An update on Lessons Learned: Designing Human Factors Research Products that Customers Will Use (not just human factors)

1
Concurrent Task Demands and Pilot Error in
Airport Surface Operations
Key Dismukes, Loukia Loukopoulos, Immanuel
Barshi Human Factors Research and Technology
Division NASA-Ames Research Center and U.S. Navy
Aerospace Experimental Psychology November
2003 FSF IASS, Washington D.C.
2
Consequences of Inadvertent Procedural Omissions

• LaGuardia (1994) MD-82 ran off runway end after
  high-speed rejected take-off
• NTSB Anomalous airspeed indications caused by
  failure to turn on pitot heat
• Detroit (1987) DC-9 crashed shortly after
  take-off
• NTSB Crew failed to set flaps/slats to take-off
  position
• Dallas (1988) B-727 crashed shortly after
  take-off
• NTSB Crew failed to set flaps/slats to take-off
  position
• ---------------------------------------------
  ---------------------------
• Houston (1996) DC-9 landed gear-up
• NTSB Hydraulic boost pump not set to high
  position

3
Were These Accidents Unique?
Not according to recent ASRS reports

• Rejected take-offs
• Anomalous airspeed indications (pitot heat not
  on)
• Configuration warning (flaps or trim not set)

Unnecessary costs and delays But for luck any of
these incidents might have become accidents
4
Why?

• Why would experienced crews forget a procedural
  step they normally perform day in and day out?
• Why fail to catch omissions with checklists?

5
An Ongoing NASA Research Project

• Carelessness not an adequate explanation
• Crews vulnerable to omissions when
• Interrupted or preoccupied with one of several
  concurrent tasks (Young, Dismukes, Sumwalt,
  1998).
• Deferring tasks out of normal sequence
  (Loukopoulos, Dismukes, Barshi, 2003).
• Vulnerability to error among experienced pilots
  largely driven by
• Characteristics of tasks performed
• Demands tasks place on human cognitive processes
• Operating environment
• Norms for actual line operations

6
Jumpseat Observation Study(Loukopoulos,
Dismukes, Barshi, 2003)

• Reviewed FOMs, observed line operations, analyzed
  ASRS, NTSB reports.
• All phases of flight focus today on preflight
  and taxi
• Discovered disconnect between FOM/training and
  actual line operations in area of task management.

7
Preflight - In theory (FOM)
CAPTAIN
FIRST OFFICER

• Obtain ATIS
• Obtain clearance
• Review paperwork
• Prepare/review charts
• (Passenger count)
• (Load Sheet)
• Program FMC
• Begin checklist

• Review paperwork
• Sign flight release
• Prepare/review charts
• Review Load Schedule
• Review FMC
• Takeoff brief

procedure
procedure
checklist
CLEARANCE
checklist
ENGINE START PUSHBACK
8
Depiction of Cockpit Task Management in
FOM/Training

• Linear task A task B task C in a fixed
  sequence.

9
Preflight - In theory (FOM)
CAPTAIN
FIRST OFFICER

• Obtain ATIS
• Obtain clearance
• Review paperwork
• Prepare/review charts
• (Passenger count)
• (Load Sheet)
• Program FMC
• Begin checklist

• Review paperwork
• Sign flight release
• Prepare/review charts
• Review Load Schedule
• Review FMC
• Takeoff brief

procedure
procedure
checklist
CLEARANCE
checklist
ENGINE START PUSHBACK
10
Depiction of Cockpit Task Management in
FOM/Training

• Linear task A task B task C in a fixed
  sequence.

• Controllable tasks are initiated by crew at
  their discretion.
• Predictable
• Information available to crew when needed.
• Individuals can communicate as needed.

11
Preflight - In theory (FOM)
CAPTAIN
FIRST OFFICER

• Obtain ATIS
• Obtain clearance
• Review paperwork
• Prepare/review charts
• (Passenger count)
• (Load Sheet)
• Program FMC
• Begin checklist

• Review paperwork
• Sign flight release
• Prepare/review charts
• Review Load Schedule
• Review FMC
• Takeoff brief

procedure
procedure
checklist
CLEARANCE
checklist
ENGINE START PUSHBACK
12
Taxi-out - In theory (FOM)
CAPTAIN
FIRST OFFICER

• Captain
• Start taxiing
• Ask for checklist
• Receive takeoff clearance

• First Officer
• Receive taxi clearance
• Start checklist
• Checklist complete
• Receive takeoff clearance

MONITOR Ground Company/Dispatch
MONITOR Ground Company
Taxi Clearance
MONITOR Captain taxiing
Takeoff Clearance
TAKEOFF
13
Depiction of Cockpit Task Management in
FOM/Training

• Linear task A task B task C in a fixed
  sequence.

