Crew resource management: a simulator study comparing fixed versus formed aircrews.

BACKGROUND: Most airline and military transport planes are flown by crews that have been teamed together for a short amount of time before disbanding and becoming part of a different crew (formed crew concept). Some military operations use a fixed crew concept, pairing crewmembers together for an indefinite period. This research investigated the effect of crew formation policy on aircrew performance during missions in U.S. Air Force KC-135 (tanker) simulators. METHOD: The performance of fixed aircrews is compared to formed aircrews flying the same simulator mission scenario, which included an in-flight emergency. Cockpit resource management (CRM) behavioral data and error data were collected by trained observers for 17 crews (9 fixed and 8 formed). RESULTS: The results show that fixed crews committed more minor errors (4.4 per mission) than formed crews (2.6 per mission), t(14) = 2.32, p = 0.036. No differences were found concerning major errors or CRM behavioral indicators. CONCLUSIONS: The results suggest the possibility of a "familiarity decline," where aircrew performance declines when crewmembers become too familiar with each other and may affect flight safety.