Task Analysis

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General Aviation Mission Task AnalysisHighly simplified. Adapted from HF students' GA IDEF0 model.4 June 2013

Task CommentsA0: Perform General Aviation Mission Flight mission phases (mission profile) A1: Perform Preflight A11: Develop Flightplan A12: Fuel Aircraft A13: Complete Interior Check A14: Complete Exterior Check A15: Load Passengers and/or Cargo A16: File Flight Plan A2: Depart A21: Activate Flight Plan A22: Start Engine A23: Taxi to Hold Point A24: Take Off A3: Fly Enroute A31: Climb Enroute A32: Cruise Enroute A33: Descend Enroute A4: Arrive A41: Perform Approach A42: Land A43: Taxi To Stop A44: Close Flight Plan A5: Perform Postflight A51: Perform Engine Shutdown Procedure A52: Complete Postflight Checklist A53: Secure Aircraft A54: Unload Passengers and/or Cargo A55: Update Logs

Task Analysis

Page 2

General Aviation Mission Task AnalysisHighly simplified. Adapted from HF students' GA IDEF0 model.4 June 2013

Task CommentsA0: Fly Aircraft Concurrent tasks during all operational phases A1: Maintain Situation Awareness A11: Maintain Location Awareness A12: Maintain Aircraft Systems Awareness A13: Maintain Weather Awareness A14: Maintain Terrain Awareness A15: Maintain Traffic Awareness A16: Maintain Destination Awareness A2: Communicate With ATC & Other Pilots Communicate A21: Request & Receive Clearance A22: Respond As Requested By ATC A23: Report As Requested By ATC A24: Coordinate With Other Pilots At Uncontrolled Airports A3: Navigate & Adapt Flight Plan Navigate A31: Compare Current Location To Destination A32: Determine Appropriate Heading To Destination A32: Estimate Time To Arrival A34: Adapt Flight Plan To Weather, Traffic, etc. A4: Configure Aircraft & Manage Systems Manage Systems A41: Configure Aircraft for Departure/Cruise/Descent/Landing A42: Manage Fuel System A43: Manage Electrical System A44: Manage Manage Hydraulic System A45: Manage Radio Navigation System A46: Manage Radio Communication System A5: Aviate – Control Aircraft Aviate A51: Control Altitude A52: Control Heading A53: Control Speed A6: Communicate With Passengers

1

OSU Task Management Research

IE 548, Cognitive Engineering

2

Cockpit Task Management (CTM) Research

CTM: Process by which pilots selectively attend to multiple, concurrent flight tasks to safely and effectively complete a flight.

Lockheed L1011

Boeing 777

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A Conceptual Framework For CTM

● Literature Review● Cockpit Resource Management (e.g., Lauber, 1986)● Human error in aviation (e.g, Nagel, 1988; Wiener, 1987; Ruffel-Smith, 1979)● Cognitive psychology (e.g., Navon & Gopher, 1979; Wickens, 1984)● Systems theory (e.g., Padulo & Arbib, 1979)

● A Normative Model of CTM● initiate tasks to achieve goals● assess status of all tasks● terminate completed tasks● prioritize remaining tasks based on

– importance:1. aviate2. navigate3. communicate4. manage systems

– urgency– other factors (?)

● allocate resources (attend) to tasks in order of priority

Funk, K.H. (1991). Cockpit Task Management: Preliminary Definitions, Normative Theory, Error Taxonomy, and Design Recommendations, The International Journal of Aviation Psychology, Vol. 1, No. 4, pp. 271-285.

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Determining the Significance of CTM:Accident Analysis

● CTM Error Taxonomy● Task Initiation: early / late / incorrect / lacking● Task Prioritization: incorrect● Task Termination: early / late / incorrect / lacking

● Method:● Reviewed 324 National Transportation Safety Board (NTSB) Aircraft Accident Reports

(1960 – 1989)● Developed pre-impact timelines, classified CTM errors

● Findings: 80 CTM errors in 76 (23%) of the accidents

Chou, C.D., D. Madhavan, and K.H. Funk (1996). Studies of Cockpit Task Management Errors, International Journal of Aviation Psychology, Vol. 6, No. 4, pp. 307-320.

