into the information age.Nonetheless, we will continue to invest inhighly trained weather people for this partof the process so they can transfer theirweather knowledge into the operations.While we will apply more “virtual” serviceswhere it makes sense, we still believe thatweather people who know operations andthe operator who knows the weather remainthe keys to mission success and safer flyingconditions. Our weather people are ready toprovide on-target weather information any-where, anytime, and our reengineering ef-forts are designed to improve their abilitiesto do just that!

Many commercial enterprises that “serve”weather information are able to do so withlittle investment in their own “kitchen” asthey leverage the materials they need frompublic sources. As part of reengineering, AirForce Weather has also been aggressive atleveraging capabilities and informationfrom other sources to reduce our operatingcosts while improving accuracy. We areworking with the Navy, National WeatherService, and other agencies to build a na-tional capability. However, as part of the na-tional team, we are also a part of the “publicsource” of weather information and willcontinue to play a key role by sharing ourinformation with these same agencies.

As we mentioned in last year’s article, ourbusiness strategy is one of simplifying,streamlining, and leveraging more into our“kitchen” while putting fewer, but more ex-perienced and more mission-focused peoplein the information-delivery role. This new

approach directly supports the Expedi-tionary Aerospace Force (EAF) concept and,in fact, the EAF will allow us to provideeven better operational weather support.You, the operators and aircrews, are startingto see these changes, but there are more andbetter things to come. Here’s a quick pre-view of where we’re headed:

• People. This summer we embark on asingle career track for our enlisted weathertechnicians (our “weather operators”). Allof our new recruits will go from their tech-nical training initial skills course at KeeslerAFB, Mississippi, to one of our new Opera-tional Weather Squadrons. These squadronsserve as regional, reach-back hubs (ourweather forecast “kitchen”) to accumulatemeteorological knowledge for specific geo-graphical areas at finer scales than we’vedone in the past. They then provide the in-formation to operational weather units intheir area via reach-back and common-usercommunications. These hubs will create theaerodrome forecasts and constantly watchweather threats within their assigned re-gions.

Significantly, these hubs will also serve ason-the-job training (OJT) “factories”) wherewe place our least experienced people withour most experienced to produce highlytrained people to go to front-line field units(our base weather stations). We’re transi-tioning the base weather station of the pastinto a leaner mission-aligned team (theweather “servers”). These new weatherunits will contain only experienced people.

Further, we’ve simultaneously offloadedthe basic weather OJT burden from the baseunits and have turned them into mission-aligned teams. These mission-aligned teamswill focus more on the impacts of the weath-er. They will work more closely with opera-tors, even right in the operational units inmany cases, to optimize aviation supportand help generate safer flight operations.

• Processes. We want to deliver weatherinformation using the same processes inboth peace and war. The information deliv-ery style you’ve seen in contingencies ismore of what you’ll see everywhere now.You’ll see more mass briefings, more up-dates within individual flying squadrons,and more direct interactions with the Super-visor of Flying—more up close and person-al weather support!

You may see more automation added inour weather observing capability, but wemust continue augmenting observingequipment with a person-in-the-loop dur-

continued on next page


ing flight ops. As we move forward, thisperson-in-the-loop will now be a forecastertaking observations—a “weather opera-tor”—not an observer. This opens manypossibilities for improving mission-criticalweather support when weather is rapidlychanging.

• Infrastructure. We’re using our hubsand centralized facilities to concentrate ourexpertise and more complex equipment atfewer sites. These sites will provide very ac-curate weather information to field units intheir region while at the same time lowering

our equipment costs. You’ll see our fieldunits begin to use more off-the-shelf com-puters and use web-technologies to collectand deliver information. We’re also fieldingbetter means of communications, such ascommercial VSAT technologies and al-phanumeric pagers, to get the informationmoved faster, better, and cheaper to the peo-ple who need it most.

We believe our changes are on target toimprove weather support for operationsand this has and will remain the main goal!We took note during our reengineeringstudies that in the face of tough fiscal pres-sures, major airlines are maintaining theirown meteorology departments to work withtheir flight dispatchers and airfield man-agers. Many airlines found it was good busi-ness to invest in the infrastructure needed toprovide the weather information their air-crews use to plan and fly on because it gavethem a competitive advantage.

Focused weather information also givesthe military an advantage—the ability to“anticipate and exploit” the weather in thebattle space to provide another edge overany adversary. Our new capabilities also letus help the Air Force team better prepareand protect our war-fighting resources fromsevere weather—contributing to overallforce readiness and safer operations.

As our Air Force Weather reengineeringcontinues, we’re already seeing a leanerweather organization emerging that is de-voted to providing the best mission-scaleaviation weather information in the world.Information that will provide our aircrewswith the weather knowledge needed to con-duct and sustain safer, on-target military op-erations anywhere in the world, anytime.This whole effort is designed with you—thewarfighter, the operator, and the trainer—inmind. I encourage your help in continuingto make our vision a reality. If you wouldlike to provide us with your thoughts onhow we can continue to become even better,p l e a s e f e e l f r e e t o c o n t a c t m e a [email protected].

“Weather on Target for saferoperations!”

Two sequential graphics from AFWIN covering a threeday span tracking an easterly moving weather pattern.

No one plans to fly into a thunderstorm. I’d beenthrough all the weather lectures that stressavoiding turbulence, icing, and lightning

around convective activity, but the point wasn’t trulydriven home until I experienced it first hand.

The day was going to be a long one. I was flying theP-3C on a round-robin from NAS Moffett Field, Califor-nia, to Wright-Patterson AFB, Ohio, then to NAS Glen-view, Illinois, and back to Moffett. In all, it would beabout a 16-hour day if we had no delays.

The weather brief at Moffett made it clear therewould be some interesting flying in the Midwest wherewe were headed. A strong cold front was making itsway through the Great Lakes states, creating somepowerful thunderstorms. The weather was clear andcalm in California, as it is almost every day in the sum-mer. The weather remained clear until we reached theMississippi River on our way to Wright-Pat. We weresoon requesting deviations from track to avoid theweather, and ATC gave us radar vectors to avoid a lineof cells between us and our destination. Everythingwent smoothly, and we made it safely into Wright-Pat.

On the ground, my second pilot and I went intoweather for a thorough update on what to expect onour way to Glenview. The line was forecast to be pastChicago by the time we arrived, but first we wouldhave to circumnavigate a group of cells crossing Indi-ana. The weather at Wright-Pat wasn’t exactly CAVU(clear and visibility unlimited), either. The sky hadgrown dark, and cells were poised just northwest of thefield. We decided to jump back into the plane and tryto make our way before the cells reached the field.

As we taxied, I talked to Metro for an update. Thecells were about 3 miles west of the field, but cloudshad darkened the sky, and we needed to decidewhether to take off. The flight engineer and the secondpilot said they wanted to wait out the storm. However,the third pilot and I were sure we could safely take offto the south and then navigate our way around thecells visually, using the aircraft’s radar and taking radarvectors from Center.

The decision was ultimately mine, and I decided togo. As it turned out, we were able to navigate our wayaround the storms in the vicinity of Wright-PattersonAFB and head toward Glenview.

The first 25 minutes of the leg were uneventful. Wevisually navigated our way around the cells, requestingdeviations to avoid the weather. We also checked withthe radar operator in the tube of the aircraft to confirmthe headings. At times, his calls of the clouds ahead didnot seem to jibe with what we saw, but with clouds allaround, I assumed he was looking at another cloud. Ihad no reason to think we might have a problem withour radar. Unfortunately, we did.

The radar azimuth was no longer locked into align-

ment, and what the radar operator saw on the screenas being straight ahead was actually at the 8 o’clockposition. The radar was 120 degrees out of slew!

Flying at FL240, we soon entered some thin cloudssurrounding the larger cell. I could no longer dependon visual means to circumnavigate the boomers. Sowhat did I put my faith in for storm avoidance? Aradar system that was out to lunch.

“Sensor Three,” I called the P-3 radar operator,“what’s the best heading to avoid these cells upahead?”

“It looks good straight ahead, sir. You should be outof this stuff in about 3 miles.”

It sounded good to me, so I continued ahead. But theweather did not improve. We soon found ourselves inmoderate icing conditions, and the air was getting a lit-tle bumpy. The third pilot did an excellent job of flyingthe aircraft while I tried to find our way out of themess.

“Three, Flight, are we going to break out of this stuffsoon? It’s getting kind of ugly up here. Let’s set condi-tions 5, guys.”

“Flight, Three, you should be breaking out of thisstuff any second.”

According to his radar scope, we should have brokenout, but what he saw as straight ahead was actually aclear signal caused by the radar blanket (which pro-tects the inside of the aircraft from the radar energy). Itwas now becoming apparent this radar was having atough day and couldn’t be trusted. By this time, the ic-ing was heavy, and communication with ATC was al-most impossible because of static caused by the icing.We were in moderate turbulence, and we could seelightning. What scared me the most, though, was that Ihad no idea what lay ahead. Stories of aircraft drop-ping 20,000 feet and suffering Class A damage instorms ran through my head. Was this to be our fate?

Fortunately, it was not. I finally established commwith Center and asked for radar vectors out of the cell.At first, they reported they weren’t painting us onradar, which didn’t make me feel real good. But theypicked us up again and told us to continue on course.In a minute or two, we were out of the bad weatherand continued on to Glenview without incident. Wespent the night at Glenview while we tried to repairthe radar and, more importantly, repair our nerves.

The aircraft made it through with only some chippedpaint on the nose radome and the leading edges of thewings. It could have been a whole lot worse.

The P-3C’s radar isn’t designed for weather avoid-ance, but many radar operators have learned to use thesystem to give the flight station a good heads-up onthe weather ahead. This breeds a certain level of falseconfidence that we can depend on the radar to bail usout of a bad situation. In my case, the radar was moreof a detriment than a help. I think the entire crewgained respect for the danger of a storm cell, and youcan bet I’ll keep a safe distance in the future.

LT MARK E. SCHIMPFCourtesy Approach, Nov 93

Boomers and a Bad RadarBoomers and a Bad Radar


Powerful winds slammed into theWC-130. Sheets of rain poundedagainst the cockpit windows—turning the world ahead into asolid wall of gray. Inside, the crewstruggled to read the instru-ments, blurred at times by the150+-mph winds that buffetedthe aircraft. In the back, a crew-man prepared to release a drop-sonde into the hurricane whileABC reporter Rebecca Chase gotready to go on camera as theplane penetrated the eye.

