14 CFR 91.105 : Aeronautics And Space (§ 1.1 To Parts 1311-1399) — (§ 60.1 To Parts 108-109) — Federal Aviation Administration, Department Of Transportation (Continued) (§ 60.1 To Parts 108-109) — Air Traffic And General Operating Rules (§ 91.1 To Parts 108-109) — General Operating And Flight Rules (§ 91.1 To Appendix G To Part 91) — Flight Rules (§ 91.101 To §§ 91.195-91.199) — General (§ 91.101 To §§ 91.148-91.149) — Flight crewmembers at stations.

(a) During takeoff and landing, and while en route, each required flight crewmember shall -

(1) Be at the crewmember station unless the absence is necessary to perform duties in connection with the operation of the aircraft or in connection with physiological needs; and

(2) Keep the safety belt fastened while at the crewmember station.

(b) Each required flight crewmember of a U.S.-registered civil aircraft shall, during takeoff and landing, keep his or her shoulder harness fastened while at his or her assigned duty station. This paragraph does not apply if -

(1) The seat at the crewmember's station is not equipped with a shoulder harness; or

(2) The crewmember would be unable to perform required duties with the shoulder harness fastened.