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OPPORTUNITIES FOR AND VULNERABILITIES TO ERROR

IN EVERYDAY FLIGHT OPERATIONS

Loukia D. Loukopoulos

Key Dismukes & Immanuel Barshi

NASA Ames Research Center, Moffett Field, CA

ATA/CRM ConferenceMARCH 2002

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Opportunities for and vulnerabilities to ERROR in everyday flight operations

• research-oriented, theoretical approach• errors happen even to the most expert pilots - why?

Presented earlier this year at FAA annual review meetingDiscussed in the context of Rapid Response Team’s recommendations

regarding security measures

Implications?• workload and distractions• how will measures, both outside and inside, the cockpit affect pilots’

performance?• how to avoid unintended opportunities for error?

BACKGROUND

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Errors in everyday flight operations pre-9/11

Opportunities for error in work environment (operational factors)

A qualitative analysis of line operations• field observations (N=50)• two U.S. carriers, B737• contrast between training and operating environment• evidence from incident reportsFocus on preflight and taxi

Vulnerabilities inherent in human cognitive abilities (cognitive factors)

Memory and attention limitations

OUTLINE

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“… error in everyday flight operations”

“This would never happen to us…”

PREFLIGHT: While doing Before Start Engine checklist the agent brought in a jumpseat rider and I allowed the checklist to be interrupted. Engine Start and Push Back were normal. During Taxi I noticed the seat belt switch was in the “off” position. (ASRS 400770)

PUSHBACK: CA became involved in discussion regarding taxi instructions with FO just after communication with tug attendant. Assuming that tug had departed and that previous communication was confirmation of that, CA applied power to taxi and struck the tug. (NTSB CHI95LA170)

TAXI: FO busy starting #2 engine, then doing the After Start flow and Taxi flow in time to run the Taxi checklist prior to reaching the runway. CA taxied past the Hold Short line. (ASRS 317660)

CLIMB: Climbing through 16000ft, FA called and inquired about seat belt, rough ride, thunderstorms etc. This got both pilots occupied and to forget to do the Climb checklist, thus missing the altimeter setting change to 29.92. (ASRS 394580)

CRUISE: Master caution light illuminated. Preoccupied with handling problem (duct overheat), handling radios, stowing charts. Did not notice strong wind had blown aircraft E of course. (ASRS 427840)

APPROACH: Inbound to destination airport, thunderstorms all around. Unable to comply with instructions to hold at standard hold fix, then alternate fixes due to weather. Cleared to third hold fix. Meanwhile checking fuel, weather at alternate, talking to company, making PA, and interrupted by FA. Crew neglected to finish Descent checklist which was started several times. (ASRS 402510)

LANDING: While on visual approach crew could not get the ILS to tune or display. PM was busy trying to resolve the problem. Once inside the OM, both pilots turned their attention to the landing. With no one ahead of them and the runway clear, they missed the frequency change to Tower and landed while still on Approach frequency. (ASRS 453870)

Note: assume through flight, no change in aircraft or flight crew, 737-300/500

Note: this will not be a discussion of weather, fatigue, or personal/emotional factors

OPPORTUNITIES FOR ERROR operational factors: Preflight

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SOPs typically describe• Preflight flow (memory)

- separate for CA and FO- may include optional checks (e.g., standby power check)

• Preflight checklist (card)- not intended as “read and do” list- verification of “killer items” in preceding flow

Manuals discuss (to varying degrees) • Documentation required• Dispatch Release (acquisition, duration, amendment)• Weather• Airport information• Alternates• Flight plan changes• Fuel considerations

PREFLIGHT: textbook version (any airline)

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PREFLIGHT checklist

Oxygen

Circuit Breakers

IRS selectors

Hydraulic pumps

xxx xxx xxx

Takeoff warning horn

Parking Brake

(10-15 items)

textbook version FIRST OFFICER

Obtain ATIS

Obtain clearance

Review paperwork

Prepare/review charts

Start PREFLIGHT flowXxxxx

Crew oxygen

Xx xx xx x Xxx Xxx

Air conditioning & Pressurization

FMC

Radios

Xxx

(20-30 items)

Finish PREFLIGHT flow

(Passenger count)

(Load Sheet)

