14 CFR § 35.37 - Fatigue limits and evaluation.

---
identifier: "/us/cfr/t14/s35.37"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "14 CFR § 35.37 - Fatigue limits and evaluation."
title_number: 14
title_name: "Aeronautics and Space"
section_number: "35.37"
section_name: "Fatigue limits and evaluation."
chapter_name: "FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
subchapter_number: "C"
subchapter_name: "AIRCRAFT"
part_number: "35"
part_name: "AIRWORTHINESS STANDARDS: PROPELLERS"
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(f), 106(g), 40113, 44701-44702, 44704."
regulatory_source: "Docket No. 2095, 29 FR 7458, June 10, 1964, unless otherwise noted."
cfr_part: "35"
---


# 35.37 Fatigue limits and evaluation.

This section does not apply to fixed-pitch wood propellers of conventional design.

(a) Fatigue limits must be established by tests, or analysis based on tests, for propeller:

(1) Hubs.

(2) Blades.

(3) Blade retention components.

(4) Components which are affected by fatigue loads and which are shown under § 35.15 to have a fatigue failure mode leading to hazardous propeller effects.

(b) The fatigue limits must take into account:

(1) All known and reasonably foreseeable vibration and cyclic load patterns that are expected in service; and

(2) Expected service deterioration, variations in material properties, manufacturing variations, and environmental effects.

(c) A fatigue evaluation of the propeller must be conducted to show that hazardous propeller effects due to fatigue will be avoided throughout the intended operational life of the propeller on either:

(1) The intended airplane by complying with § 23.2400(c) or § 25.907 of this chapter, as applicable; or

(2) A typical airplane.

[Amdt. 35-8, 73 FR 63348, Oct. 24, 2008, as amended by Doc. FAA-2015-1621, Amdt. 35-10, 81 FR 96700, Dec. 30, 2016]