14 CFR § 33.33 - Vibration.

---
identifier: "/us/cfr/t14/s33.33"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "14 CFR § 33.33 - Vibration."
title_number: 14
title_name: "Aeronautics and Space"
section_number: "33.33"
section_name: "Vibration."
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"
---


# 33.33 Vibration.

The engine must be designed and constructed to function throughout its normal operating range of crankshaft rotational speeds and engine powers without inducing excessive stress in any of the engine parts because of vibration and without imparting excessive vibration forces to the aircraft structure.