The Flight Duty Period (FDP) is a specific timeframe that begins when flight or cabin crew members report for duty. This period includes at least one flight and ends when the aircraft comes to a complete stop, with the engines shut down after the last flight. According to ICAO Annex 6, the FDP encompasses various tasks performed by crew members. These tasks can occur before a flight segment or between flights without requiring an intervening rest period. Examples of these tasks include deadhead transportation, training in an aircraft or flight simulator, and airport standby reserve. To reduce fatigue risks, there are two key limitations in place: the maximum duration of the FDP and the minimum duration of rest before the next FDP. The maximum duration aims to ensure that crew members do not experience performance issues due to fatigue. Meanwhile, the minimum rest period ensures that they start their next FDP feeling fully rested. Local regulations define the maximum duration of an FDP, such as 14 CFR Part 117 in the USA and Regulation 83/2014 in the EU.