Suddenly, an air pocket causedthe plane to momentarily drop—anything that wasn’t securedwent airborne. The crew and pas-sengers snugged up their seatbelts and held on. The 53d Weath-er Reconnaissance Squadron’s(WRS) “Hurricane Hunters” hadstepped into the center of thering, and Hurricane Georges waspacking a punch.


MSGT MICHELE L. RIVERA403 WG/PA (AFRC)

Powerful winds slammed into theWC-130. Sheets of rain poundedagainst the cockpit windows—turning the world ahead into asolid wall of gray. Inside, the crewstruggled to read the instru-ments, blurred at times by the150+-mph winds that buffetedthe aircraft. In the back, a crew-man prepared to release a drop-sonde into the hurricane whileABC reporter Rebecca Chase gotready to go on camera as theplane penetrated the eye.

Suddenly, an air pocket causedthe plane to momentarily drop—anything that wasn’t securedwent airborne. The crew and pas-sengers snugged up their seatbelts and held on. The 53d Weath-er Reconnaissance Squadron’s(WRS) “Hurricane Hunters” hadstepped into the center of thering, and Hurricane Georges waspacking a punch.

For 9 daysthe 53 WRS hadtracked the

powerful storm from the western Atlantic,through the Caribbean, and into the Gulf ofMexico. It was all too obvious that Georgeswas bearing down on Biloxi. Now it was theHurricane Hunters and their families’ turnto be the “hunted.” When the storm roaredashore on 28 September 1998, somecrewmembers took to the skies with mixedfeelings.

“Before we left, we knew there was a goodprobability of it hitting here. I looked aroundthe house and wondered if there was any-thing I wanted to keep,” said Capt ArnoldMichels, a 53 WRS aerial reconnaissanceweather officer. “But I didn’t take anythingwith me—it was too hard to carry every-thing.”

But that didn’t stop Michels from wonder-ing what he would find when he returned.“When you deploy in a case like this, there isa possibility that you will come back to totalhavoc,” he said.

One thing Michels didn’t have to worryabout was leaving family members behindto have to cope for themselves. “I’m single,but a couple of crewmembers certainly wereconcerned. It was tough for them to go flythe mission, knowing their families weredown there.”

MSgt Roy Cloud, a flight engineer, wasone of those who had to leave family behindin Mississippi.

“That’s the bad part of the job and the rea-son we like to get back as soon as we can,”said Cloud. “We’re out there doing a hu-manitarian mission and trying to help savelives, but at the same time we’re worriedabout the families we’re leaving behindwhile we’re flying.”

Had Hurricane Georges hit the Gulf Coastat its peak, the crewmembers would havehad even more to worry about. On 19 Sep-tember, during the first mission flown, mete-orologists on board the WC-130 aircraftfound winds as high as 148 mph and pres-sure dropping rapidly from 949 to 938 mil-libars. This made Georges a strong Category4 storm at the time.

The well-defined eye seen on satellite im-ages was even more impressive when seenup close from the inside of the eye. The wallof clouds lining the eye creates what crewscall the “stadium” effect.

“This stadium effect is so good you caneven count the bleachers,” said Maj DallasEnglehart, one of two pilots steering the air-craft carefully through the storm. “Visually,


continued on next page All photographs by MSgt Michele L. Rivera

SSgt Kari Kennedy preprograms trackinginformation prior to releasing a dropsondeinto the hurricane.

The “stadium effect” created by theclouds lining the eye of HurricaneGeorges was one of the most impres-sive ever seen by the HurricaneHunters.


predictions—temperature, pressure, humidity, andwind speed and direction.

Each time the aircraft passes through the eye of thestorm, the dropsonde systems operator releases a cylin-drical dropsonde from the aircraft that measures thesame data as the on-board sensors as it descends to thesurface of the ocean. Information gathered from thedropsonde is particularly valuable in determining thecentral pressure, and thus the strength, of the storm. TheNHC combines that data with information gatheredfrom the outer edges of the storm to determine where topost hurricane warnings.

“The National Hurricane Center has determined thatour data helps increase the accuracy of their forecasts byat least 25 percent,” said Maj Doug Lipscombe, an aerialreconnaissance weather officer. “Also consider the factthat it costs about $1 million per mile of coastline everytime an evacuation is ordered. If our data can help re-duce the overall warning area, we help the Americantaxpayers save money every time we fly a storm.

“Our motto is Pro Bono Publico—for the public good.That’s the whole reason we’re out there—to help savelives and money.”

Readers interested in obtaining more information on theHurricane Hunters’ mission can visit their home page athttp://www.hurricanehunters.com/welcome. htm. Clickingon “Cyberflight Into the Eye” will allow readers to join thecrew of Teal 41 as they fly a weather reconnaissance missioninto Hurricane Opal.

Editor’s Note: MSgt Michele Rivera is an Air Reserve Techni-cian assigned to the 403d Wing Public Affairs Office atKeesler AFB, Mississippi. She has served with the unit for 10years and has flown on numerous hurricane reconnaissanceflights assisting media in covering the Hurricane Hunter’s mis-sion.

this is the storm of the century,” added dropsonde sys-tems operator CMSgt Mike Scaffidi.

As the week progressed, the Hurricane Hunters flew17 missions into Georges, providing the National Hurri-cane Center in Miami with vital information around theclock on the storm—information the center uses to pre-dict the storm’s path.

The group of reservists is called any time a tropicalsystem threatens land in the Western Hemisphere. Witha fleet of 10 WC-130s, they are responsible for trackingstorms in the Atlantic, Caribbean, Gulf of Mexico, andeastern Pacific. Depending on the severity of the hurri-cane season, which lasts from June through November,it’s possible to have crews flying reconnaissance in twoor three systems at a time.

Storm reconnaissance frequently starts as a low-levelhunt, below 1,000 feet, looking for the pressure andwind readings that would categorize the system as atropical storm. As wind speed and turbulence increase,so does the altitude at which the Hurricane Huntersfly—from 1,000 to 5,000 feet in a tropical storm, to 10,000feet in a fully developed hurricane. They fly at the dif-ferent levels for two reasons: to provide the NationalHurricane Center (NHC) with data at prescribed pres-sure altitudes; and for safety. In a fully developed hurri-cane, 10,000 feet allows the aircraft to adjust for pressurechanges and the sudden updrafts and downdrafts thatfrequently occur in the thunderstorms that make uphurricanes.

A typical mission can last up to 12 hours, dependingon the time it takes to reach the storm. Each mission con-sists of crossing the storm four times in a figure-X pat-tern, starting 105 miles from the center, crossing the eye,then proceeding 105 miles straight out the other side. Asthe aircraft crosses the four different quadrants, on-board sensors gather data the NHC needs to make its

Maj Dan Darbe (left) computes windspeedon the surface of the water.

Dropsonde operator TSgt Scott Denham(right) assists the weather officer by takingsurface observations.

CMSgt Mike Scaffidi (above) has just fin-ished charging the dropsonde battery inpreparation for releasing the dropsonde intoHurricane Georges.


SSgt Timothy (Shane) Watts, (NATCF, Lee RadarController), 57th Operations Support Squadron, NellisAFB, Nevada. After observing a 7700 beacon code, SSgt Wattscoordinated with Salt Lake Center to identify the aircraft andimmediately get the pilot on his frequency. After the civilian pilotchecked in with SSgt Watts, the aircraft went into a tailspin dueto severe turbulence. Once the pilot regained control of the air-craft, SSgt Watts calmed him and issued flight instructions thatwould ensure the aircraft remained above the mountainous ter-rain. With the aircraft encountering severe winds, he providedthe pilot with precise radar vectors towards the most suitable air-port. When the pilot reported the airport in sight, SSgt Watts gavehim landing information, instructed him how to operate the air-port lighting system, and then switched him to unicom. SSgtWatts’ personal experience as a pilot and his knowledge of theNellis Range Complex allowed him to prevent a possible disas-trous situation for a disoriented pilot and his wife.

TSgt Stephen M. Browning, (Tower), 314th OperationsSupport Squadron, Little Rock AFB, Arkansas. Just afterbeing relieved from his position, TSgt Browning noticed a blueAir Force vehicle and a forklift proceeding onto a taxiway. Thevehicles didn’t appear to be slowing down as they approachedthe active runway. Due to the busy tower pattern and abundanceof taxiing aircraft, the local and ground controllers were focusedon controlling their own traffic and apparently didn’t notice theunauthorized vehicles. TSgt Browning alerted the tower crew ofthe imminent incursion, and the local controller immediatelyactivated the red light on an aircraft that was over the numbers.The aircraft was in the flare, but the GCA controller was able tosend the aircraft around just as the vehicles entered the runway.TSgt Browning likely saved the lives of several personnel and $20million in Air Force assets due to his situational awareness andattention to the local flying environment.

SSgt William F. Conley, (Tower, Watch Supervisor), 14thOperations Support Squadron, Columbus AFB,Mississippi. SSgt Conley noticed a T-37 in the RSU pattern onshort final descending to land with no gear. He immediatelybrought attention to its condition, and the ground controllerkeyed up Guard frequency to send the aircraft around. SSgtConley’s aggressive actions and attention to detail prevented thepossible loss of two Air Force personnel and a valuable Air Forcetrainer aircraft.

LT GEN GORDON A. BLAKE

AIRCRAFT SAVE AWARD4TH QUARTER, CY98

Everyoneis familiar with thew e a t h e r — r a i n ,

snow, clouds, warm and cold fronts, andwind. For the pilot who flies in the “weath-er factory,” the changing conditions aloft areextremely important. Wind movement maycarry the plane off course, rain may freezeon the wings, strong vertical currents maytoss the aircraft around, and clouds or fogmay cover the ground.

Fog is not only one of the most commonweather hazards, it also is among the moredangerous because it’s encountered duringtakeoff and landing. The basic difference be-tween it and a low cloud is that the cloudbases must be at least 50 feet above theground.

