You are using an unsupported browser. This web site is designed for the current versions of Microsoft Edge, Google Chrome, Mozilla Firefox, or Safari.
The Office of the Federal Register publishes documents on behalf of Federal agencies but does not have any authority over their programs. We recommend you directly contact the agency associated with the content in question.
If you have comments or suggestions on how to improve the www.ecfr.gov website or have questions about using www.ecfr.gov, please choose the 'Website Feedback' button below.
If you would like to comment on the current content, please use the 'Content Feedback' button below for instructions on contacting the issuing agency
Enhanced content is provided to the user to provide additional context.
This content is from the eCFR and is authoritative but unofficial.
Navigate by entering citations or phrases (eg: 1 CFR 1.1 49 CFR 172.101 Organization and Purpose 1/1.1 Regulation Y FAR).
Choosing an item from citations and headings will bring you directly to the content. Choosing an item from full text search results will bring you to those results. Pressing enter in the search box will also bring you to search results.
Background and more details are available in the Search & Navigation guide.
The in-page Table of Contents is available only when multiple sections are being viewed.
Use the navigation links in the gray bar above to view the table of contents that this content belongs to.
49 U.S.C. 106(f), 106(g), 40113, 44701, 44702 and 44704; Pub. L. 115-254, 132 Stat 3281 (49 U.S.C. 44903 note).
Docket No. 5066, 29 FR 18291, Dec. 24, 1964, unless otherwise noted.
This content is from the eCFR and may include recent changes applied to the CFR. The official, published CFR, is updated annually and available below under "Published Edition". You can learn more about the process here.
Subscribe to: 14 CFR 25.901
View the most recent official publication:
These links go to the official, published CFR, which is updated annually. As a result, it may not include the most recent changes applied to the CFR. Learn more.
Information and documentation can be found in our developer resources.
The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. The Electronic Code of Federal Regulations (eCFR) is a continuously updated online version of the CFR. It is not an official legal edition of the CFR.
Learn more about the eCFR, its status, and the editorial process.
(a) For the purpose of this part, the airplane powerplant installation includes each component that—
(1) Is necessary for propulsion;
(2) Affects the control of the major propulsive units; or
(3) Affects the safety of the major propulsive units between normal inspections or overhauls.
(b) For each powerplant—
(1) The installation must comply with—
(i) The installation instructions provided under §§ 33.5 and 35.3 of this chapter; and
(ii) The applicable provisions of this subpart;
(2) The components of the installation must be constructed, arranged, and installed so as to ensure their continued safe operation between normal inspections or overhauls;
(3) The installation must be accessible for necessary inspections and maintenance; and
(4) The major components of the installation must be electrically bonded to the other parts of the airplane.
(c) For each powerplant and auxiliary power unit installation, the applicant must comply with the requirements of § 25.1309, except that the effects of the following failures need not comply with § 25.1309(b)—
(1) Engine case burn-through or rupture,
(2) Uncontained engine rotor failure, and
(3) Propeller debris release.
(d) Each auxiliary power unit installation must meet the applicable provisions of this subpart.
[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-23, 35 FR 5676, Apr. 8, 1970; Amdt. 25-40, 42 FR 15042, Mar. 17, 1977; Amdt. 25-46, 43 FR 50597, Oct. 30, 1978; Amdt. 25-126, 73 FR 63345, Oct. 24, 2008; Doc. No. FAA-2022-1544, 89 FR 68734, Aug. 27, 2024]