CTM Error # Accidents% CTM

Accidents # CTM Errors% of All CTM

Errors

Task Initiation 35 46 35 44

Task Prioritization 24 32 24 30

Task Termination 21 28 21 26

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Determining the Significance of CTM:Incident Analysis

● Method:● Reviewed 470 Aviation Safety Reporting System (ASRS) incident reports:

– Controlled Flight Toward Terrain incidents– In-flight engine emergency incidents– Terminal flight phase incidents

● Identified concurrent tasks, classified CTM errors● Findings: 231 (49%) of the incidents involved CTM errors

Chou, C.D., D. Madhavan, and K.H. Funk (1996). Studies of Cockpit Task Management Errors, International Journal of Aviation Psychology, Vol. 6, No. 4, pp. 307-320.

Conclusion: CTM is a significant factor in flight safety.

CTM Error # Incidents% CTM

Incidents # CTM Errors% of All CTM

Errors

Task Initiation 137 59 145 42

Task Prioritization 133 58 122 35

Task Termination 83 36 82 23

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Understanding CTM:Incident Analysis

● Does cockpit automation level affect task performance?

● Method: ● Reviewed 420 NASA ASRS

incident reports– 210 advanced technology +

210 conventional technology ● large commercial transport

aircraft● 2 pilots● 1988-89, 1990-91, 1992-93

● Reviewed narratives● Constructed task models● Classified errors● Comparison with t-tests

● Findings:● Error rate higher for advanced

technology aircraft (p = 0.036)● Error rate decreasing (p = 0.032)

Task Prioritization Error Frequency

Total Errors by Submission Period

Adv

ance

d T

ech

nolo

gy

Tra

dit

iona

l T

ech

nolo

gy

Submission Period

1988-1989 13 7 20

1990-1991 11 5 16

1992-1993 4 3 7 Total Errors by

Aircraft Technology 28 15

Wilson, J. and K. Funk (1998). The Effect of Automation on the Frequency of Task Prioritization Errors on Commercial Aircraft Flight Decks: An ASRS Incident Report Study, Proceedings of the Second Workshop on Human Error, Safety, and System Development, Seattle, WA, April 1-2, 1998, pp. 6-16.

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Understanding CTM:Simulator Study

● What are the factors that affect task prioritization in the CTM process?

● Method: simulator study● Professional pilot participants● Difficult San Francisco approach scenarios● Task prioritization Challenge Probe Points (CPPs)● Stop sim or record & replay for interviews on CPPs:

“Why did you ...?”● Analysis with ANOVA

● Findings: Prioritization Factors1. Procedural compliance2. Task importance3. Task salience4. Task status5. Time/Effort requirements6. Task urgency

C A R M E

A N J E E

S K U N K

B O L D R

M E N L O

O A K V O R

S F O 2 8 R I L S

B i g S u r V O R

E 1 - C A R M E( S c e n a r i o E v e n t )

T u r n f r o m V 2 7 t o 3 3 1 R a d i a lD M E = 8 3 . 9

E 2 - D M E 4 2( A T C E v e n t )

V e c t o r a n d A l t . I n s t r u c t i o n sD M E = 4 2

E 3 - B O L D R( M a l f u n c t i o n E v e n t )

B u s T i e C o n t a c t o r ( M 4 )D M E = 3 4

E 4 - V e c t o r 3 6 0( A T C E v e n t )

V e c t o r i n s t r u c t i o nD M E = 2 5

E 5 - L o c a l i z e r( S c e n a r i o E v e n t )

L o c a l i z e r N e e d l e " S w i n g s "D M E = 1 7 . 6

E 6 - F i n a l( M a l f u n c t i o n E v e n t )

B o o s t P u m p F a i l u r e ( M 5 )D M E = 1 3

F l i g h t P a t h

S t u d y 1 B r a v o E x p e r i m e n t a l S c e n a r i o w i t h D a t a C o l l e c t i o n P o i n t s