Fog can be defined as a condition of poorvisibility at the ground due to suspendedwater droplets or ice particles. It generallyreduces visibility to less than 3 miles and, inmany cases, to zero. Conditions most favor-able to the formation of fog are light surfacewinds, high relative humidities, and anabundance of condensation nuclei. Lightwinds tend to thicken fog but, as windspeeds increase, depending upon the stabil-ity and type of fog, the fog either dissipatesor lifts to become low stratus clouds. Allfogs and low stratus are classified as airmass or frontal.

Air Mass FogsAir mass fogs are produced principally by

the cooling of moist air until it’s saturated.Cooling may be produced by contact cool-ing or by radiation. There are several typesof air mass fogs.

Advection fog is produced by advection(movement) of air of different propertiesover a surface that may be colder or warmerthan the air moving in.

Monsoon fog is produced by warm, moistair blowing from land onto relatively coolwater. It depends upon the temperature con-trast between land and sea and often occursin late spring and early summer. It’s foundchiefly over water, but since it forms close toshore, the afternoon sea breeze may bring itinland. It’s a persistent fog and may last forseveral days.

Sea fog is produced by air flowing fromover a relatively warm ocean surface to overanother, colder, surface. It may be found inany season, but it’s most common duringthe spring. Sea fog is common around theNewfoundland Banks where the warm GulfStream meets cold northern coastal waters.

There is a similar region off the easterncoast of Asia involving the Japanese Cur-rent. Rotating clockwise around the north-ern Pacific, it moves warm water northwardalong the Asian coast before moving coldwater from the Arctic southward along thewestern coast of North America.

Most advection fogs are produced by themovement of warm air onto a cold surface.But fog can also form if the condition is re-versed. This fog usually occurs on bodies ofwater in the fall and is sometimes called“autumn steam mists.” In the Arctic regionit’s known as “Arctic sea smoke.”

Up-slope fog: If an east wind carries suffi-ciently moist air across the Great Plains, itwill be forced skyward by the rising terrainand will be cooled approximately at the adi-abatic lapse rate. This is the rate at which theatmospheric temperature cools as altitudeincreases. The average change per 1,000 feetis 2°C. Since the air cools as it moves up theslope, it eventually reaches saturation.

In a radiation fog, the cooling of moist airto the point of condensation takes place byradiation; the air above it is cooled by con-tact with the ground. Fog that is of a localrather than a widespread nature forms inlow places, since elevated locations spillrather than collect cold air.

Ground fog is generally shallow anddoesn’t totally obscure the sky; the moonand brighter stars are visible through it.Since the fog is formed by the conduction of


A recent analysis

of 761 fatal

general aviation

mishaps in the

U.S. indicated

fog ranked fourth

among the 10

most frequently

cited causes/fac-

tors. It was deter-

mined to have

been a

cause/factor in

112 (14.72

percent) of

the fatal

mishaps

studied.

ROBERT I. STANFIELDBusiness Aviation Safety Journal, Vol 10, 1995

Figuring on

A serious takeoff and landing hazard

USAF Photo by MSgt Perry J. Heimer

Fog is not only

one of the most

common weath-

er hazards, it

also is among

the more dan-

gerous because

it s

encountered

during takeoff

and landing.

The basic

difference

between it and

a low cloud is

that the cloud

bases must be

at least 50 feet

above the

ground.

heat from the air to the ground, the depth towhich the fog can form under calm condi-tions is dictated by the vertical distancethrough which conduction cooling can ex-tend—3 to 4 feet in depth under ordinarycircumstances. If there is a slight amount ofturbulence, ground fog can be much thickerbecause it stirs the saturated air a bit.

Unless the formation is very deep and so-lar heating is slow, ground fog usually dissi-pates shortly after sunrise. Fogs of this typeare found in the central and western UnitedStates, but not usually in the eastern sec-tions. This type also forms frequently inwestern Europe.

Frontal FogsAs a rule, frontal fogs are of limited extent,

compared to air mass fogs, and are depen-dent upon phenomena associated withfronts.

Prefrontal warm front fog is found in thecold air ahead of a warm front where pre-cipitation is taking place. The region of pre-cipitation becomes saturated with moisture,and any cooling of the air is sufficient to pro-duce a fog.

The following factors favor formation ofthis fog:

• Cold ground.• High moisture content of cold air.• Winds in cold air that have an up-slope

component over the ground.• Snow-covered ground.

This fog is common in the eastern U.S., es-pecially during winter.

Prefrontal cold front fog is formed if acold front advances against a mountainslope. The air in front is pushed to altitudesby the cold air until fog formation in thewarmer air results.

Forecasting fog is difficult, and only a fewgeneral rules can be formulated. The forma-tion of fog depends on the occurrence ofconditions described and, therefore, de-pends upon the forecasting of the generalweather features. Here are the fog-favorablefactors that should be considered in aweather briefing:

1. Type of air mass (moist in lower levels)2. Character of locality (up-slope motion)3. Season of the year (cold ground surface)4. Path the air mass has followed (flowing

over colder surfaces)5. Wind velocity (low but not calm)6. Dew point (at or near air temperature)7. Radiation conditions (ground surface)8. Moisture content aloft if available (dry

air aloft)The dissipation of fog is assumed to be

due to heating from below caused by sun-light that filters through the fog or stratuslayer. The time after sunrise necessary todissipate fog is assumed to be longer thegreater the thickness of the cloud. Also, thislength of time is assumed to be longer thegreater the height of the inversion.

HazeHaze is generated when the dust and/or

salt particles normally dispersed in the at-mosphere are trapped and concentrated intoa stable atmospheric layer.

Most pilots have flown through haze inwhich distant objects appear to be veiled inpale blue, if they are dark, and yellow if theyare light. The intensity of haze increases asthe stability of the air increases. On occa-sion, surface-based haze layers may extendto altitudes of up to 15,000 feet.

Haze layers are frequently associated withhigh-level inversions because the air is sta-ble, and the top of the haze layer is usuallylocated near the top of the inversion. Whileair-to-air visibility is good above the inver-sion, air-to-ground visibility in and above ahaze layer, however, can be practically nil.At times, visibility is good straight downbut practically nonexistent horizontally.

The greatest restriction to visibility in hazeoccurs when looking into the sun. Here, thevisibility most often is zero, making it haz-ardous to land an aircraft into the sun whenhaze conditions exist.

SmokeUsually concentrated on the downwind

side of industrial areas, smoke normally re-stricts visibility when it’s trapped beneathan inversion. The surface, slant, and hori-zontal visibilities while flying in it are simi-lar to those in haze.

Smoke generated by forest fires is fre-quently transported over great distances athigh levels. In such cases, pilots may en-counter very poor horizontal and slantrange visibilities in dense smoke at flight al-titudes, although the lower levels are free ofsmoke.

Since smoke particles are nuclei uponwhich water vapor condenses, smoke andfog often occur together in industrial areas,resulting in “smog.”

Fog and other natural restrictions to visi-bility aren’t just common weather hazards—they can be deadly.


Editor’s Note: Permission to reprint this article fromthe Business Aviation Safety Journal was providedcourtesy of the Flight Safety Foundation.

The severethunderstormseason has re-

turned, and now’s as good a time as any totalk about how you can prepare to “weath-er” it safely.

Aviators often see thunderstorms in thecentral United States reach 60,000 to 65,000feet in height during the summer months,with average heights of around 40,000 feetmost of the year. These heights normallymean rethinking an intended route to avoidthe thunderstorms (protecting both pilotand aircraft from the effects of hail, light-ning, turbulence, etc.) or postponing theflight altogether.

When assigned to, or visiting, an airfieldpoleward of 48° north latitude, most severethunderstorms rarely exceed 35,000 feet,with the average height of most storms top-ping out at 20,000 to 25,000 feet. This ex-plains why aviators in northerly latitudesoften fly regardless of weather forecasts ofsevere thunderstorms along their route offlight. To understand why this is true re-quires a short review about the atmosphere.

The sun heats the atmosphere more at theequator, producing a thicker amount of at-mosphere than at the poles. A rule-of-thumbused by many weather folks says to subtractabout 2,000 feet from the central US maxi-mum cloud tops for every degree polewardof 35° north latitude. Thus, the farther northone flies the greater the possibility of flying

MR. GARY WICKLUNDSSGT BRIAN McDONALDSRA LANCE FISCHER377 ABW/OTWKirtland AFB, New Mexico

over most thunderstorms without incurringtheir wrath.

When the local base weather station hasevaluated all available information and de-termined the potential for severe weather,they issue a watch, a warning, or an adviso-ry, and notify key installation agencies(command post, wing operations center,etc.). This starts the process which initiatesprotective measures to ensure the safety ofpersonnel, property, and aircraft. Remem-ber: The base weather station forecasts for a5-nautical-mile radius. This may make aweather event, specifically severe weather,an uncertainty and increase the rate of falsealarms.

The “close—but no cigar” cliche best de-scribes what can happen when storms passeither side of a base without any direct im-pact. Regardless of the result, reacting toweather watches, warnings, and advisoriesshould remain the same time after time—take appropriate action now! Even whenbudget considerations might play a role inthe decision process, please do not deviatefrom the published plan of action.

For example, placing protective coveringsover sensitive components of a B-2 may cost$15,000 in extra manpower for each adviso-ry or warning issued. But weigh that costagainst one lost (or severely damaged) B-2,F-16, or C-141 by taking no action, and theargument becomes moot.

The Threats1. Wind gusts greater than 50 knots. Se-

vere thunderstorms frequently producevery strong gusts which are often referred to



as gust fronts, outflow boundaries, ordown/microbursts. Regardless, a trash con-tainer can do considerable damage to air-craft or buildings. Even cargo pallets havebeen known to leap tall perimeter fences. It’simportant to remove items that could be-come damaging—or deadly—missiles.

2. Hail greater than 3/4 inch. Personal in-jury and structural damage can, and oftendo, occur. Ensure people have sufficienttime to find shelter and that they stay clearof windows which could shatter and injurethem.

3. Lightning. This brilliant display of elec-trical energy strikes the earth about 200times every second. It kills, on average inthe United States, more than 100 people ayear and injures nearly 250 others. Whenlightning is a threat, people should seekshelter immediately, but NOT UNDERTREES! Please remember: Lightning canstrike the ground while the storm producingthe strike may be more than 5 miles away.

4. Flash flooding. Watch out for and avoidareas prone to flash flooding. Flood watersoften hide washed-out roads and bridgesand quickly increase in depth. Water 1 footdeep that is pushing against the side of a carcan make a 2-ton vehicle weigh less than 1.5tons. Water 2 feet deep often causes vehiclesto take unexpected and often deadly sidetrips down arroyos, canyons, ditches, etc.