• Controllable tasks are initiated by crew at
  their discretion.
• Predictable
• Information available to crew when needed.
• Individuals can communicate as needed.
• Overall picture flight operations are
  pilot- driven and under moment-to-moment control
  of crew.

14

• Review paperwork
• Sign flight release
• Prepare/review charts
• Review Load Schedule
• Review FMC

Preflight - the reality
CAPTAIN
FIRST OFFICER

• Obtain ATIS
• Obtain clearance
• Review paperwork
• Prepare/review charts
• (Passenger count)
• (Load Sheet)
• Program FMC
• Begin checklist

Ground/ Company/ Dispatch Frequencies
Interphone
Cabin Attendant
procedure
Gate Agent
ACARs / OPC
procedure
procedure
checklist
CLEARANCE
checklist
ENGINE START PUSHBACK
15

• Review paperwork
• Sign flight release
• Prepare/review charts
• Review Load Schedule
• Review FMC

Preflight - the reality
CAPTAIN
FIRST OFFICER

• Obtain ATIS
• Obtain clearance
• Review paperwork
• Prepare/review charts
• (Passenger count)
• (Load Sheet)
• Program FMC
• Begin checklist

Ground/ Company/ Dispatch Frequencies
Interphone
Cabin Attendant
procedure
Gate Agent
ACARs / OPC
procedure
procedure
checklist
CLEARANCE
checklist
ENGINE START PUSHBACK
16
Taxi-out - the reality
CAPTAIN
FIRST OFFICER

• Start taxiing
• Ask for checklist
• Receive takeoff clearance

• Receive taxi clearance
• Start checklist
• Checklist complete
• Receive takeoff clearance

MONITOR Ground//Dispatch
MONITOR Ground/Company
Taxi Clearance
MONITOR Captain taxiing
Takeoff Clearance
TAKEOFF
17
Line Observations Reveal a Different Story

• Normal line operations are quite dynamic

• Each pilot must juggle several tasks
  concurrently.
• Crews are frequently interrupted.
• External demands arrive at unpredictable moments.
• Conditions sometimes force task elements to be
  performed out of normal sequence.

18
Line Observations Reveal a Different Story

• Normal line operations are quite dynamic

• Each pilot must juggle several tasks
  concurrently.
• Crews are frequently interrupted.
• External demands arrive at unpredictable moments.
• Conditions sometimes force task elements to be
  performed out of normal sequence.

• Crews must at times struggle to maintain control
  of the timing and sequence of their work tasks.
• Little guidance or training.

19
Conflict Between Theory and Reality

• FOM is a powerful tool for safety by providing
• Operational reality disrupts ideal execution of
  procedures

• Explicit description of how each task is to be
  performed
• Standardization across crews
• Checklists and checking procedures

20
So What?

• Pilots become accustomed to concurrent task
  demands, interruptions, distractions and
  disruptions.
• However these situations substantially increase
  vulnerability to error, especially omission of
  critical procedural steps.

21
Sample of Preflight errors
CAPTAIN
FIRST OFFICER

• Obtain ATIS
• Obtain clearance
• Review paperwork
• Prepare/review charts
• (Passenger count)
• (Load Sheet)
• g
• Program FMC

• Review paperwork
• Sign flight release
• Prepare/review charts
• Review FMC
• Takeoff brief
• Ask for checklist

CLEARANCE
ENGINE START PUSHBACK
22

• Start taxiing
• Ask for checklist
• Receive takeoff clearance

Sample of Taxi-out errors
CAPTAIN
FIRST OFFICER

• Receive taxi clearance
• Start checklist

• TAKEOFF

23
Why So Vulnerable to These Errors?
24
Why So Vulnerable to These Errors?

• Brain has two ways of processing information to
  perform tasks
• Cockpit tasks vary from requiring mainly
  controlled processing to being largely automatic.

