14 CFR § 33.53 - Engine system and component tests.

---
identifier: "/us/cfr/t14/s33.53"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "14 CFR § 33.53 - Engine system and component tests."
title_number: 14
title_name: "Aeronautics and Space"
section_number: "33.53"
section_name: "Engine system and component tests."
chapter_name: "FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
subchapter_number: "C"
subchapter_name: "AIRCRAFT"
part_number: "33"
part_name: "AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "49 U.S.C. 106(g), 40113, 44701, 44702, 44704."
regulatory_source: "Docket No. 3025, 29 FR 7453, June 10, 1964, unless otherwise noted."
cfr_part: "33"
---


# 33.53 Engine system and component tests.

(a) For those systems and components that cannot be adequately substantiated in accordance with endurance testing of § 33.49, the applicant must conduct additional tests to demonstrate that systems or components are able to perform the intended functions in all declared environmental and operating conditions.

(b) Temperature limits must be established for each component that requires temperature controlling provisions in the aircraft installation to assure satisfactory functioning, reliability, and durability.

[Doc. No. 3025, 29 FR 7453, June 10, 1964, as amended by Amdt. 33-26, 73 FR 48285, Aug. 19, 2008]