Program FMC

Start PREFLIGHT checklist

PREFLIGHT checklist complete

PUSHBACK

CAPTAIN

Review paperwork

Sign flight release

Prepare/review charts

Start PREFLIGHT flowXxxxx

Crew oxygen

xxxxxxx

Fuel quantity

Xxx xxxx x Xxx

Xxxxxxxxxxxxxx Xxx

Parking brake

(20-30 items)

Finish PREFLIGHT flow

Review Load Schedule

Takeoff brief

Ask for PREFLIGHT checklist

MONITOR Flight Interphone

MONITOR Ground frequency

Company/Dispatch frequencyCabin & cockpit temp

Flight release

Passenger count

Load data Fuel

slip

FoodRest

Personal

Baggage Handlers

Push Back Crew

JumpseatRider(s)

Cabin Crew

MaintenanceCrew

Gate Crew

Passengers

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CAPTAIN

Review paperwork

Sign flight release

Prepare/review charts

Start PREFLIGHT flowXxxxx

Crew oxygen

xxxxxxx

Fuel quantity

Xxx xxxx x Xxx

Xxxxxxxxxxxxxx Xxx

Parking brake

(20-30 items)

Finish PREFLIGHT flow

Flight Release?

Fuel Slip?

Maintenance?

Load/W&B schedule?

Passenger count?

Review Load Schedule

Takeoff Brief

Ask for PREFLIGHT checklist

FIRST OFFICERObtain ATIS

Obtain clearance

Review paperwork

Prepare/review charts

Start PREFLIGHT flowXxxxx

Crew oxygen

Xx xx xx x Xxx Xxx

Air conditioning & Pressurization

Xxxxxxxxxxxxxx Xx

FMC

Radios

Xxx

(20-30 items)

Finish PREFLIGHT flow

(Passenger count)

(Load Sheet)

Complete programming FMC

Start PREFLIGHT checklist

PREFLIGHT checklist complete

PREFLIGHT checklist

Oxygen

Circuit Breakers

IRS selectors

Hydraulic pumps

xxx xxx xxx

Takeoff warning horn

Parking Brake

(10-15 items)

PUSHBACK

real life demands(compiled observations)

PDC unavailable

Inoperative item

Passenger count unavailableStill not picked up

no time, familiarity

Interruption

Interruption

Delay at gate

Ramp and/or Ground?

busy frequency

Flight plan/Departure runway change

Conduct exterior walk-around

no time, familiarity

New PDC

Still refueling

FO busy/behind

Load sheet unavailable

Request pax count

IRSs need 10 min for alignment

Takeoff brief

Call maintenance

Look for ops/gate agent

APU off for 2 min before off-loading

Defer programming FMC

Double-check charts

Resume checklist

Interruption

Inoperative item

Confirm Mx responded

Confirm Mx departed

Confirm resolution

Confirm logbook on board

Keep trying

Check charts

Communicate with company

Compute new performance #s

Re-program FMS

Re-program FMC

Check fuel quantity and pumps

Ask forChecklist

Re-brief

Re-flow trim & other settings

New flight release/PDC?Re-set MCP

Resume flow

Defer programming FMC

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CAPTAIN

Review paperwork

Sign flight release

Prepare/review charts

Start PREFLIGHT flowXxxxx

Crew oxygen

xxxxxxx

Fuel quantity

Xxx xxxx x Xxx

Xxxxxxxxxxxxxx Xxx

Parking brake

(20-30 items)

Finish PREFLIGHT flow

Flight Release?

Fuel Slip?

Maintenance?

Load/W&B schedule?

Passenger count?

Review Load Schedule

Takeoff Brief

Ask for PREFLIGHT checklist

FIRST OFFICERObtain ATIS

Obtain clearance

Review paperwork

Prepare/review charts

Start PREFLIGHT flowXxxxx

Crew oxygen

Xx xx xx x Xxx Xxx

Air conditioning & Pressurization

Hydraulics

FMC

Radios

(20-30 items)

Finish PREFLIGHT flow

(Passenger count)

(Load Sheet)

Complete programming FMC

Start PREFLIGHT checklist

PREFLIGHT checklist complete

PREFLIGHT checklist

Oxygen

Circuit Breakers

IRS selectors

Hydraulic pumps

xxx xxx xxx

Takeoff warning horn

Parking Brake

(10-15 items)

PUSHBACK

errors observed (ASRS incidents)

Omitted check of CBs: unable to start engine, return to gate, call Mx

skipped Hydraulics item - rudder found “stiff” on flight controls check: return to gate, call mx