• 1) Controlled processing
• Corresponds to conscious attention
• Slow, serial, and effortful low capacity
• Required for tasks with novel aspects

• 2) Automatic processing
• Fast, minimal effort, high capacity
• Develops with extensive practice of habitual
  procedure
• Requires minimal conscious supervision

25
Automatic processing has enormous advantages but
also has serious vulnerabilities

26
Aft Overhead
Aft Overhead
CA flow FO flow
Checklist item


PREFLIGHT Flow (B737-300 - as trained)


Forward Overhead
Forward Overhead





Mode Control Panel


Mode Control Panel



First Officer Instrument
Captain Instrument

Center Instrument
Center Instrument


Captain Instrument
First Officer Instrument




Forward Electronic
Forward Electronic


Control Stand
Control Stand




Aft Electronic

Aft Electronic


Logbook/Gear Pins
Logbook/Gear Pins
27
Vulnerabilities of Automatic Processing

• If procedural flow is interrupted, chain is
  broken.
• Pause prevents one step from triggering the next.

• Initiation of automatic process depends on
  receiving signal or noticing a cue in the cockpit
  environment.
• If signal does not occur, individual is not
  prompted to initiate procedure.

28
Vulnerabilities of Automatic Processing

• If procedural flow is interrupted, chain is
  broken.
• Pause prevents one step from triggering the next.

• Initiation of automatic process depends on
  receiving signal or noticing a cue in the cockpit
  environment.
• If signal does not occur, individual is not
  prompted to initiate procedure.
• Highly practiced procedures and checklists tend
  to develop look without seeing automatic
  responses.

• High workload and/or rushing prevent conscious
  supervision of automatic processes
  exacerbates vulnerability.

29
Vulnerability to Errors of Omission Can Be Reduced

• 1) Actions airline operations and
  training departments can take
• 2) Actions individual pilots can take

30
Ways airlines Can Reduce Vulnerabilities

• Analyze actual line ops write procedures to
  minimize opportunities for disruptions.

• Avoid floating procedural items allowed to be
  performed at varying times.
• Anchor critical items (e.g., setting takeoff
  flaps) to distinct step that cannot be forgotten
  (e.g., before start of taxi).

31
Ways airlines Can Reduce Vulnerabilities

• Analyze actual line ops write procedures to
  minimize opportunities for disruptions.

• Avoid floating procedural items allowed to be
  performed at varying times.
• Anchor critical items (e.g., setting takeoff
  flaps) to distinct step that cannot be forgotten
  (e.g., pushback).
• Analyze actual fleet norms for how checklists
  are executed and bottom-lines observed.
• LOSA

32
Ways airlines Can Reduce Vulnerabilities

• Analyze actual line ops write procedures to
  minimize opportunities for disruptions.

• Avoid floating procedural items allowed to be
  performed at varying times.
• Anchor critical items (e.g., setting takeoff
  flaps) to distinct step that cannot be forgotten
  (e.g., pushback).
• Analyze actual fleet norms for how checklists
  are executed and bottom-lines observed.
• LOSA
• Train with realistic concurrent task demands

33
Ways Pilots Can Reduce Vulnerability

• Being aware of vulnerability reduces threat.
• Especially vulnerable when head-down,
  communicating, searching for traffic, or managing
  abnormals.

• When interrupted or deferring a task
• Pause to encode intention to resume
• Create conspicuous cue as reminder
• Develop habit of deliberate execution of
  procedures and checklists to allow controlled
  supervision of habitual responses.
• Avoid rushing.

34
Ways Pilots Can Reduce Vulnerability

• Being aware of vulnerability reduces threat.
• Especially vulnerable when head-down,
  communicating, searching for traffic, or managing
  abnormals.

• When interrupted or deferring a task
• Pause to encode intention to resume
• Create conspicuous cue as reminder
• Develop habit of deliberate execution of
  procedures and checklists to allow controlled
  supervision of habitual responses.
• Avoid rushing.

• Pause at critical junctures to review.

• Schedule / reschedule activities to minimize
  concurrent task demands (e.g., brief before TOD).

• Treat monitoring as essential task (Sumwalt).

35

• For further information
• http//human-factors.arc.nasa.gov/ihs/flightcognit
  ion/
• This work is supported by NASAs Airspace
  Systems Program and by the FAA (AFS-230), Dr.
  Eleana Edens, program manager.