5. Tornadoes. A tornado is one of the mostdevastating weapons in Mother Nature’s ar-senal. Tornadoes have occurred nearlyeverywhere on earth, making everyone, tosome degree, vulnerable. In the UnitedStates, the National Weather Service pro-

vides advance warning through the use ofTornado Watch Areas. These are typicallybroadcast on The Weather Channel, localtelevision and radio stations, and NOAAWeather Radio. If caught out in the openwhen a tornado strikes, find a ditch or otherlow-lying area. Lay face down, and don’tmove until the tornado has passed. NEVERREMAIN IN A VEHICLE.

What Can You Do to Prepare?A good first step comes with safety brief-

ings. Invite a weather person to conduct aweather safety briefing prior to the start ofthe severe season in your area to remindeveryone of severe weather signs and haz-ards.

Next, military installations make exten-sive use of various methods to notify per-sonnel of severe weather, such as tele-phones, public address systems, closedcircuit television, mobile radios, and webpages on the Internet. The key here is every-one needs to know what to do and how to respondwhen notified.

When threatening weather conditions ap-pear, do your part, whether it’s securing air-craft, removing loose objects from aroundbuildings, or simply ensuring all doors andwindows are closed. You are protectingyourself, your coworkers, and valuableproperty.

Finally, practicing what to do in the eventof severe weather is a great way to preparefor the real thing. Apply those lessonslearned from base/unit disaster prepared-ness exercises, and you’ll be ready whenMother Nature strikes.



“Pilot fatigueis a ma-jor safe-

ty concern in long-haul flying,” wrote DavidF. Dinges, Ph.D., and R. Curtis Graeber,Ph.D., in a paper presented at a Flight Safe-ty Foundation (FSF) workshop. “Althoughtoday’s automated flight systems preventthe sleeping pilot from losing control of theaircraft, the less extreme effects of fatiguecan seriously jeopardize flight safety.”

They went on to point out “Each month[the U.S. National Aeronautics and SpaceAdministration] Aviation Safety ReportingSystem (ASRS) receives reports from long-haul flightcrews describing how fatigue andsleep loss have contributed to major opera-tional errors such as altitude busts, track de-viations, landing without clearance, landingon the incorrect runway, and improper fuelcalculations. Such reports are not surprisingto any pilot who has flown all night over theocean while trying to stay awake and alert

STANLEY R. MOHLER, M.D.Wright State University School of MedicineDayton, OhioCourtesy Flight Safety FoundationHuman Factors & Aviation MedicineJanuary-February 1998

Pilot Fatigue Manageable, But Remains Insidious Threat

in the dim light and constant hum of thelong-haul cockpit. The problem worsensduring trips as the effects of jet lag and sleeploss begin to accumulate.”

A pilot’s duties in the cockpit require care,vigilance, and physical and mental well-be-ing. Cockpit noise, vibration, long flights, ir-regular work schedules, or too little sleepcan result in fatigue, which can compromisea pilot’s performance.

The management of human fatigue inflight operations is the primary responsibili-ty of the pilot, but responsibility also falls onthe operator and on government authorities.Air carriers must provide sufficient time inschedules to allow for crew rest. Aviationregulations must provide for a proper bal-ance between duty and off-duty periods forflightcrews.

Fatigue is defined as a subjective feeling oftiredness that makes concentration on a taskdifficult. John A. Caldwell, Ph.D., wrote,“As [the pilot’s] fatigue levels increase, ac-curacy and timing degrade, lower standardsof performance are unconsciously accepted,the ability to integrate information from in-dividual flight instruments into a meaning-ful overall pattern is degraded, and a nar-



making it difficult for the pilot to get ade-quate, restful sleep.

Another cause for pilot fatigue is flightacross several time zones—the “jet-lag” phe-nomenon. When flying in a westerly direc-tion, the pilot’s day is lengthened. When fly-ing east, against the movement of the sun,the pilot’s day is shortened. The pilot’s bio-logical clock and the clock on the wall candiffer by several hours.

The effects of disturbing the circadianrhythm can be significant. One investigationshowed that the ability to operate a flightsimulator at night, when compared to nor-mal daytime pilot proficiency, decreased to alevel corresponding to that after moderatealcohol consumption.

Loss of sleep can be cumulative; it is pos-sible to acquire a “sleep debt.” Mark R.Rosekind, Ph.D., et al. wrote, “An individ-ual who requires 8 hours of sleep and ob-tains only 6 hours is essentially sleep-de-prived by 2 hours. If the individual sleepsonly 6 hours [per night] over four nights,then the 2 hours of sleep lost per nightwould accumulate into an 8-hour sleepdebt.”

Sleeping late on weekend mornings is anexample of repaying the sleep debt that hasbeen acquired over several working days.

On average, a person needs 8 hours ofsleep a night. During the remaining 16 hoursof wakefulness, the level of alertness is af-fected by several external factors. These in-

Often, fatigued

persons do not

recognize their

own impair-

ments, but con-

sider themselves

to be fully alert

and capable.

These feelings

may be en-

hanced if the

fatigued person

has tried to off-

set the effects of

fatigue with

stimulants,

such as

amphetamines.

rowing of attention occurs that leads to for-getting or ignoring important aspects offlight tasks.

“In addition, the fatigued pilot tends todecrease physical activity, withdraw fromsocial interaction…and lose the ability to ef-fectively divide his mental resources amongdifferent tasks.”

Generally, performance becomes less con-sistent as sleeplessness increases. Problem-solving slows, motor skills degrade, and theability to pay attention is impaired. A se-verely fatigued pilot may even have tempo-rary perceptual illusions, such as seeinglights that are not present.

An example of the effects of pilot fatigue isthe McDonnell Douglas DC-8 mishap at theU.S. Naval Air Station, Guantanamo Bay,Cuba, on 18 August 1993. This is the firstmajor aircraft mishap in the United States inwhich the National Transportation SafetyBoard (NTSB) cited flightcrew fatigue as theprobable cause. (See “Pilot Fatigue Cited inDC-8 Accident,”on page 18.)

Falling asleep is not a conscious act. Briefperiods of sleep can occur involuntarily, af-ter which the fatigued pilot will not remem-ber falling asleep, or will not have any ideaof how long the sleep lasted. Warnings ofthe onset of sleep include difficulty in focus-ing the eyes or holding the head up; fre-quent yawning; strange or disconnectedthoughts; and erratic flight control, such aswandering off heading or altitude withoutbecoming immediately aware of the varia-tion.

Another common symptom of fatigue is achange of mood. Fatigued persons tend tobe uncharacteristically argumentative or ir-ritable.

Often, fatigued persons do not recognizetheir own impairments, but consider them-selves to be fully alert and capable. Thesefeelings may be enhanced if the fatiguedperson has tried to offset the effects of fa-tigue with stimulants, such as ampheta-mines.

The only way to avoid the effects of fa-tigue is to ensure that adequate, restful sleeptakes place while off duty or between workcycles. There are steps that can be taken toslow the onset of fatigue, but once fatiguesets in, there is no substitute for sleep.

There are several causes for fatigue amongpilots. One cause is nontraditional workschedules, especially night flying, whichdisturbs the pilot’s circadian rhythms—thebody’s normal sleep and wake cycles thatare attuned, respectively, to night and day—


USAF Photo by SSgt Andrew N. Dunaway, ll


Fatigue is also a

personal matter.

A pilot who exer-

cises regularly,

does not smoke

tobacco, eats a

healthy diet,

drinks alcohol

sparingly, and

gets adequate

sleep will be less

susceptible to

fatigue than a

pilot who does

not follow a

healthy

regimen.

The McDonnell Douglas DC-8 was making adaylight approach to Runway 10 at LeewardPoint Airfield, U.S. Naval Station, GuantanamoBay, Cuba, in visual meteorological conditions(VMC) when it struck level terrain in uncon-trolled flight about 0.4 kilometer (0.25 mile) fromthe approach end of the runway.

The plane was destroyed by post–mishap fire.The three flight crewmembers, the only personsaboard the cargo aircraft, received serious in-juries in the 18 August 1993 mishap.

The aircraft was cleared for a landing on Run-way 28, which has an unobstructed approach.The reciprocal Runway 10 required a crosswindleg within 1.65 kilometers (1 mile) of Cuban na-tional airspace, which was restricted from over-flight. The Cuban airspace boundary wasmarked with a fence and a high-intensity flash-ing strobe light; the light was not operational onthe day of the mishap, but the mishap flightcrewwas not provided that information.

At 1641:53, when it was about 118 kilometers(70 nautical miles (nm) south of GuantanamoBay, the mishap aircraft began its letdown from6,710 meters (22,000 feet). At that time, thecaptain said, “Oughta make that one zero ap-proach just for the heck of it to see how it is;why don’t we do that, let’s tell them we’ll take[Runway] one zero; if we miss we’ll just comeback around and land on two eight.”

The aircraft was cleared for landing on Run-way 10, and a right-hand approach (from thesouth) was made.

The following conversation, quoted from theofficial cockpit voice recorder transcript, beginswhen the mishap aircraft was about 3.5 kilome-ters (2 nm) south of the runway.Time Source Content1652:22 Flight engineer slow airspeed1653:28 Captain where’s the strobe1653:29 Flight engineer right over there1653:31 Captain where1653:33 First officer right inside there,

right inside there1653:35 Flight engineer you know, we’re

not getting our air-speed back there

1653:37 Captain where’s the strobe1653:37 First officer right down there1653:41 Captain I still don’t see it1653:42 Flight engineer [expletive] we’re

never goin’ to make this

1653:45 Captain where do you see

clude sensory stimulation, cognitive(conscious) thought content, nutrition,general health, and the presence of anartificial stimulant such as caffeine.

High noise levels on ramps and inflight can contribute to fatigue. Ear-plugs can be worn to reduce noise levelswhile still allowing normal conversa-tion. In the cockpit, noise can also be re-duced by the use of high quality head-sets, some of which are designed fornoise suppression.