S t a r t t u r n a b o u t 8 3 . 9 f r o m O A K

S p e e d = 3 0 0a l t = 1 0 , 0 0 0f r e q = 1 3 4 . 5

S p e e d = 2 1 0a l t = 8 0 0 0

f l a p s = 1a p p r o a c h / d e s c e n t c h e c k l i s t

a l t = 6 0 0 0

2 5 n m f r o m O A KS p e e d = 1 9 0

f l a p s = 5

S p e e d = 1 6 5f l a p s = 2 5

F i n a l D e s c e n t c h e c k l i s t

E 1 - S c e n a r i o E v e n tE 2 - A T C E v e n tE 3 - M a l f u n c t i o n E v e n tE 4 - A T C E v e n tE 5 - S c e n a r i o E v e n tE 6 - M a l f u n c i t o n E v e n t

3 6 0 °

3 2 5 °

D i r e c t i o n o f F l i g h t

Colvin, K., K. Funk, & R. Braune (2005). Task Prioritization Factors: Two Part-Task Simulator Studies, International Journal of Aviation Psychology, Vol. 15, No. 4, pp. 321–338.

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Improving CTM:Experimental Study (Training)

● Can task prioritization be trained?● APE Mnemonic: Assess, Prioritize, Execute● Simulator Experiment

● Licensed pilot participants● Independent variable: training (Descriptive,

Prescriptive, None/Control)● Dependent Variables

– Task Prioritization Error Rate– Prospective Memory Recall

● Flight – training / no training – flight● ANOVA of results●

–––––

Bishara, S. and K. Funk (2002). Training Pilots to Prioritize Tasks, Proceedings of the Human Factors and Ergonomics Society 46th Annual Meeting, Baltimore, MD, September 30-October 4, 2002, pp. 96-100.

Interaction Plot

Flight

Err

or

Rat

e

GroupControlDescriptivePrescriptive

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Pre Training Post Training

Prio

riti

zati

on E

rror

Rat

e

Control

Descriptive

Prescriptive

Interaction Plot

Flight

Mem

ory

Tas

ks

GroupControlDescriptivePrescriptive

0.5

0.6

0.7

0.8

0.9

1

Pre Training Post Training

Pros

pect

ive

Mem

ory

Perf

.

Prescriptive

Descriptive

Control

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Improving CTM:Experiment (System Comparison)

● Can CTM be facilitated by a cockpit aid?● AgendaManager (CTM aid) vs. EICAS (conventional pilot warning/alerting system)● Simulator Experiment

● Professional pilot participants● Independent Variable: Alerting (AMgr vs. EICAS)● Dependent Variables: CTM metrics● Flight 1 (EICAS/AMgr) – Flight 2 (AMgr/EICAS)● ANOVA of results

Funk, K. and Braune, R. (1999). The AgendaManager: A Knowledge-Based System to Facilitate the Management of Flight Deck Activities, SAE 1999-01-5536. 1999 World Aviation Congress, 19-21 October 1999, San Francisco, CA.

Dependent Variable AMgr EICAS sig.

Within subs. correct prioritization 100% 100% NS

Subs. fault correction time (sec) 19.5 19.6 NS

A/F programming time (sec) 7.9 5.9 NS

goal conflicts % corrected 100% 70% 0.10

goal conflict resolution time (sec) 34.7 53.6 0.10

Subs./Aviate correct prioritization 72% 46% 0.05

Mean # unsatisfactory tasks 0.64 0.85 0.05

% time all tasks satisfactory 65% 52% 0.05

Mean participant rating (-5 - +5) 4.8 2.5 0.05

Findings

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Operating Room Distractions & Interruptions

● Background● Anecdotal evidence for problem● Few scientific studies

● Research hypothesis: OR D&Is affect surgeon performance

● Experiment at OHSU● LapVR laparoscopic simulator● Simulated laparoscopic

cholecystectomy● 18 surgical residents● Realistic distractions & interruptions● Time & injury data

Feuerbacher, R., Funk, K., Hunter, J. Spight, D., Diggs, B. (in review). Realistic Distractions & Interruptions Impair Surgical Performance, Archives of Surgery. (Presented at Pacific Coast Surgical Association 2012 Annual Meeting.)

Results