Airline Pilot Terminology Explained: Flight Time and Duty Time Limitations

In the course of learning about how to become an airline pilot, you hear a lot of phrases that are not self-explanatory. Since you will definitely have to learn and use these concepts I thought I would explain a few of them. Flight Time and Duty Time are two phrases that mean something different to a Part 121 Airline Pilot then they might to the average General Aviation Pilot for example.

Flight time and duty time limitations for airline pilots are laid out in Part 121 of the Federal Aviation Regulations. The FAA flight time limitations for commercial pilots are as follows:

• 8 hours between required rest periods.
• 30 hours in any 7 consecutive days.
• 100 hour in any calendar month.
• 1000 hours in a calendar year.

8 hours between required rest periods is the hardest of the limitations to understand. The required rest can change depending on how many hours are actually flown in a 24 hour period. By regulation, a pilot can only be SCHEDULED to fly 8 hours in any 24 consecutive hours. Now, if because of delays beyond the Airline’s control, the 8 hours are exceeded, the pilot can complete the flying assignment, but they will need additional rest before another assignment is accepted. The FAA rest requirements are as follows:

• Scheduled for less than 8 hours = 9 hours of consecutive rest.
• If you end up flying more than 8 hours but less than 9 hours = 10 consecutive hours of rest.
• If you end up flying more than 9 hours = 11 hours of consecutive rest.

The 8 hour limitation is not often exceeded, but is does happen due to a variety of problems that may be encountered by an airline crew.

For airline pilots, there are two different types of times we must be cognizant of each day. One is the flight time the FAA requires us to keep track of for the limits discussed above. We call this actual flight time Block Time, and it is what we record in our logbooks. The other figure we should be conscious of is what we call Pay Credit, which is the amount of time that we will be paid for. Pay Credit is often more than the actual flight time for several reasons (and usually has to do with a Pilot’s union contract) and is what our pay is based upon.

The last “Time” that we must keep close track of is Duty Time. Duty time is the period between the time we check in at the airport to work, and the time which we check out for the day. The FAA allows us to be on duty for a maximum of 16 hours. The difference between a normal job and flying for the airlines is that a pilot may be scheduled to receive 8 hours of Pay Credit in a day, but it may occasionally take us 16 hours of Duty Time to get it if you include the time we are waiting at the airport between flights.

Keeping track of the different categories of “Time” is an important task for airline pilots because we need to stay in compliance with the FAA’s limitations while we make sure that we are paid correctly. It is quite different from the challenges of punching a time clock, but it can be easily mastered once you do it for a while.