Forgot to request updated PDC: take off without one

Fuel pumps deferred because still refueling, then missed on checklist: engine starvation in flight

Jumpseat rider interrupts checklist: forget to turn seat belt sign on

Interruptions during preflight: failed to program new departure

Missed aircraft not refueled/ insufficient fuel: discover in flight, return to airport

Defer looking for logbook when noticed it was missing: depart without it

Interruptions, workload, Defer notifying Mx of item noticed during walk-around: forgot to place call

Acars inop, defer getting load sheet: takeoff without

Interruptions, CA fails to notice FO programmed wrong flight plan

Distractions, improper setting of pressurization:-cabin altitude warning light in cruise

Distractions, omit throttles item: pushback with throttles open, damage to aircraft

CA failed to notice FO had programmed wrong squawk: confusion on climb out

Assumed other pilot had new PDC: depart without one

Omitted check of circuit breakers:landing gear horn at destination, go around

Omitted thorough check of CBs (flap): configuration warning horn at takeoff

Omitted careful review of charts, missed speed restriction on SID- speed violation

missed aircraft not refueled/ insufficient fuel: return to gate prior to taking off

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Non-linear structure• no predictable sequence of input events

e.g., passenger count may be delivered before/after FMS has been programmed

• no prescribed sequence of output events e.g., conduct departure brief before/after checklist

Flexible structure• no one prioritization scheme is prescribed

e.g., manage security concern vs. conduct flow

• no one scheme is applicable in every situation

Non-dependency of actions• step 2 does not always imply (previous ) step 1 has been accomplished

e.g., can calculate performance data before starting checklist if time permits

Concurrent activity• simultaneous involvement of many external “agents” (experts)

e.g., gate/operations agents, Ground, Maintenance, pushback crew, cabin crew, company

• lack of awareness about others’ responsibilities, stressors, pressures, language

• technically impossible not to pressure/interrupt one-another

PREFLIGHT: characteristics 1 of 2

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Inherent expectation that all systems are still “good to go” • just landed a “good” aircraft

Rhythm of ‘pushing ahead’ (even in the absence of real time pressure)

• reinforced by repetitive nature and philosophy of operations• “blurs” the details of actions among many preflights in a given workday• 63% of ‘Hurry Up’ errors originate at preflight (68% of which are joint errors)

Constant interruptions and distractions• defer/delay actions • interleave activities, often in new, never practiced ways• prioritize and juggle concurrent demands

Inadvertent deviations from SOPs or personal habits can occur and easily remain undetected by self and/or other pilot

PREFLIGHT: characteristics 2 of 2

OPPORTUNITIES FOR ERROR operational factors: Taxi Out

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FIRST OFFICERSet flaps

Request taxi clearance

Monitor radios

Receive taxi clearance

Acknowledge taxi clearance

Form mental picture of taxi route

Check for obstacles

Perform TAXI flow

Start TAXI checklist

Monitor radios

Monitor traffic

Monitor position on airport chart

TAXI checklist complete

Monitor CA and aircraft movement

Switch to Tower and monitor

Receive clearance

Acknowledge takeoff clearance

BEFORE TAKEOFF flow

Start checklist

Checklist complete

CAPTAIN Ask for flaps

Ask for taxi clearance

Monitor radios

Receive taxi clearance

Form mental picture of taxi route

Check for obstacles

Start taxiing

Perform TAXI flow

Ask for TAXI checklist

Monitor radios

Monitor traffic

Maintain positional and situational awareness

Monitor Tower

Receive clearance

BEFORE TAKEOFF flow

Ask for checklist

Line up with runway

Xxx

Xxx xx xxxxxx

"0" Fuel Weight

FMC

xx

Xx xx xxx xxxx

Xxxx xx

xxx

Xx xxxxxxxxxxx

Flaps

Xxx xx x x

xx

Xxx xxx x

X xx xxxx

Xxx

xxxxxxx

x

Takeoff Briefing

Xx xx xx

Recall

Xx x xxx

Transponder

xx

X xx xxxx xxxxxxx

TAKEOFF

real life demands(compiled observations)

MONITOR

TAXI

busy frequency

Delayed engine startDe-icing pad

Environmental conditions

no time

no time

no time, familiarityno time, familiarity

short taxi, no time

short taxi, no time

New/ Additional taxi instructions

Interruption

Ramp and/or Ground?

busy frequency

traffic, FO busy)

no time, familiarity

Change in takeoff runway

Just-in or new load data

Change in takeoff sequence

Program, set, verify

Extended taxi delay

Before/After Start Checklist

APU?

