FDP or Flight Duty Period
Before talking about Commander’s Discretion, we must quickly discuss FDP. FDP or Flight Duty Period (FDP) refers to the time from when a flight crew member is required to report for duty, which includes a flight or series of flights, and ends when the aircraft finally comes to rest and the engines are shut down at the end of the last flight on which they are a crew member. This is a basic definition and you will find your airline’s specific definition in Operation’s Manual Part A (OMA). Each airline will have slightly different definitions, e.g. how long before departure should a crew member report? Does positioning count towards FDP?
FDP has a maximum limit to prevent fatigue. In Europe, these limits are set by EASA (ORO.FTL.205), however, airlines CAN implement more restrictive conditions. Easyjet uses stricter FDPs(i.e. fewer hours on FDP due to union agreements). British Airways and Ryanair etc. operate towards full EASA limits. These considerations can sometimes form part of how much a pilot earns.
Commander’s or Captain’s Discretion
CAA regulations allow for an extension of the FDP under the commander’s discretion in unforeseen and unknown circumstances that occur at or after the reporting time. The time when people turn up for work. This rule is designed to provide flexibility in operations without compromising safety.
The commander may extend the FDP by up to 2 hours on short-haul flights. However, this is not a decision to be taken lightly. The commander must consider the current state of the crew, including any signs of fatigue, the nature of the unforeseen circumstances, and the potential impact on flight safety. The commander must also take into account the need for an adequate rest period following the extended FDP. On this note, the Commander can additionally use their discretion to extend a crew member’s rest. Conversely, they can also reduce rest.
An example of using the commander’s discretion to extend the FDP could be a situation where the flight is delayed due to unexpected weather changes at the home airport whilst downroute. Suppose the weather is forecasted to improve within a reasonable time. In that case, the commander may decide to extend the FDP to allow for the flight to proceed to the home base rather than diverting to an alternate airport or cancelling the flight and being stuck downroute.
Can any crew member decide if they want to go into discretion?
It’s important to note that the use of the commander’s discretion to extend the FDP is solely the commander’s decision. While the commander may seek input from other crew members, the final decision rests with the commander. The commander must judge if each member is “fit” to fly. Crucially, will they be fit to fly throughout the remaining duty? A common misconception by the crew is they will say phrases like “I’m not going into discretion”. This is a misunderstanding as it’s not the crew’s decision. The crew member is either fit to operate or not.
This information is then used by the commander, and the commander only to make an informed decision. This is because the commander has the ultimate responsibility for the safety of the flight. The commander’s discretion is not a committee decision, nor is it a decision that can be made by ground-based personnel. It is a decision that is made by the commander, based on their assessment of the situation, their experience, and their judgment.
I’ve gone into discretion approximately 10 times during my career and each time, it is not a decision to be taken lightly. Crewing and other ground-based staff WILL try and pressure crews to “keep the show on the road”. We must remember we are in a safety-related role and the buck stops with us. If you are not fit, tell your Captain and give them all the information they need to make an informed decision.