Flight time limitations: Flight engineers: airplanes

This regulation determines which flight time limitations apply to flight engineers based on crew composition.

When only one flight engineer is on board, that engineer must follow the standard flight time limits found in §§121.503 and 121.505, which are the same rules that apply to most flight crewmembers.

However, when the crew includes multiple flight engineers AND more than two pilots, the flight engineers follow the extended flight time limits in §121.509 instead of §121.505. Section 121.509 allows for longer duty periods when augmented crews are present.

This matters because it permits airlines to use flight engineers on longer flights when they have sufficient crew redundancy. The additional pilots and flight engineers allow for in-flight rest rotation, making extended operations feasible while maintaining safety. Flight engineers need to know which limitation applies to properly plan their duty periods and ensure regulatory compliance.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*