De-icing Checklist

Flaps before takeoff

Landinglights

Remember taxi instructionsId taxiways and turns

Remember to follow aircraftIdentify aircraft to follow

Remember to hold shortId correct place to hold short

Resume checklist

Double-check charts

Keep trying

Ask forChecklist

BriefNew runway

Consult charts

Accept/Plan/Requestnew runway

Keep head up/ outside

Calculate & reset Performance data

Inform Company (new #s, delays)

Resume checklist

Shoulderharness

Strobes

Check charts

Restart engine

Repeat checklists

RepeatChecklist?

FMC update

Shoulderharness

Radar?

Cross check with CA

Stow OPC

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FIRST OFFICERSet flaps

Request taxi clearance

Monitor radios

Receive taxi clearance

Acknowledge taxi clearance

Form mental picture of taxi route

Check for obstacles

Perform TAXI flow

Start TAXI checklist

Monitor radios

Monitor traffic

Monitor position on airport chart

TAXI checklist complete

Monitor CA and aircraft movement

Switch to Tower and monitor

Receive clearance

Acknowledge takeoff clearance

BEFORE TAKEOFF flow

Start checklist

Checklist complete

CAPTAIN Ask for flaps

Ask for taxi clearance

Monitor radios

Receive taxi clearance

Form mental picture of taxi route

Check for obstacles

Start taxiing

Perform TAXI flow

Ask for TAXI checklist

Monitor radios

Monitor traffic

Maintain positional and situational awareness

Monitor Tower

Receive clearance

BEFORE TAKEOFF flow

Ask for checklist

Line up with runway

Xxx

Xxx xx xxxxxx

"0" Fuel Weight

FMC

xx

Xx xx xxx xxxx

Xxxx xx

xxx

Xx xxxxxxxxxxx

Flaps

Xxx xx x x

xx

Xxx xxx x

X xx xxxx

Xxx

xxxxxxx

x

Takeoff Briefing

Xx xx xx

Recall

Xx x xxx

Transponder

xx

X xx xxxx xxxxxxx

TAKEOFF

errors observed (ASRS reports)

Forget to confirm tug clear - taxi into tug

Omit - overrun runway hold line

Mistook clearance to other aircraft for own - taxi without clearance

Confuse position - taxi into ditch

CA briefed and FO set wrong flaps for aircraft type - warning horn at takeoff

Busy starting engine & running delayed engine xlist and taxi xlist - runway incursion

Busy running checklist - force other aircraft to go around

Inadvertently hit flip-flop switch - delay

APU bleed source - lost both packs in flight - enter pre-stall buffet while troubleshooting

Omit or incorrectly set- warning horn at takeoff

Omitted checklist and has not restarted engine #1 - delay

Misunderstand tower instructions - taxi onto runway w/o clearance

Preoccupied with new departure clearance and packs-off operation and omit - aborted takeoff

New FO on IOE expected to hear “position and hold” - runway incursion

Squawk incorrectly set during preflight - rush and fail to notice error before takeoff

Fail to stop when lost - other aircraft had clearance canceled

Forgot to request new flight release after 1 hr ground stop

“Rushed” by aircraft pulling into same gate - omitted flaps - aborted takeoff

Forget to turn ignition switch on - overtemp engine

Congested frequency - delay - start taxi mistakenly assuming clearance rec’dAssumed only need to contact ramp - taxied onto active runway behind gate

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Aft Overhead

**

*

*Forward Overhead

Aft Overhead

FIRST OFFICER InstrumentCAPTAIN Instrument

Aft Electronic

Center Instrument

Forward Overhead

Mode Control Panel

Forward Electronic

ControlStand

TAXI OUT CA flow FO flow

CA, FO Checklist Checklist item

SEATBELT AND SHOULDER HARNESS

FLAPS

SEATBELT AND SHOULDER HARNESS

TAKEOFF BRIEFING

TAKEOFF BRIEFING

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VULNERABILITIES TO ERRORS cognitive factors

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INTERRUPTIONS & DISTRACTIONS

Interruption: event that causes (momentary) suspension of ongoing activity Distraction: event noticed and noted but remains ‘in background’ - pilot does not suspend task but mental processing may be impaired

