Threat and Error Management Model

1. Threat and Error Management Model Robert Helmreich Capt. Bruce Tesmer University of Texas Continental Airlines ATA CRM Conference Comair, Cincinnati September 21,1999

2. Applying TEMM to a ‘pilot error’ incident: Landing at the wrong airport

5. The Flight Scenario • Houston to Corpus Christi second leg of the first day of a trip that began in Newark • Captain was PF from Newark, FO to CRP • Captain was highly experienced check airman conducting IOE • CRP ATIS “..good, 6,000 broken 10 miles, wind 010, 10kts. Expect loc app to Rwy 31.” • Descent started early expecting VORTAC vectors to Rwy 31 localizer. ….. On autopilot until intercepting final approach course • After CRP Vortac, App Cont. gives vectors to, and clearance for intercepting localizer and “Cleared Approach.Rwy 31 Localizer”

6. The Scenario – continued • Turning final, the Capt sees the airport and reports to tower “Runway in sight.” • Crew has slowed and configured early to allow time to reach landing configuration and be stable by 500’ AGL. They are surprised runway so close. • A normal landing was completed but runway shorter than expected. Landing completed with 500’ remaining • There was no terminal, only hangers. Crew taxis off Rwy and realizes they are not at CRP • The call Tower which knows they have landed at Cabaniss

7. External Threats • Known • Threats • First day as crew • IOE being given • 1st leg in 737-300 round dial, 2nd in 737-500 EFIS • 1st EFIS leg for FO • FO only exposure to EFIS in Level 5 device • FO’s 1st trip to CRP • Capt had not been to CRP in 3 years & had never landed to North at CRP • Unexpected Threats • ATIS doesn’t mention 2000’ scattered cloud layer. Doesn’t warn about location of Cabaniss Field • A/C on autopilot, has problem intercepting localizer • Scattered 2,000’ cloud layer blocks fwd vision but allows ground contact for 5 miles • External • Error • ATC had localizer set to Rwy 13 for previous A/C doing training

8. Latent Systemic Threats • Regulatory: Cabniss Field located 6nm on Corpus localizer • Regulatory: no ATIS warning about Cabaniss on weekend • Regulatory: chart depiction hard to read • Regulatory: Cabaniss field layout looks like CRP • Regulatory: MSAW warning for Cabniss disabled • Regulatory: runway alignment (31) same as Corpus • Navy: allows racing events except special days (Mothers’ Day) • System: information on other near approaches to Cabaniss existed, but not available • Organizational: no mention of Cabaniss on10-7 page in manual • Professional: operational and professional pressure to make landing Crew Error

9. Proficiency Crew lacked knowledge about Cabaniss location Error Types Fail to Respond Error Responses Undesired State Error Outcomes Additional Error

10. Procedural Crew briefed and were flying ILS approach, did not check DME to confirm FAF Error Types Fail to Respond Error Responses Undesired State Error Outcomes Additional Error

11. Incident Decision Error Crew high & fast when lined up for Cabaniss but stable at 500’ chose riskier decision Error Types Fail to Respond Error Responses Undesired State Approach tp wrong airport Error Outcomes Fail to Respond Undesired Aircraft State Outcomes

12. Threat and Error Totals

13. System -- Organizational -- Professional Latent Systemic Threats External Threats Actions Error Action Outcomes Actions Final Outcome • External • Threats • Expected • Unknown External Error Threat Recognition and Error Avoidance Behaviors - Intentional Noncompliance -Procedural Communication Proficiency Operational Decision Fail to Respond Undesired Aircraft State Additional Error Inconsequential Mitigate Exacerbate Fail to Respond Recovery Additional Error Incident

14. System -- Organizational -- Professional 10 Latent Systemic Threats External Threats Actions Error Action Outcomes Actions Final Outcome • External • Threats • Expected -6 • Unknown -3 External Error 1 Threat Recognition and Error Avoidance Behaviors - 2 Intentional Noncompliance 1 -Procedural Communication 1 Proficiency 1- Operational Decision 3- Fail to Respond Undesired Aircraft State Additional Error Inconsequential Mitigate Exacerbate 1 Fail to Respond Recovery Additional Error 1 Incident

15. Conclusion • A short flight with a highly competent captain became very complex because of numerous latent systemic threats • These were compounded by external threat and error and crew errors • Any of a number of actions could have broken the incident sequence

16. About Latent Threats • Latent threats are highly variable. They can • exist for a long time • be based on tradition ‘We’ve always done it this way.’ • be associated with new technology • fail to appear as threats or seem to be based on good decisions • be difficult to resolve because corrective actions cross too many jurisdictions and no entity takes responsibility for corrective action • are often known by some but not communicated to others • frequently involve ‘local knowledge’ • Latent threats don’t show up in training

17. The Future • The identification of Latent Systemic Threats is essential to safety • Application of the model points to training needs and to latent threats that need to be modified • Safety, CRM, Training and Flight Ops need to coordinate to address threat and error management

18. CRM Countermeasures

19. External Threat and error Mental models Mental model check Cockpit Communication error CRM Countermeasures Possible Situation was high threat but not fully recognized

20. Conclusions • Crew faced a variety of external threats and error • Crew recognized and managed several threats • Latent Systemic Threats played a critical role • They can be addressed in CRM if identified • CRM countermeasures were available for error management • Mental models of ATC and Crew were understandable but led to misinterpretation of actions • A ‘Mental Model Check’ could have served as the critical countermeasure