Collapse to view only § 25.4 - Definitions.
- § 25.1 - Applicability.
- § 25.2 - Special retroactive requirements.
- § 25.3 - Special provisions for ETOPS type design approvals.
- § 25.4 - Definitions.
- § 25.5 - Incorporations by reference.
§ 25.1 - Applicability.
(a) This part prescribes airworthiness standards for the issue of type certificates, and changes to those certificates, for transport category airplanes.
(b) Each person who applies under Part 21 for such a certificate or change must show compliance with the applicable requirements in this part.
§ 25.2 - Special retroactive requirements.
The following special retroactive requirements are applicable to an airplane for which the regulations referenced in the type certificate predate the sections specified below—
(a) Irrespective of the date of application, each applicant for a supplemental type certificate (or an amendment to a type certificate) involving an increase in passenger seating capacity to a total greater than that for which the airplane has been type certificated must show that the airplane concerned meets the requirements of:
(1) Sections 25.721(d), 25.783(g), 25.785(c), 25.803(c)(2) through (9), 25.803 (d) and (e), 25.807 (a), (c), and (d), 25.809 (f) and (h), 25.811, 25.812, 25.813 (a), (b), and (c), 25.815, 25.817, 25.853 (a) and (b), 25.855(a), 25.993(f), and 25.1359(c) in effect on October 24, 1967, and
(2) Sections 25.803(b) and 25.803(c)(1) in effect on April 23, 1969.
(b) Irrespective of the date of application, each applicant for a supplemental type certificate (or an amendment to a type certificate) for an airplane manufactured after October 16, 1987, must show that the airplane meets the requirements of § 25.807(c)(7) in effect on July 24, 1989.
(c) Compliance with subsequent revisions to the sections specified in paragraph (a) or (b) of this section may be elected or may be required in accordance with § 21.101(a) of this chapter.
§ 25.3 - Special provisions for ETOPS type design approvals.
(a) Applicability. This section applies to an applicant for ETOPS type design approval of an airplane:
(1) That has an existing type certificate on February 15, 2007; or
(2) For which an application for an original type certificate was submitted before February 15, 2007.
(b) Airplanes with two engines. (1) For ETOPS type design approval of an airplane up to and including 180 minutes, an applicant must comply with § 25.1535, except that it need not comply with the following provisions of Appendix K, K25.1.4, of this part:
(i) K25.1.4(a), fuel system pressure and flow requirements;
(ii) K25.1.4(a)(3), low fuel alerting; and
(iii) K25.1.4(c), engine oil tank design.
(2) For ETOPS type design approval of an airplane beyond 180 minutes an applicant must comply with § 25.1535.
(c) Airplanes with more than two engines. An applicant for ETOPS type design approval must comply with § 25.1535 for an airplane manufactured on or after February 17, 2015, except that, for an airplane configured for a three person flight crew, the applicant need not comply with Appendix K, K25.1.4(a)(3), of this part, low fuel alerting.
§ 25.4 - Definitions.
(a) For the purposes of this part, the following general definitions apply:
(1) Certification maintenance requirement means a required scheduled maintenance task established during the design certification of the airplane systems as an airworthiness limitation of the type certificate or supplemental type certificate.
(2) Significant latent failure is a latent failure that, in combination with one or more specific failures or events, would result in a hazardous or catastrophic failure condition.
(b) For purposes of this part, the following failure conditions, in order of increasing severity, apply:
(1) Major failure condition means a failure condition that would reduce the capability of the airplane or the ability of the flightcrew to cope with adverse operating conditions, to the extent that there would be—
(i) A significant reduction in safety margins or functional capabilities,
(ii) A physical discomfort or a significant increase in flightcrew workload or in conditions impairing the efficiency of the flightcrew,
(iii) Physical distress to passengers or cabin crew, possibly including injuries, or
(iv) An effect of similar severity.
(2) Hazardous failure condition means a failure condition that would reduce the capability of the airplane or the ability of the flightcrew to cope with adverse operating conditions, to the extent that there would be—
(i) A large reduction in safety margins or functional capabilities,
(ii) Physical distress or excessive workload such that the flightcrew cannot be relied upon to perform their tasks accurately or completely, or
(iii) Serious or fatal injuries to a relatively small number of persons other than the flightcrew.
(3) Catastrophic failure condition means a failure condition that would result in multiple fatalities, usually with the loss of the airplane.
(c) For purposes of this part, the following failure conditions in order of decreasing probability apply:
(1) Probable failure condition means a failure condition that is anticipated to occur one or more times during the entire operational life of each airplane of a given type.
(2) Remote failure condition means a failure condition that is not anticipated to occur to each airplane of a given type during its entire operational life, but which may occur several times during the total operational life of a number of airplanes of a given type.
(3) Extremely remote failure condition means a failure condition that is not anticipated to occur to each airplane of a given type during its entire operational life, but which may occur a few times during the total operational life of all airplanes of a given type.
(4) Extremely improbable failure condition means a failure condition that is not anticipated to occur during the total operational life of all airplanes of a given type.
§ 25.5 - Incorporations by reference.
(a) The materials listed in this section are incorporated by reference in the corresponding sections noted. These incorporations by reference were approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. These materials are incorporated as they exist on the date of the approval, and notice of any change in these materials will be published in the
(b) The following materials are available for purchase from the following address: The National Technical Information Services (NTIS), Springfield, Virginia 22166.
(1) Fuel Tank Flammability Assessment Method User's Manual, dated May 2008, document number DOT/FAA/AR-05/8, IBR approved for § 25.981 and Appendix N. It can also be obtained at the following Web site: http://www.fire.tc.faa.gov/systems/fueltank/FTFAM.stm.
(2) [Reserved]