Threat and Error Management (Strategies and Countermeasures)

TEM Strategies and Countermeasures

Strategies and Countermeasures are TEM tools used by flight crews as part of their normal operational duties. They are actions used by the crew to manage threats, errors and undesired aircraft states to reduce their impact on safety margins in flight operations. Countermeasures are divided into categories based on their source. "Hard" resources are provided by the aviation system and "soft" resources refer to crew contribution at the human level.

Hard Resources (systemic based )

  • Legislative controls (ICAO, CAA, FAA)
  • Aircraft Systems Design: Collision Avoidance Systems (TCAS/ACAS)
  • Operating procedures and practices (SOP's, checklists, briefings)
  • Training (maintain and develop expertise, improve crew coordination)

Soft Resources (personal and team strategies or tactics)

  • Planning countermeasures :
SOP Briefing
Interactive and operationally thorough briefing that meets SOP requirements in establishing points where actions are required.
Plans Stated
Operational plans and decisions adequately discussed to provide the crew with a shared understanding.
Workload Assignment
Roles and responsibilities defined and understood for normal and non-normal situations.
Contingency Management
Development of effective strategies to manage threats including anticipating their nature and consequences as well as allocation of resources to manage them.
  • Executing countermeasures :
Monitor and Cross-Check
Crew actively monitor and cross-check systems and each other.
Workload Management
Operational tasks are given correct priority to ensure primary flight duties are adequately managed, task fixation is avoided and workload capacities are not exceeded.
Automation Management
Adequate use of automation is applied to balance workload and situational requirements. The crew communicates and maintain shared awareness of automated conditions and execute effective recovery techniques when anomalies occur.
  • Review countermeasures :
Evaluation and Modification of Plans
Crew decisions are collectively analyzed to verify the existing plan is the best option.
Crew openly question and clarify current plans adopting an attitude where nothing is assumed correct or knowledge is complete and unchallengeable.
Critical information and solutions are posited with assertively and without hesitation.

(Merritt & Klinect, 2006[1]; Maurino, 2005[2]) .

LOSA - Line operations safety audit.

Dr. James Klinect from the university of Texas has come up with an innovative and creative way of determining an airline's "safety culture" by successfully implementing a program called LINE OPERATIONS SAFETY AUDIT. He defines the program as a "Cholestrol check" of the airline, enabling the management to recognise the most imminent threats their airlines face during their routine course of operations as well as the common errors that it's flight operations division commits.

This is accomplished by nominating pilots within the airline and training them to conduct safety audits by observing regular line flights from the supernumery seat in the cockpit. The LOSA inspector observes and recognises all the threats he notices during a given flight as well as the errors committed by the flight crew. He then develops a detailed report and sends his findings directly to the LOSA committe.

As one can see that it is imperative to gain the confidence of the pilots before conducting an exercise of this nature. Because any faith lost in the system may instill a fear factor amongst the flight crew about the punitive actions by the management in case of any errors committed. The crux of the exercise is to feel the pulse of the airline operations at its vulnerable best and not when the flight crew are alarmed and performing at an enhanced level. Hence all observations as conducted during non training flights.

The details of multiple audits are filtered and delabelled for anonymity and analysed by a group of experts including Dr. James Klinect and the findings of the report are forwarded back to the airline, which then itself analyses the reports and considers implementing new standards and procedures after taking into cognisance, the findings to better deal with its inherent threats and manage the errors within the organisation in order to nullify of reduce their impact on safety.

1. Merritt, A., & Klinect, J. (2006). Defensive Flying for Pilots: An Introduction to Threat and Error Management. The University of Texas Human Factors Research Project - The LOSA Collaborative
Retrieved on the 15th August, 2009 from
2. Maurino, D. (2005). Threat and Error Management (TEM): ICAO Canadian Aviation Safety Seminar (CASS) Vancouver, BC, 18-20 April 2005. Retrieved on the 15th August, 2009 from

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