14 CFR · Part 121
14 CFR § 121.509
Flight time limitations: Four pilot crews: airplanes.
(a)
No certificate holder conducting supplemental operations may schedule a pilot—
(1)
For flight deck duty in an airplane that has a crew of four pilots for more than eight hours in any 24 consecutive hours; or
(2)
To be aloft in an airplane that has a crew of four pilots for more than 16 hours in any 24 consecutive hours.
(b)
No pilot of an airplane that has a crew of four pilots may be on duty for more than 20 hours in any 24 consecutive hours.
Referenced By
Interpretations of This Section (10)
Documents that cite this section, found in their catalog metadata or text. Listed by date, not by significance.
Reflects the eCFR edition current as of September 29, 2026. Retrieved from ecfr.gov on October 16, 2026.
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