The Flight Safety Foundation has published best practices guidelines for implementing a policy allowing for controlled rest (CR) on the flight deck. It was developed by an industry Fatigue Countermeasures Working Group that includes fatigue safety managers from commercial aircraft operators; pilot union labor representatives; researchers and scientists from Clockwork Research, NASA Ames Research Center, and Washington State University; and fatigue and human performance research organizations.

Controlled rest is defined by ICAO as a “short sleep opportunity” that serves as a mitigation strategy in case of unexpected fatigue during flight. It is not to be used as a planned strategy to extend duty periods, but rather as a “safety net” to combat in-flight fatigue. Nevertheless, CR periods have yet to be approved by all national regulatory authorities.

The first CR procedures were introduced by airlines more than 20 years ago; however, this document, “Controlled Rest on the Flight Deck: A Resource for Operators,” purportedly provides the first complete review of the practice, along with an overview of current scientific research on napping, sleep inertia, and CR.

Other sections of the 25-page publication offer guidance for operators in deciding whether to introduce CR; how to implement, document, and review an effective CR procedure; how to monitor and continuously improve CR as part of a fatigue risk management program; and ICAO’s recommended procedures for CR.

According to the report, a recent survey of managers and flight crew at operators with a CR policy revealed the following: 90 percent said the practice has provided significant benefits for flight safety, 87 percent said CR has reduced fatigue-related performance decrements during critical phases of flight, and 83 percent said CR has reduced instances of uncontrolled napping.

However, some national regulators, including the FAA (per Advisory Circular 120-100), prohibit CR. Controlled rest was considered when the latest FAA flight and duty time rules were developed beginning in 2010, but it was excluded from the final regulations. CR is permitted for some or all operators in Australia, Canada, New Zealand, and most states in Europe.