Unexpected flight delays, such asthose caused by weather or mainte-nance problems, contribute to the devel-opment of fatigue. When these delays—downtime disruptions—occur during aseries of flights, their cumulative effectcan become serious. Flight delays mayalso result from improper scheduling.For example, a schedule that contains 4hours of duty time, 4 hours of nondutytime followed by another 4 hours ofduty time may, if there are not adequaterest facilities available, be very fatigu-ing.

Even extremes of temperature, suchas would be encountered when takingoff from Scandinavia in January, for ex-ample, and landing in Jamaica, cancause stress, and that may contribute tofatigue.

Fatigue is also a personal matter. A pi-lot who exercises regularly, does notsmoke tobacco, eats a healthy diet,drinks alcohol sparingly, and gets ade-quate sleep will be less susceptible to fa-tigue than a pilot who does not follow ahealthy regimen.

Several measures can be taken to en-courage sleep. When daytime rest isnecessary, a fully darkened room ishighly desirable. If sunlight seepsaround the window shade, maskingtape can be used to make a better lightseal. This technique is also useful atnight if exterior lights illuminate theroom enough to trigger night vision,which will promote wakefulness.

Carrying something from home—forexample, a book to read before sleep-ing—may help the environs seem famil-iar. Setting more than one alarm clock orwakeup call will reduce concern aboutnot awakening on time.

Request hotel rooms located awayfrom traffic or other noises. The temper-ature in the room should be comfort-able. Consider sleeping in the non-

Pilot Fatigue Citedin DC-8 Mishap

continued on page 20


a strobe light1653:48 First officer right over there1653:57 Captain where’s the strobe1653:58 First officer do you think you’re gonna make

this1653:58 Captain yeah…if I can

catch the strobelight

1654:01 First officer five hundred, you’re in goodshape

1654:06 Flight engineer watch the, keepyour airspeed up

1654:09 Sound similar to stall warning1654:10 Unidentified crew stall warning1654:11 Captain I got it1654:12 First officer stall warning1654:13 Flight engineer stall warning1654:13 Captain I got it, back off

The conclusions of the U.S. National TransportationBoard (NTSB) included:

“The flightcrew members had experienced a disruptionof circadian rhythms and sleep loss, which resulted in fa-tigue that had adversely affected their performance dur-ing a critical phase of the flight;

“The captain did not recognize the deteriorating flight-path and airspeed conditions due to preoccupation withlocating the strobe light on the ground. This lack ofrecognition was despite the conflicting remarks made bythe first officer and the flight engineer questioning thesuccess of the approach. Repeated callouts by the flightengineer stating slow airspeed conditions went unheed-ed by the captain; [and,]

“There was no loss of roll authority at the onset of theartificial stall warning (stick shaker) and no evidence toindicate that the captain attempted to take proper correc-tive action at the onset of stick shaker.”

The NTSB accident investigation report determinedthat the probable causes of the mishap included “im-paired judgment, decision-making, and flying capabilitiesof the captain and the flightcrew due to the effects of fa-tigue.”

The report said, “There are at least three core psycho-logical factors to examine when investigating the role offatigue in an incident or accident.”

The first is cumulative sleep loss. The second is thenumber of continuous hours of wakefulness prior the in-cident. The third is the time of day. The report said, “Sci-entific studies have revealed that there are two periodsof maximal sleepiness during a usual 24-hour day. Oneoccurs at night roughly between 3 a.m. and 5 a.m., andthe other in midday roughly between 3 p.m. and 5 p.m.”

The figure shows the sleep/wake histories for themishap flightcrew for the 3 days before the mishap. The

report said, “Overall, this information demonstrates thatthe entire crew displayed cumulative sleep loss and ex-tended periods of continuous wakefulness. It should benoted that the cumulative sleep loss can be partially at-tributed to the reversal of the circadian pattern, withnighttime sleep periods at home followed by daytimesleep periods. Sleep obtained in opposition to the body’scircadian rhythms is more disturbed than sleep that coin-cides with times when the body is programmed forsleep…. Also, the mishap occurred at about 4:56 p.m., inthe 3 p.m. to 5 p.m. window of sleepiness.”

Most critical is the information for the captain who wasthe pilot flying. The report said, “For the entire 65-hourperiod…the captain was awake for 50 hours with 15hours of sleep. Including the 2-hour nap in the last 48hours, the captain was awake for 41 hours with 7 hoursof sleep. In the last 28.5 hours…the captain was awakefor 23.5 hours with 5 hours of sleep.”

These data can be translated into sleep debt based onthe captain’s stated usual sleep requirement of 8 hours.The data show that the captain acquired a personalsleep debt of about 8 hours over the 3-day period, theequivalent of one full night of sleep.

The captain later described his experiences at anNTSB public hearing.

“All I can say is that I was—I felt very lethargic or indif-ferent,” said the captain. “I remember making the turnfrom base to final, but I don’t remember trying to look forthe airport or adding power or decreasing power.

“On the final…I heard Tom [the flight engineer] saysomething about he didn’t like the looks of the ap-proach…it was along the lines of, ‘are we going to makethis?’

“I remember looking over at him, and there again, I re-member—being very lethargic about it or indifferent. Idon’t recall asking him or questioning anybody. I don’t re-call the engineer talking about the airspeeds at all. So it’svery frustrating and disconcerting at night to try to laythere and think of how this—you know—how you couldbe so lethargic when so many things were going on, butthat’s just the way it was.”

A U.S. National Aeronautics and Space Administration(NASA) scientist testified about the captain’s behaviorand associated fixation on the strobe light. He said, “Icounted seven comments in the [CVR] transcript aboutthe strobe. …I think what’s really critical about that isthat…in sleep-loss situations, you get people with tunnelvision. They get fixated on a piece of information to theexclusion of other things. …Right in the middle of [theapproach, the captain] disregards a critical piece of infor-mation[:] the first officer or flight engineer—someonesaying, ‘I don’t know if we’re going to make this.’”


Research has shown that short in-flightnaps increase subsequent pilot wakefulnessand performance on extended flights.

In a joint study conducted by NASA in1994, the effectiveness of planned cockpitcrew rest was tested. In the test, two groupsof crewmembers made the same 9-hourtrans-Pacific flight, but one group was al-lowed a 40-minute nap during a low-work-load period of the flight.

Ninety-three percent of the crewmemberswho were allowed to nap were able to fallasleep, and they slept for an average of 26minutes. After waking, they showed betterperformance (based on reaction time andvigilance) and higher alertness (measured bybrain waves and eye movements) than thegroup of pilots who had not napped.

Nevertheless, there are two potential neg-ative effects of such naps. The first is sleepinertia, or the grogginess and disorientationthat may occur on first awakening from adeep sleep. Sleep inertia can last for a fewminutes or as long as a half an hour, butgenerally dissipates within 10 minutes to 15minutes. The second potential negative isthe effect of a nap on subsequent sleep peri-ods. A recent nap may make it difficult for thecrewmember to sleep during the normalground resting time.

Some airlines, acknowledging the debilitat-ing effects of in-flight fatigue on pilot perfor-mance, have established formal policies forproviding pilots in both two- and three-per-son crews with the opportunity for controlledrest.

Lufthansa German Airlines, Swissair, andBritish Airways allow planned in-flight crew

rest during low-workload periods near theend of the flight, but not within the 30 min-utes before beginning the letdown to theirdestination. Generally, rest periods are from30 minutes to 45 minutes, only onecrewmember may rest at any one time, andrest is taken in the respective pilot’s cockpitseat. Eyeshades and earplugs may be used,if desired, to help the resting pilot fall asleep.Depending on the airline, the preflight plan-ning includes the crew-rest sequence, crite-ria for unplanned wakeup, and coordinationwith cabin staff.

Air Canada presently has no provisions forin-flight crew rest, but has submitted a re-quest to Transport Canada to begin a testprogram of methods and procedures for al-lowing pilots on long flights to sleep for shortperiods before starting letdown to landing.The Air Canada test, if authorized, will beconducted in airplanes with three-pilot flight-crews.

KLM Royal Dutch Airlines also has con-trolled flight-deck crew rest under considera-tion.

For U.S. air carriers, regulations for crewscheduling and crew rest are promulgated inthe U.S. Federal Aviation Regulations(FARs). The FARs specify the maximumnumber of accumulated flight hours permit-ted within certain calendar periods, how andwhen ground rest periods are scheduled,how duty time is defined, and conditions un-der which a flightcrew member may exceedthe stated flight time limitations without beingconsidered in violation of regulations. Never-theless, the FARs make no reference to con-trolled crew rest.

smoking section of the hotel, where cough-ing is less likely to be heard.

If a pilot cannot avoid being on duty whilefatigued, there are short-term measures thatcan be taken to reduce the effects of fatigue.

✗ Eating high-protein foods and drinkingplenty of water can temporarily offset fa-tigue.

✗ Caffeinated beverages can temporarilyenhance alertness.

✗ Talking with other crewmembers; get-ting out of the seat; and moving about theaircraft for a few minutes will tend to pro-mote wakefulness.

Generally speaking, pilots who transitionto a new time zone or work schedule for ashort period should not try to readjust theircircadian rhythms to the new environment.Circadian rhythms change slowly, some-times by as little as 11/2 hours per day. Asmuch as possible, temporarily transplantedpilots should maintain their usual circadianschedule—sleep and rest on their “at-home”clocks.

Fatigue is manageable. A better under-standing of its causes and consequences en-sures that pilots are fully alert while onduty

Some Airlines Permit Pilots to Nap During Long Flights

Even extremes

of temperature,

such as would

be encountered

when taking

off from

Scandinavia in

January, for

example, and

landing in

Jamaica,

can cause

stress, and that

may contribute

to fatigue.


The weather report for our pilot proficiency flightwas about average for a fall day on the centralCalifornia coast—rain, with thunderstorms likely

in the Central Valley. The high desert and San JoaquinValley were calling for slightly more than marginalVFR, and we elected to bounce at Palmdale and NASLemoore.

Preflight went normally, and after the usually hectictakeoff and departure from the San Francisco Bay area,we settled in for the flight to Palmdale. Using oursearch radar to dodge the heavier cells, we made ourway toward Palmdale, finally breaking out of the heav-ier stuff about 50 miles north of the field. Edwards Ap-proach reported isolated cells, but VFR conditions ex-isted over most of the Antelope Valley area.

