---
kind: "section"
citation: "14 C.F.R. § 121.251"
title: "14"
number: "121.251"
heading: "Engine accessory section diaphragm."
url: "https://uscodex.org/cfr/14/121.251"
---

# §121.251. Engine accessory section diaphragm.


Unless equivalent protection can be shown by other means, a diaphragm that complies with [§ 121.247](/cfr/14/121.247.md) must be provided on air-cooled engines to isolate the engine power section and all parts of the exhaust system from the engine accessory compartment.


## Notes

### Source

Source: Docket 6258, 29 FR 19202, Dec. 31, 1964, unless otherwise noted.

### Authority

Authority: 49 U.S.C. 106(f), 40103, 40113, 40119, 41706, 42301 preceding note added by Pub. L. 112-95, sec. 412, 126 Stat. 89, 44101, 44701-44702, 44705, 44709-44711, 44713, 44716-44717, 44722, 44729, 44732; 46105; Pub. L. 111-216, 124 Stat. 2348 (49 U.S.C. 44701 note); Pub. L. 112-95, 126 Stat. 62 (49 U.S.C. 44732 note); Pub. L. 115-254, 132 Stat. 3186 (49 U.S.C. 44701 note).