Can be either expected or unexpected• nature and timing always unpredictable

Often underestimated because they are an integral part of everyday operations

• “there aren’t any” - “it’s all one big interruption”• lack of research and training on the topic

Contributing factors in 50% of air carrier major accidents of past decade Distractions: caused by non-related crew dialogue led FAA to impose ‘Sterile Cockpit Rule’ in 1981

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AUTOMATICITY

Highly practiced procedures become automatic (vs. controlled)• absence of conscious mental effort• desirable outcome of training

Advantages• allows fast, smooth execution of a task• frees up attention resources

Disadvantages• no conscious control of accuracy and timing• led (misled) by environmental cues

Automated procedures are vulnerable to omission when they are• interrupted• performed outside normal sequence or context

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DEFERRED TASKS 1 of 2

Forced deferment• interruptions (flight attendant interrupts departure brief) • environmental/operational factors (defer flaps at taxi in icing conditions)

Elected deferment• time pressure (defer consulting charts because pilot has fair idea of taxi route)• workload reduction (defer programming FMC until final load numbers)

Deferred task = intention to remember to do something in the future (prospective memory)

Cannot maintain delayed intentions in focal attention• must retrieve from memory when opportunity for execution arises• retrieval requires noticing some cue associated with intention• availability of cues and noticing cues is haphazard

Thus, memory lapses are commonplace

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DEFERRED TASKS 2 of 2

Remembering deferred intentions • e.g., call from Ground interrupts FO conducting preflight checklist

- physical cue available and practical (finger, card)• e.g., new load numbers during taxi, must inform company after takeoff

- physical cue not available or practical, but create artificial ‘trigger’ by tying deferred task to habitual future action (calling time off/out upon climb out)

• e.g., delivery of passenger count interrupts CA conducting a takeoff brief- interruption not noted, no ‘red flag’ and no cue is practical

Chances of remembering increase with use of cues as reminders

(ASRS 398323) During walkaround I discovered a discrepancy (open access panel) that required a call to maintenance. I finished the walkaround and intended to call maintenance… upon reentering the aircraft I allowed myself to become distracted with other problems and forgot to place the call. Aircraft would not pressurize after takeoff.

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SIDETRACKING

Attention drawn partly away from ongoing task e.g., in response to an interruption (to assess its importance, priority, and implications)

(ASRS 425830) I discovered the logbook was missing (during Preflight flow)... I allowed myself to get sidetracked during my search for it by FA concerns in the back. FO also realized it’s absence during preflight but decided to call it later... a jumpseat rider entered and interrupted the checklist at the point where absent logbook would have been noticed. Aircraft departed the airport without the aircraft logbook.

PREOCCUPATION

Attention drawn exclusively away from one task at the expense of another e.g., in response to

• a change in conditions affecting future task (weather, traffic)

• anxiety (emergency, new procedure)

(ASRS 455570) CA working with maintenance on APU problem. With ten minutes to go, FO discovers departure runway has changed, is reprogramming new departure and intends to review unfamiliar departure. CA pushing to start engine #1 before APU quits and to run checklists. Crew pushes back, APU fails again, so crew now has to coordinate a crossbleed start and get approval for dispatch without APU… both pilots failed to review restrictions on SID and company page, and exceed speed restriction on climb out.

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“COMPLACENCY”Blanket excuse for errors: “I’ll be more careful next time,” “Fatigue”

Just a label?

Real reasons• Appearance of normalcy

- repetitive nature of flight operations

- high probability of success

• Habit capture- virtually impossible to resist automatically performing a well-practiced, habitual task

- natural to be unable to put thought and effort into performing tasks that have become automatic

• Tempo of flows and checklists - inadvertently “fly through” checklists and procedures

• Assumptions- Assume other pilot has copied taxi instructions correctly

- Assume entire radio set up correctly when dialing in new frequency

- Assume no obstacles because Ground is sequencing all aircraft on taxiways (look but not see)

• Expectations- runway used in previous x number of takeoffs or on PDC

- approach typically used at this airport at this time of year

- type of aircraft usually flown

(ASRS 453640) FO set FMC at gate, I verified route and performance data, noted the cruise altitude he had set and checked the pressurization system. I did not crosscheck the cruise altitude with the PDC as is my usual practice. He had set everything up for FL310 while paperwork indicated FL350… I had relaxed my vigilance because the FO and I flew same aircraft in military and knew some of the same people. Contributing factors may be lower alertness due to early wake-up.