Approach vectored us for a straight-in ILS andpassed a report of a shower at the field. Rolling out onfinal, we saw the cell, and things began to get interest-ing. The cell covered the entire field but did not totallyobscure the runway. Around its periphery, we couldsee swirling dust where the downdrafts were hittingthe ground. Neither approach nor tower had any re-ports of downdrafts.

Realizing that this might be a microburst, the captainelected to continue the approach, but at about 1,500 feetAGL. As we approached the field, we could see thatthe worst of the dust swirls were around the middlemarker. As the off-duty pilot, I was able to snap a fewquick photos during the approach.

As we entered the cell, we experienced moderate tur-bulence, about a 10-knot (kt) increase in airspeed, and a2,000-fpm rate of descent. Passing out the other side,we lost about 15 to 20 kts and felt the same turbulenceand rate of descent. We passed a PIREP to the towerabout the size and strength of the downdraft. We heldbriefly until the cell passed and then completed the re-mainder of the flight without incident. Back home, Italked to the weather guessers who confirmed we had,in fact, tangled with a microburst.

We were lucky. The conditions that day let us see themicroburst and successfully avoid it. In the process, allthree pilots got valuable training and a new respect forthunderstorms and convective weather.

We could have been very unlucky. Had we been onthe normal ILS profile, we’d have hit the microburstjust at decision height, dirty and slow; the ride wouldhave been much worse. It could have even been fatal.

There are some important questions to be asked.What if the field had been at minimums and nobodywas aware of the microburst’s presence? What if wehad been returning from an all-night tactical event,tired, eager to land? What if…what if?

We saw, we stayed high, we survived.

BOB BROADSTONBusiness Aviation Safety Journal, Vol 10, 1995Courtesy Approach Magazine

WHAT IF?What if? In past years, civilian aviators have placed a

lot of emphasis on aircrew training for microbursts.Commercial airlines have developed standard operatingprocedures for both takeoff and approach. This em-phasis is a result of the increased number of civilianmishaps attributed to microbursts.

These mishaps include:• 24 June 1956: BOAC Argonaut at Kano, Nigeria; 32

killed, 11 injured.• 30 January 1974: PAA Flight 759 at Pago Pago,

American Samoa; 96 killed.• 24 June 1975: Eastern Airlines B-727 at JFK, New

York; 112 killed, 12 injured.• 7 August 1975: Continental Flight 426 at Denver; 15

injured.• 14 May 1976: Royal Jordanian Flight 600 at Doha,

Qatar; 45 killed, 15 injured.• 23 June 1976: Allegheny Flight 121 at Philadelphia;

86 injured.• 3 June 1977: Continental DC-9 at Tucson. No in-

juries; power line severed.• 2 August 1985: Delta L-1011 at DFW. Multiple casu-

alties.These mishaps brought on an aggressive attempt by

the airlines to eliminate this type of mishap throughpilot training and standard operating procedures.

Ka-Boom!!! Y o u ’ r ec r u i s i n g

along at altitude when suddenly a “big-bang” thunders in your ears. Regainingyour composure as the ringing in your earssubsides, you ask yourself, “What in theheck was that?” Cross-checking your instru-ment panel, you’re relieved to find that all ofyour avionics are operating normally.Thinking about what just happened, you re-member flying through heavy rain showersand light turbulence and requesting clear-ance to climb to a higher altitude. You winceas you recall the static you heard over the ra-dio as you called ATC. You realize yourclimb took you thorough the freezing lev-el—and then the “ka-boom”!

By now you’re beginning to recognizeyou’ve suffered a lightning strike. But didyou know that lightning strikes and electro-static discharges are the leading causes ofweather-related aircraft incidents in the AirForce? Perhaps not. Did you know that re-cent mishap reports suggest you may not beaware of the difference between lightning


strikes and electrostatic discharges? This ar-ticle, hopefully, will shed some light on thissubject (no pun intended) and help youavoid the hazards posed by lightning.

Actually, it’s fairly easy to see how the twocould be confused. There are, however,clear-cut differences between lightningstrikes and electrostatic discharges. We com-monly refer to an electrostatic discharge as“static electricity”—something we’ve all ex-perienced. For example, remember the an-noying shock you got when you walkedacross a carpeted floor and touched an ob-ject or another person? Likewise, as youraircraft moves through a cloud, precipita-tion or solid particles such as dust, haze, andice, can induce a charge on the fuselage ex-terior. This charge interacts with an oppositecharge in the surrounding atmosphere totrigger the electrostatic discharge.

Mr. Dennis Baseley, technical advisor onelectromagnetic effects at the AeronauticalSystems Center at Wright-Patterson AFB,Ohio, provides a deeper insight into thisphenomenon. In his description of electro-static discharges, he states, “Precipitationstatic (p-static) occurs on the trailing or oth-er sharp edges of the aircraft. To prevent p-

MAJ ELIZABETH A. COATESChief, Weather ProgramsAF Flight Standards Agency/XOFD

When Lightning Strikes

When Lightning Strikes



P-static

dischargers

should not be

confused with

lightning protec-

tion devices, al-

though they

may serve as a

convenient exit

point for light-

ning and reduce

damage to the

aircraft structure.

In short, many

aircrews mistak-

enly report elec-

trostatic dis-

charges as

lightning strikes.

static from being heard on the radios in theform of static, aircraft are equipped with p-static dischargers at these points.

“Furthermore, it’s a misconception thatdischarges produce bright flashes or loudnoises, because p-static dischargers reducethe charge to lower levels before they can beaudibly detected. Additionally, p-static dis-chargers should not be confused with light-ning protection devices, although they mayserve as a convenient exit point for lightningand reduce damage to the aircraft structure.In short, many aircrews mistakenly reportelectrostatic discharges as lightning strikes.”

Bearing in mind Mr. Baseley’s comments,we can build upon our understanding of thedifferences between static discharges andlightning strikes by taking a closer look atlightning. Lightning is one of the many haz-ards associated with thunderstorm activityand may occur at any level within a thun-derstorm or even outside of a thunderstorm.As air currents rise and fall within a thun-derstorm, positive and negative chargesseparate within the cloud (see figure 1). Pri-or to a cloud-to-ground strike, these chargecenters induce an opposite charge area overthe ground. When the negative charge—for-mally called the “step leader”—meets thepositive charge, a lightning discharge or

flash results.In like man-

ner, as chargecenters sepa-rate, dischargesalso occur in-side and be-tween clouds.In fact, mostlightning neverhits the ground,but occurs with-in these areas.One recentstudy indicatedthat the anvil of a thundercloud (the flat up-per portion of the cloud so named becauseof its flat appearance) is particularly unsafedue to the presence of such electricalcharges1.

In addition, NASA research indicates anaircraft is more likely to be struck by light-ning when it penetrates the upper reaches ofa thunderstorm (35,000 to 40,000 feet) andambient temperatures are near -40°C2.

It’s important to remember that lightningstrikes not only occur within cells, but mayalso occur in the clear air around the top,sides, and bottom of a storm. Often a “boltout of the blue” can occur several miles from

Graphic by Felicia MorelandFigure 1


So where does

the static you

hear over your

radios and your

interphone

come from?

Aside from the

p-static effects,

what you re

hearing is a

noisy announce-

ment that a

lightning strike is

about to

happen.

a thunderstorm cell (see figure 2).So where does the static you hear over

your radios and your interphone comefrom? Aside from the p-static effects, whatyou’re hearing is a noisy announcement thata lightning strike is about to happen. Thestatic heard by the aircrew is an approachingstep leader. It’s Mother Nature’s way ofwarning the crew to quickly move awayfrom these conditions.

Still, there may be some gray areas whereit’s difficult to determine the difference be-tween a lightning strike and an electrostaticdischarge. Our data shows that the majorityof Air Force lightning strikes occur at low al-titudes in seemingly benign clouds and inareas outside of active thunderstorm cells.

Not surprisingly, several recent researchprograms, including the NASA Storm Haz-ards Program (1980-1986), USAF/FAALightning Characterization Program (1984-85, 87), and the French/Transall Program(1984, 1988), found that aircraft trigger 90percent of the lightning strikes at low alti-tudes outside of thunderstorms3. They do

this by providing thepath of least resis-tance between twoopposite-chargedelectrical centers. Ifthe aircraft were notpresent, these strikeswould not occur.

Electrically activezones have been ob-served in stratifiedclouds which havelight to moderateprecipitation, clouddepths greater than 1km, and widths ofup to several kilome-ters, light turbu-lence, and tempera-tures ranging from -6to 11°C (near freez-ing). Under theseconditions, precipi-tation such as mixedsnow, sleet, and rain,in addition to in-creased vertical in-stability, increasesthe electrificationwithin the cloud4. Asa rule of thumb, pi-lots can reduce thechances of being hitby lightning by not

flying in the following conditions:Within 8°C of the freezing level.Within 5,000 feet of the freezing level.In light precipitation (including snow).In clouds (including debris clouds).In light or negligible turbulence5.

But wait, what about the old saying,“Lightning never strikes twice.” Well, thisjust is not true. A study of lightning strikeson the Empire State Building in New YorkCity revealed an average of 23 strikes peryear. During the same study, as many as 48strikes were recorded in one year, and dur-ing one thunderstorm, eight strikes oc-curred within 24 minutes6. Like the EmpireState Building, your aircraft is subject tomultiple strikes. In a recent mishap, one air-craft reported being struck twice within amatter of minutes. So, if you ever encountera lightning strike to your aircraft, exit thearea quickly or you may get another jolt.

What happens if you and your aircraft arestuck by lightning? The physiological in-juries can range in severity from “none” to“fatal” and include various degrees of

Figure 2


Like the Empire

State Building,

your aircraft is

subject to

multiple strikes.

In a recent

mishap, one

aircraft reported

being struck

twice within a

matter of

minutes. So, if

you ever en-

counter a

lightning strike

to your aircraft,

exit the area

quickly or

you may get

another jolt.

burns, deafness, and flash blindness. Hav-ing your hair stand on end and/or feeling aslight tingling sensation in your skin indi-cates a building charge and a pending strike.

While most aircraft can survive a strike,lightning causes both direct and indirect ef-fects (damage). Direct effects include fuse-lage punctures, damage or destruction ofthe radome, and burning, melting, or distor-tion of aircraft metallic and nonmetallicstructures. In a worst case scenario, a light-ning strike can cause a fire in the fuel sys-tem. Indirect effects include temporary orpermanent damage to electronic circuitsfrom the strong electric/magnetic fieldscaused by the lightning strike.

