Threat and error management (TEM)
Threat and Error Management (TEM): how an unmanaged operational problem becomes an unsafe outcome, and how errors are reviewed.
Chain (AC 700-031 s.2.3(1)):
| Stage | Meaning | Cite |
|---|---|---|
| Threat | Event or error beyond the flight crew's control; adds operational complexity; must be managed to hold the margin of safety | s.2.3(1)(y) |
| Undesired Aircraft State (UAS) | Result of a mismanaged threat; aircraft position, condition, or attitude (including low-energy state) that reduces or eliminates the safety margin | s.2.3(1)(aa) |
| Unsafe Situation | Result of a further-mismanaged UAS; unacceptable reduction in the safety margin | s.2.3(1)(ab) |
- TEM briefing before flight: identify potential threats (ASL 3/2025).
- Just culture: review errors openly, without blame; ask what conditions allowed the error, not who is at fault (ASL 3/2025, runway incursions). Each error is a learning opportunity: finds the weakness before it repeats.
Trap: a Threat is outside crew control; the crew's own mismanaged response to it becomes the Undesired Aircraft State.
References
- AC 700-031 s.2.3(1)(y),(aa),(ab)
- ASL 3/2025