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TRIGGERS

Many actions rely on natural ‘triggers’• environmental cues (reset altimeter at specific altitude)

• preceding actions (brief approach after receiving ATIS)

• others’ actions (start checklist when PF asks for it)

Certain events disrupt presence of ‘triggers’, or remove them entirely• environmental factors (pushing back on one engine)

• addition/deletion of task (security brief)

• abnormal indication/situation (respond to FA’s concerns about a cabin situation)

• pressure (receive pushback clearance and proceed to start without ensuring cabin ready)

… In the meantime, events continue to occur in their normal sequence

Difficult to notice absence or disruption of triggers

Pilots devise their own ‘triggering’ strategies• finish After Start checklist, put hand on Flap lever

(ASRS 379824) At completion of pushback I set the parking brake, completed engine start and verbally released the pushback crew - they acknowledged. We completed the After Start checklist, received taxi clearance, and began to taxi. Just as we moved the aircraft, they ran into my visual area and signaled an emergency stop. I then realized that I had not received nor responded to an “all clear” signal. The problem occurred because an inordinately long time elapsed after verbally releasing the ground crew and when we normally receive a “clear” signal… during that time frame, which was 3 times longer than normal, I completed all checklists, got clearance, and forgot that I had not been given the “thumbs up’ signal.

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Opportunities for error in work environment

Vulnerabilities inherent in human cognitive abilities

Illustration using an NTSB incident report

Errors happen even to the most expert pilots - WHY?

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PREFLIGHT

case study

Auto-throttle and other problems on approach; maintenance notified

Upon arrival: CA inside to prepare return flight, FO outside for walk-aroundMaintenance starts 40 Full System check (involves movement of throttles)

TIME CAPTAIN FIRST OFFICER OTHER

Returns to cockpit Returns to cockpit Still conducting test

Finish tests, return airplane

Cockpit flow Cockpit flow

0:43” Before Start Engine check Starts checklist

0:58 “Before I forget, let’supdate…”

“Fuel Panel”

1:02” Agent: everything fixed?

1:02”-1:55” Discussion between Gate Agent and Flight Crew

1:55” “all right now, where werewe?”

“at IRSs” (prior to fuelpanel)

FMS setup

2:16” Chief pilot arrives

2:16”-5:44” Conversation between Chief Pilot and Flight Crew

5:44”-6:54” Discussion about FMS - momentary conversations with Gate Agent

6:54” Tug driver establishescontact by interphone

7:01 “Brakes released, checklist”

7:05” “Checked” “where were we, rudderpedals and seats, FMS?”

7:09” “closed” “thrust levers”

7:14”-7:52” Discussion about FMS

7:53” Resume checklists (Before Start, 5 min prior, Prior to pushback)

8:44” Call Ground for pushback Ground approves pushback

Pushback is initiated –Flight Crew continues to discuss FMS setup

9:57” “Cleared to start – all right,number one”

10:10” Conversation not relevant to engine startStart of second engine can be heard on CVR (with outverbal comment)

10:56” “engine anti-ice on”

Impact of fuselage with tow bar

Distraction

Good technique: resume checklist

prior to interruption

Interruption

Distraction

Interruptions

Interruption

Rushing through checklist: 2 challenges together

Interruption

Omits check(?) and response

Leads to step normally later in checklist

Preoccupation

Preoccupation

Interruption

Sidetrack: brings maintenance issue back to foreground

Distraction

Leads to step normally later

(“fuel panel” never responded to,7 other challenges never mentioned)

Automaticity:accept double challenge;1 response to 2 challenges

Automaticity, habit capture

Distraction

Expectation, assumption

Distraction

Defer starting preflight flowNYC01LA077Throttle check

Throttle check

Throttle check

Throttles not fully closed

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QuickTime™ and aGIF decompressorare needed to see this picture.

OPPORTUNITIES FOR AND VULNERABILITIES TO ERROR

IN EVERYDAY FLIGHT OPERATIONS

ATA/CRM ConferenceMARCH 2002

Loukia D. Loukopoulos

Human Factors Division, MS 262-4

NASA Ames Research Center

Moffett Field, CA 94035

650-604-2843

llouko@mail.arc.nasa.gov

QuickTime™ and aGIF decompressor

are needed to see this picture.