Now that you know the risks posed bylightning and electrostatic discharges, whatcan you do to protect yourself? You can startby following MAJCOM guidance and thesafety measures discussed in this article. Forinstance, the next time you encounter the at-mospheric conditions listed above, avoidthem if at all possible. Unless perhaps you’dprefer a not-too-subtle reminder from Moth-er Nature…

Find out more about AF Weather Pro-grams at the Headquarters Air Force FlightStandards Agency Web site:http://www.andrews.af.mil/tenants/affsa/3frames.htm

Sources:1. Marshall, Thomas C. (NASA Langley Re-

search Center) et al, The Electrical Structure ofThunderstorm Anvils, Volume 1, 1991 Internation-al Aerospace and Ground Conference on Light-ning and Static Electricity, Vol 1991

2. Fisher, Bruce D. (NASA Langley ResearchCenter, Hampton VA, USA), Effects of Lightning onAerospace Vehicles, Conference Paper, Flight inAdverse Environmental Conditions, 1989

3. Mazur, Vladislav (National Severe StormsLab, Norman OK, United States), Lightning Threatto Aircraft: Do We Know All We Need to Know?,Conference Paper, The 1991 International Aero-space and Ground Conference on Lightning andStatic Electricity, Vol I, 1991

4. Rust and MacGorman, Electrical Nature ofStorms, Oxford Press, NY, NY, 1996

5. AFJH 11-203, Vol.1 Weather For Aircrews, 1 March 1997

6. Uman, Martin, Understanding Lightning, BekTechnical Publications Inc., Carnegie PA, 1971

Did you know that there was achange to the METAR/TAF Code?? Ef-fective 1 November 1998, the WorldMeteorological Organization (WMO)changed the code for ice pellets from“PE” to “PL.” Example (excerpt fromactual TAF):“…BECMG 1314 0812G27KT 1600 -FZRAPE BR OVC004 690002640505 540008 QNH3027INS”would now read “…BECMG 13140812G27KT 1600 -FZRAPL BROVC004 690002 640505 540008QNH3027INS”


Training students in the little Tweet was hardlysomething you bragged about. It was slow and itwas noisy. It didn’t go very far and it was noisy.

In the summer it was hot and it was noisy. It took for-ever to climb high enough to do spins. But it sure wasa good teaching tool. I learned a lesson almost everytime I flew.

On one summer sortie at a southwestern base, I hadclimbed to the top of the high areas to accomplish someneeded spin training. During the brief time we were ataltitude, the typical afternoon buildups started. Eventu-ally we were squeezed into one corner of the area in or-der to avoid spinning above the clouds. When Centerannounced the SOF’s weather recall for potential thun-derstorms over the base, I was ready to go home.

Looking from our area back toward the common re-covery point out of the areas, I noticed two of the big-ger towering cu’s on either side of our usual route. Nei-ther had reached much over 20,000 feet, and neitherhad anything resembling an anvil. I couldn’t even seeanything falling from the bases.

Since we were the only Tweet in the area, I was givenan immediate descent to the recovery point. The twobuildups appeared to be about 10 miles apart, so Iplanned to fly between the two towering columns andstay in the clear all the way home. It looked like the skybetween them was blue and clear. At 200 KIAS, withthe speedbrake extended, and using frequent valsalvas,we were “racing” downhill for home.

Suddenly we flew into a rain shower. The precipita-tion was so heavy we lost all forward visibility. Thenoise was so great we couldn’t hear each other over theintercom. The shower lasted for about 7 or 8 seconds.As suddenly as it started, it was over, and we wereback in the clear. I hardly had enough time to get mycross-cockpit instrument scan going.

Before I had a chance to say a word, the student mut-tered “Jeeez!” from the left seat.

“What is it?” I asked.“Look at the wing,” he answered.I leaned over to see what was wrong with the left

wing. I really couldn’t see anything, and he finally said,“It’s the intake.”

Looking over my own canopy rail, I saw the fiber-glass intake was thoroughly stripped of paint, and a lotof it had been delaminated. I declared a “precaution-ary” recovery with the SOF and returned straight homewithout a stop at the aux field.

The safety shop and the fire department met us as wecleared the runway. Before we could unstrap and climbout, all of the people on the ground were pointing atour jet and walking closer for a better view. After step-ping over the side, I was as speechless as the peoplewho met us. Every light (taxi light, “passing” light,wing tip, beacon, and strobe light) was gone. The entirespeedbrake surface looked like a wild man with a ballpeen hammer had pounded every square inch. Thefiberglass intakes and the leading edge of the wing tipswere stripped of paint and nearly peeled away as if hitwith a giant sandblaster. The leading edge of the verti-cal and horizontal tails were seriously dented. Clearly,we had not flown through a rain shower. We had spent7 or 8 seconds in some major hail.

Despite the apparent lack of thunderstorm character-istics, the towering cu’s were indeed growing thunder-storms. Even without an anvil, they were capable ofproducing major hail. My somewhat casual treatmentof these clouds led me to believe it was “safe” to fly be-tween them. Blue skies above and small buildingclouds were no insurance against the power of nature.

Since that day, if I even suspect there’s a chanceclouds might be potential thunderstorms, I’ve giventhem a wide berth. Even the slow Tweet can make dou-ble-digit distances around building weather with ease.Besides, even the Tweet deserves better treatment thanI gave it around thunderstorms.

Flying Safety, August 1993

Official USAF Photo


■ FL180 is the altitude at or above which all aircraft al-timeters should be set at 29.92, and below which theyshould be set to the current barometric pressure of thenearest reporting station. A frequently reported causefor altimeter mis-setting incidentsthat occur during a climb or descentthrough this altitude is distractionby other cockpit tasks. In a report toASRS from an air carrier captain,distractions inside and outside thecockpit, including a mechanicalmalfunction, led to an altitude devi-ation.

While descending through approxi-mately 23,000 feet and navigating anarea of precipitation and thunderstorms,both air-conditioning packs failed…Aswe worked on the pressurization prob-lem…we were assigned 11,000 feet. Aswe leveled, ATC asked our altitude be-cause he saw us at approximately10,500 feet. Then we noticed that two of our altimeters werestill set at 29.92 with the pressure at 29.42. Our workloadwas obviously heavy, but we should not have missed this ba-sic procedure. Someone always must pay attention to flying.

A 1997 ASRS study on flightcrew monitoring inci-dents found that a majority of such incidents occurredwhen the aircraft was in a “vertical” flight mode—climbing or descending. Flightcrews also were morelikely to experience monitoring errors while perform-ing two or more flight-related tasks—like the crew inthis report which was avoiding weather, dealing with apressurization problem, and talking to ATC, all whiledescending through FL180.

As our reporter noted, appropriate division of cock-pit tasks (one pilot to fly the aircraft, the other to han-dle the malfunction), and adherence to procedures (thechecklist) probably would have allowed the flightcrewto catch this mistake before ATC did.

12 O’Clock HighAn air carrier crew’s altitude problem started during

preflight, when they failed to notice that their altimeterneedles were aligned at the “12 o’clock” position—atan airport with a field elevation of 1,000 feet MSL. TheFirst Officer reports:

After we leveled at 11,000 feet, Center said to descend andmaintain 11,000 feet. We replied that we were level at 11,000feet. About a minute later, Center again said to descend andmaintain 11,000 feet. They said they showed us level at12,000 feet and pointed out traffic at 13,000 feet. About thattime, we discovered that the altimeters were set to 28.88 in-

stead of the proper setting of 29.88. We quickly descended to11,000 feet.

The night before, maintenance personnel had dialed bothaltimeters back to sea level…[the actual] field elevation is ap-proximately 1,000 feet MSL. We accomplished all checklistson preflight, but failed to notice that the second digit [of thebarometric setting indicator] had been set to an 8 instead of a9. This is something that is easy to miss.

High to Low, Look Out BelowThe rapidly changing weather

associated with cold fronts andsteep frontal slopes can create sig-nificant and sudden drops in baro-metric pressure, causing some pi-lots to mis-set their altimeters. Anair carrier captain provides an ex-ample:

During descent below FL180, I put29.82 into my altimeter. When theFirst Officer (FO) came back from talk-ing to company on the No. 2 radio, healso put 29.82 into his altimeter. Wewere descending through 6,000 feet for5,400 feet when the Approach Con-

troller announced a ground proximity alert and told us toclimb immediately to 6,000 feet and to recheck our altimetersat 28.82. We started to climb, checked our altimeters, anddiscovered our mistake…

It was an unusually low altimeter setting that day. Boththe FO and I wrote the correct altimeter setting on our notepads, and both of us mis-set our altimeters.

Unusually low barometric pressures may take pilotsby surprise, especially if the weather appears to be im-proving, leading the crew to believe that a higher al-timeter setting looks plausible. The old adage, “High tolow, look out below” is still sound advice.

Flying into cold air has the same effect as flying intoa low-pressure area; that is, the aircraft is lower than thealtimeter indicates. Altimeters cannot be corrected fortemperature-related errors. However, pilots can adjusttheir minimum procedure altitudes to compensate forextremely low temperatures. Canadian pilots consult agovernment-provided chart to determine how much al-titude to add to the procedure altitudes listed on ap-proach charts, thus ensuring obstacle clearance duringvery low temperature operations. The U.S. DefenseMapping Agency publishes a similar altitude correctiontable for military pilots. Readers who would like moreinformation about low temperature correction chartsshould refer to ASRS Directline, Issue No. 9, availableon the ASRS Web site at http://olias.arc.nasa.gov/asrs

Editor’s note: See also the related story, “It’s Cold Out Here!” in theOctober 1998 issue of Flying Safety magazine.

Courtesy Callback, No. 233, Nov 98NASA’s Aviation Safety Reporting System (ASRS)

Altimeter Settings Revisited

Felicia Moreland


AME1(AW) ANDREW SMITHCourtesy Mech, Jul-Sep 98

…33 deaths, most of them caused by humanerror, as opposed to equipment failure.

Recently, I swapped sea storieswith a civilian ejection-seat rep.Our conversation turned to seat

safety. I asked him how manyAMEs (aviation structural mechan-ic safety equipmentmen) had beenhurt or killed during arming andde-arming-related accidents. To mysurprise, he said he knew of 33deaths, and, believe it or not, mostof them were caused by human er-ror, as opposed to equipment fail-ure. The most important error wasnot using a checklist.

