Advisory Circulars

Describes acceptable means for showing compliance with certain requirements of Title 14, CFR, of FAR 25.1329, Flight Guidance System. While Part 25 contains the airworthiness standards applicable to transport category airplanes, the guidance in this AC pertains to the functions of autopilots, as well as any interactions with stability augmentation and trim functions.

This advisory circular (AC) provides guidance for the airworthiness approval of airborne windshear warning systems in transport category airplanes. Like all advisory circular material, this advisory circular is not, in itself, mandatory and does not constitute a regulation. It is issued for guidance purposes and to outline a method of compliance with the rules. In lieu of following this method without deviation, the applicant may elect to follow an alternate method, provided the alternate method is also found by the Federal Aviation Administration (FAA) to be an acceptable means of complying with the requirements of Part 25 of the Federal Aviation Regulations (FAR). Because the method of compliance presented in this AC is not mandatory, the terms "shall" and "must" used in this AC apply only to an applicant who chooses to follow this particular method without deviation.

Provides guidance material for the airworthiness and operational approval of Traffic Alert and Collision Avoidance Systems (TCAS II) and Mode S transponders. Like all AC material, this AC is not mandatory and does not constitute a regulation. Issued for guidance purpose and to outline a method of compliance with the rules.

Identifies the information that must be provided in Airplane Flight Manual (AFM) under the airworthiness regulations and provides guidance as to the form and content of the approved portion of an AFM.

This Advisory Circular (AC) provides acceptable certification methods, but not necessarily the only acceptable methods, for demonstrating compliance with the crashworthiness requirements of part 25, as amended through Amendment 25-112, of Title 14 of the Code of Federal Regulations (14 CFR) for transport category airplanes. The guidance in this AC is not mandatory nor a regulation.

Sets forth an acceptable means, but not the only means, of demonstrating compliance with the provisions of 14 CFR Part 25 related to the aircraft design for sustained engine rotor imbalance conditions. While these guidelines are not mandatory, they are derived from extensive Federal Aviation Administration (FAA) and industry experience in determining compliance with the pertinent Federal Aviation Regulations (FAR).

Provides guidance on the various aspects that should be considered in the FAA approval process of fire extinguishing system components manufactured under a Production Certificate (PC), components to be FAA approved under the Part Manufacturer Approval (PMA) process, or design changes to components originally approved by either method. This AC does not constitute a regulation, however, it provides a method, for obtaining approval of aircraft fire extinguishing system components. This is intended to enhance the standardization of all FAA Aircraft Certification Offices (ACO) and Manufacturing Inspection District Offices (MIDO) in the approval process of the critical components of an aircraft fire extinguishing system.

This advisory circular (AC) provides guidance for demonstrating compliance with the transport category airplane certification requirements of § 25.1360 Precautions against injury

This Advisory Circular (AC) provides an acceptable means of showing compliance with the requirements of Title 14, Code of Federal Regulations (CFR), part 25, § 25.795(b)(2), “Cabin smoke protection.” This section requires that an airplane be designed with means to prevent passengers from being incapacitated by smoke, fumes, and noxious gases that result from detonation of an explosive or incendiary device during flight. The means of compliance described in this document provides guidance to supplement the engineering and operational judgment that must form the basis of any compliance findings relative to penetration of smoke, fumes, and noxious gases into the passenger cabin.

This advisory circular (AC) describes an acceptable means for showing compliance with certain requirements of Title 14, Code of Federal Regulations (CFR) part 26 and how the results of that compliance relate to certain complementary operational rules. The standards in part 26 may require performing assessments, developing design changes, and revising instructions for continued airworthiness for transport category airplanes. This AC provides generic guidance that is applicable to the safety initiatives in part 26 that may be issued (i.e., Enhanced Airworthiness Program for Airplane Systems, Reduction of Fuel Tank Flammability in Transport Category Airplanes, Aging Airplane Safety, and Widespread Fatigue Damage). This AC provides generic guidance on the roles and responsibilities of type certificate and supplemental type certificate holders, manufacturers, owners, and operators. This AC provides guidance on the processes for developing compliance plans, data, and information that would be available to operators to meet the safety objectives.

