Legal Interpretations
Dickson 2011
Summary
The Question
Under 14 CFR 121.503(b), how much rest must each of three pilots receive after a nine-hour supplemental flight on which each spends six hours on the flight deck?
Background
A requester posed a hypothetical: a Part 121 supplemental carrier schedules a nine-hour flight in an airplane certificated for two pilots, with three pilots each on the flight deck six hours and resting off it three hours.
The FAA’s Interpretation
At least 16 hours each before any further duty. The FAA interprets "flown" in 14 CFR 121.503(b) to cover the entire time a pilot who serves as a flight crewmember is on the airplane, not just flight deck time, so each pilot has flown 9 hours, more than eight hours in 24 consecutive hours.
- Requester
- Dickson
- Issued
- January 4, 2011
- Subject
- Flight & Duty Time
Regulations Cited
Page 1
U.S. Department
of Transportatlon
federal Aviation
Administration
JA:~ 4 2011
Scott Dickson
Dear Mr. Dickson,
Office of the Chief Counsel 800 Independence Ave .. S.W.
Washington, D.C. 20591
This is in response to your December 13, 2010, e-mail requesting a legal interpretation regarding the application of 14 C.F.R. 121.503(b) to the following hypothetical scenario. In your hypothetical scenario, a supplemental air carrier operating under Part 121 schedules a flight in a plane certificated for two pilots. The flight is scheduled as a nine-hour flight. The flightcrew includes three pilots each of whom will be on the flight deck for six hours during the flight and resting off the flight deck for three hours of the flight. Given this hypothetical scenario, your e-mail asks how much rest the operator would have to give each of the pilots after the flight pursuant to the provisions of§ 121.503(b). Section 121.503(b) applies to supplemental air operations, and it requires that"[e ]ach pilot who has flown more than eight hours during any 24 consecutive hours must be given at least 16 hours of rest before being assigned to any duty with the certificate holder." In situations in which a pilot is put on an airplane to serve as a flight crewmember at some point between origin and destination, the FAA has interpreted the phrase "flown" in § 121.503(b) as encompassing the entire time that the pilot is on the airplane and not simply the time that the pilot is on the flight deck. See Aug. 27, 1997 Letter to Timothy D. Miller from Donald Byrne, Assistant Chief Counsel.
Applying this interpretation to your example, since each of the pilots is going to be a flight crewmember at some point during the flight, each pilot will have "flown" the entire 9 hours of the flight regardless of how long he or she is off the flight deck. See id Therefore, each of these pilots will have flown over eight hours in a 24-consecutive-hour period and§ 121.503(b) would then require that each pilot receive 16 hours of rest before being assigned to any further duty with the certificate holder. See 14 C.F.R. 121.503(b).
Page 2
We appreciate your patience and trust that the above responds to your concerns. If you need further assistance, please contact my staff at (202) 267-3073. This response was prepared by Alex Zektser, Attorney, Regulations Division of the Office of the Chief Counsel, and coordinated with the Air Transportation Division of Flight Standards Service.
Sincerely,
R~t~er~r-Assistant Chief Counsel for Regulations, AGC-200
Regulations Referenced
Snapshot retrieved August 6, 2026.