I’ve been in the Navy 18 years, sonothing I hear surprises me, exceptmaybe a good sea story. When theconversation ended, I walked intothe hangar and watched severalpeople from different squadronsworking in and around aircraft. Ididn’t see any of them check if thesafety pins were in place beforethey climbed into a cockpit. Notone! It made me see the careless-

ness of many people workingaround a seat designed to eject aperson out of the aircraft. That’slike crossing a street without look-ing for traffic.

An ejection seat doesn’t care whoyou are—an aircrew member eject-ing in an emergency or a techniciancorrecting a problem. An ejectionseat has but one purpose: to throwa body into the air. If a hangar-deckceiling happens to get in the way,that isn’t the seat’s problem—it’sdone its job. The safety pins in-stalled on ejection seats are not cos-metic. They are there to protect youwhile you do maintenance. Checkthose pins.

Where Are Those Safety Guys?

AT2 ROBERT GILMORECourtesy Mech, Jul-Sep 97

When deployed, it’s easy to spotthe safety reps in their white jer-seys with green crosses. Squadronsalso have QARs (quality assurancerepresentatives) who constantly re-mind us about hazards, and everywork center has an assigned SafetyPetty Officer (PO). You’d thinkthere would never be a time whenthere wasn’t a safety guy around.

Our squadron embarked after be-ing on the beach for a few months.Our safety department was particu-larly wary because we had severalfolks getting their first flightdeckexperience, and most of us old salts

were a bit rusty. The potential formistakes was high, as was the riskof injury.

One day early in the deployment,I watched someone wearing aclean, new jersey (obviously a rook-ie on the flight deck) walk throughthe static prop arc of an E-2C Hawk-eye. I thought how lucky he wasthat a safety guy hadn’t seen him.

A little later, I noticed blueshirtschaining down aircraft with thetiedown hooks facing down in thepadeyes. No safety guys aroundthis time, either.

Then I watched someone give hisbuddy change for a soda right out ofhis pocket in the middle of the flightdeck, and he didn’t even have aFOD pouch! I expected a safety guyto stop this exchange any second

and quickly escort this sailor off theflight deck, but no one showed up.

Then it finally occurred to methat I was a part of the problem. Icould have stopped the new guywalking through the prop arc, cor-rected the blueshirts’ tiedown pro-cedures, and escorted the humanchange machine off the flight deckmyself.

We can’t expect only those wear-ing white jerseys or with titles likeQAR or Safety PO to keep our safe-ty programs intact. I taught myselfa valuable lesson in leadership thatday and answered my own ques-tion: Those safety guys are every-where; you only have to look in themirror.

Checking Those Pins Might Save YourLife


Planes, Trucks, and Automobiles

Planes, Trucks, and Automobiles, PartOne: The Falcon as prey. Visibilitywas clear and a million, and it wasanother normal day shift for thetwo security forces troops pa-trolling in their vehicle. Everythingseemed quite routine. Maybe a lit-tle too routine. Along with theirother responsibilities, they were re-quired to patrol the F-16 flightlinerestricted areas periodically to en-sure all was secure. That’s whatthey were doing, and things werefine until the driver decided to takea shortcut between two aircraftparked side by side. Note for non-Falcon types: There isn’t much roombetween the wingtips of two parkedF-16s; even less when a fire bottle isalso present. He tried to sidestep thefire bottle while maneuvering hisvehicle between the wingtips, butthe passenger side of the vehiclestruck one of the F-16s. Cost:$16,000 damage to the electric jetand $1,300 damage to the patrol ve-hicle.

Planes, Trucks, and Automobiles,Part Two: Three strikes, you’re out. Aservicing truck was being posi-tioned in order to service the aft la-trine on a C-9. This particular vehi-cle was equipped with a cage ontop for holding the suction hose.The driver and operator were ac-customed to using servicing trucksthat weren’t equipped with this cage

(strike one). And, since the suctionhose on this particular vehicle hadbeen shortened so that it wouldwork more efficiently, it also meantthe servicing crew would have toposition their vehicle closer thancustomary to the aircraft (striketwo). The stage for the mishap wasset when the crew failed to proper-ly fix chocks behind the rear wheelsto prevent inadvertent contact be-tween the vehicle and the aircraft.As the servicing truck backed intoposition to commence servicing,the cage on the vehicle hit the No. 1engine cowling (strike three). Allthings considered, damage to theaircraft could have been muchmore serious—total mishap costwas only about $100. But based onall the unwanted attention thesemechanics received, we’re betting itseemed a lot more costly than that.

Planes, Trucks, and Automobiles,Part Three: The hazards of task satura-tion. Due to a manning shortage,the maintainer was involved in twoseparate tasks simultaneously. Itwas 0430 in the morning—a time ofday when our internal clocks makeus especially vulnerable to mentallapses—and he was tasked to worktwo F-16s parked side by side. Air-craft A required a power-on opcheck, and Aircraft B needed to berefueled. He called for the refuel,and after being advised therewould be a short delay, drove hissix-pack truck to the AGE sub-pool

to pick up a dash-60 for the power-on op check on Aircraft A. He hadno sooner returned with the dash-60, parked in front of Aircraft A,and connected the power unit cordto the aircraft, than the refuel truckarrived next door for Aircraft B. Re-alizing then that he didn’t have thenecessary job guide for the refuel,he walked over to the refuel truckdriver and told him he was goingto Support Section to get tech dataand would be right back. Hewalked back over to his six-pack,hopped in, and pulled away. Un-fortunately, the dash-60 was stillconnected to Aircraft A. The F-16suffered damage that included abroken nose gear door, power re-ceptacle, and landing light bracket,and the power unit’s cord and oth-er items needed repair. Total repaircost for the aircraft and dash-60?More than $15,000.

The one bright spot apparent inthese three mishaps is that nobodywas injured. Reminder: All of usmake mistakes. If you witness anunsafe act—whether it’s deliberateor inadvertent—intervene and pre-vent that unsafe action from contin-uing. You and your coworkers areall part of the same team, andwhen unsafe acts are prevented, theteam wins. Work smart, look outfor each other, and above all, besafe!

30 FLYING SAFETY ● MAY 1999 ✩ U.S. GOVERNMENT PRINTING OFFICE 1998-673-366/43052

Can an instrument pilot ever knowtoo much about flying? I wouldsay no; however, I would add the

caveat that you’d better understandhow to use the data you’ve ingested.Most instrument pilots can tell you a lo-calizer is good out to 18 miles unlesspublished otherwise. How does this in-formation help us? It’s nice to know,but it may do more harm than good ifwe erroneously use this information.

Look at the ILS RWY 15 Dallas/Addi-son (see the figure). If we get vectors tofinal (and we have to in this case),when can we descend to 2200’/2000’ af-ter being cleared on the ILS or localizerapproach? Federal Aviation Regulation(FAR) 91.175(i) and AFM 11-217 statethat we must maintain the last assignedaltitude until we are on a publishedrouting or a portion of the IAP (initialapproach point). The localizer is goodout to 18 miles, so we should be goodto descend once we are inside 18 DME(distance measuring equipment), right?Wrong!

Regardless of the fact that the servicevolume of the localizer is 18 miles, theILS/LOC protected airspace goes outonly to 5.5 DME for the ILS 15 ADS.TERPs (Terminal Procedures) states thatthe length of the area considered for ob-stacle clearance is the area between theglideslope intercept point and a point200 feet from the threshold. On a local-izer, it’s the area between the FAF (finalapproach fix) and the MAP (middle ap-proach point). Beyond the glideslope in-tercept point or the FAF, the final portion of an IAPdoesn’t exist.

This type of approach has a radar intermediate seg-ment that will not be shown on the published IAP. Theintent of a final-only approach is to let ATC vector youto final at the MVA. You may then descend to yourMDA/DH at the FAF/glideslope intercept point. Thisworks fine as long as the MVA is the same as theFAF/glideslope intercept point and ATC vectors you at

CAPT J. C. FINDLEYAdvanced Instrument Flight SchoolRandolph AFB, Texas

this altitude. What if ATC vectors you in at 3,000 feet oreven 4,000 feet for the ILS 15 ADS? You may not de-scend from your assigned altitude until you get to 5.5DME. If the descent gradient is unacceptable, it’s yourresponsibility to get a lower altitude assigned or tell ap-proach you cannot accept the approach clearance.

These final-only IAPs are designed to be easy to fly.They are, as long as both ATC and the pilot understandhow to use them. Take care, and fly safely.

SMSGT DAVID P. SANDO429th Electronic Combat Squadron

Cannon AFB, New Mexico

During a squadron sortie surge, SMSgt Sando was in the QualityAssurance office clearing an aircraft impoundment when he overheardthe wing FOD NCO discussing an unidentified part found on the active

runway earlier that morning. His curiosity pulled him into the conversationwhere he immediately identified the part as an EF-111A main landing gear strutretaining pin bolt.

Aware of the possible repercussions from this part not being on the aircraft,SMSgt Sando immediately called the production superintendent and instructedhim to stop the launch of the day’s first sorties, which were preparing to taxi atthe time. He then directed an immediate inspection of all aircraft on the flight-line to identify which one the part came from.

The subsequent inspection revealed the bolt was missing from the left mainlanding gear strut retaining pin on aircraft 67-0037. This aircraft was scheduledto fly that day. The investigation found the strut retaining pin had broken in half,allowing the bolt to fall out. The aircraft had flown the night before and theassembly had failed upon landing.

Had SMSgt Sando not immediately identified the part and taken decisiveaction to ground the fleet for a one-time inspection, the landing gear on 67-0037would have definitely malfunctioned. Had the aircraft taken off, the left side ofthe gear would have been dangling, the gear door would not have closed, andthe aircraft would not have been able to land—forcing the crew into a controlledejection situation.

WELL DONE!(Since this event occurred, SMSgt Sando has been reassigned. He is currently

the Maintenance Flight Flight Chief for the 49th Maintenance Squadron atHolloman AFB, New Mexico.)

The difference between failure and success is doing a thing almost right and doing it exactly right.

The difference between failure and success is doing a thing almost right and doing it exactly right.

E.C. McKenzie

Date post:	18-Dec-2021
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