---
kind: "section"
citation: "14 C.F.R. § 91.403"
title: "14"
number: "91.403"
heading: "General."
url: "https://uscodex.org/cfr/14/91.403"
---

# §91.403. General.

- (a) The owner or operator of an aircraft is primarily responsible for maintaining that aircraft in an airworthy condition, including compliance with [part 39](/cfr/14/part39.md) of this chapter.
- (b) No person may perform maintenance, preventive maintenance, or alterations on an aircraft other than as prescribed in this subpart and other applicable regulations, including [part 43](/cfr/14/part43.md) of this chapter.
- (c) No person may operate an aircraft for which a manufacturer's maintenance manual or instructions for continued airworthiness has been issued that contains an airworthiness limitations section unless the mandatory replacement times, inspection intervals, and related procedures specified in that section or alternative inspection intervals and related procedures set forth in an operations specification approved by the Administrator under part [121](/cfr/14/part121.md) or [135](/cfr/14/part135.md) of this chapter or in accordance with an inspection program approved under [§ 91.409(e)](/cfr/14/91.409.md?p=e) have been complied with.
- (d) A person must not alter an aircraft based on a supplemental type certificate unless the owner or operator of the aircraft is the holder of the supplemental type certificate, or has written permission from the holder.

## Notes

### Amendments

[Docket 18334, 54 FR 34311, Aug. 18, 1989, as amended by Amdt. 91-267, 66 FR 21066, Apr. 27, 2001; Amdt. 91-293, 71 FR 56005, Sept. 26, 2006]

### Source

Source: Docket 18334, 54 FR 34311, Aug. 18, 1989, unless otherwise noted.

### Authority

Authority: 49 U.S.C. 106(f), 40101, 40103, 40105, 40113, 40120, 44101, 44111, 44701, 44704, 44709, 44711, 44712, 44715,44716, 44717, 44722, 44740, 46306, 46315, 46316, 46504, 46506-46507, 47122, 47508,47528-47531, 47534; Pub. L. 112-95, 126 Stat. 11; Pub. L. 114-190, 130 Stat. 615 (49 U.S.C. 44703 note); sec. 828, Pub. L. 118-63, 138 Stat. 1330 (49 U.S.C. 44703 note); articles 12 and 29 of the Convention on International Civil Aviation, 61 Stat. 1180.

### Amendments

[Docket 18334, 54 FR 34311, Aug. 18, 1989, as amended by Amdt. 91-267, 66 FR 21066, Apr. 27, 2001; Amdt. 91-293, 71 FR 56005, Sept. 26, 2006]