This advisory circular (AC) sets forth an acceptable means, but not the only means, for demonstrating compliance to the following by computer modeling analysis techniques validated by dynamic tests: • Title 14 Code of Federal Regulations (14 CFR) parts 23, 25, 27, and 29, §§ 23.562, 25.562, 27.562, and 29.562. • The Technical Standard Order (TSO) associated with the above regulations, TSO-C127/C127a.

Outlines acceptable methods, but not the only methods, for measuring cabin interior emergency illumination on transport airplanes, and provides information as to suitable measuring instruments.

This advisory circular (AC) describes an acceptable means for showing compliance with the requirements of Title 14, Code of Federal Regulations (CFR), part 25, § 25.795(c), “Least risk bomb location.” This section requires that a location on the airplane be designed where an explosive or incendiary device may be placed to protect flight critical structures and systems from damage in case of detonation. The means of compliance described in this document provide guidance to supplement the engineering and operational judgment that must form the basis of any compliance findings relative to the design of a Least Risk Bomb Location on an airplane.

This advisory circular (AC) describes an acceptable means for showing compliance with the requirements of Title 14, Code of Federal Regulations (14 CFR), part 25, § 25.795(c)(3), “Interior design to facilitate searches.” This section requires that the interior design of an airplane incorporate features that will make it more difficult to hide dangerous objects in the airplane or make it easier to find them if they have been brought onboard. The means of compliance described in this document provides guidance to supplement the engineering and operational judgment that must form the basis of any compliance findings relative to whether the interior design deters concealment of dangerous objects (e.g., weapons or explosives) and facilitates a search for them in certain areas of the airplane. The requirements for searching an airplane are not affected by the requirements of § 25.795(c)(3). The design of the airplane will make it easier to search for hidden objects but will not affect the need for, or the diligence of, the search.

Provides instructions to ensure continued airworthiness of structural repairs on transport category airplanes. It addresses the approval procedures to follow when making structural repairs to structure certificated under the damage tolerance requirements of Section 25.571 of FAR, Amendment 25-45, and to type designs with Supplemental Inspection Documents, which were based on these criteria.

This advisory circular (AC) describes an acceptable means of showing compliance with the requirements of Title 14, Code of Federal Regulations (14 CFR), part 25, § 25.795(b)(1), “Flight deck protection.” This section requires that an airplane be designed to limit the entry of smoke, fumes, and noxious gases into the flightdeck in the event of detonation of an explosive or incendiary device on the airplane. The means of compliance described in this document provides guidance to supplement the engineering and operational judgment that must form the basis of any compliance findings relative to penetration into the flightdeck of smoke, fumes, and noxious gases generated by explosions or fires elsewhere on the airplane.

This Advisory Circular (AC) provides guidance for showing compliance with certain requirements of Title 14 of the Code of Federal Regulations (14 CFR), part 25, for the design approval of flightcrew-alerting functions

This advisory circular (AC) sets forth an acceptable means, but not the only means, of demonstrating compliance with the provisions of the airworthiness standards for transport category airplanes related to the airplane design for flightdeck (also referred to as the pilot compartment or cockpit) intrusion resistance. Intrusion resistance, in the context of this AC, refers to the ability to resist forced entry by a person who is not authorized by the pilot in command to enter the flightdeck. Intrusion resistance also includes the ability to resist attempts to enter the flightdeck through use of simple tools, such as pocket knives, nail files, or keys.

This advisory circular (AC) sets forth an acceptable means, but not the only means, of demonstrating compliance with the provisions of the airworthiness standards for transport category airplanes related to the airplane design for flightdeck penetration resistance.

This advisory circular

CAe) provides information and guidance regarding an acceptable means, but not the only means, of compliance with th~ portions of 14 Code of Federal Regulations (CFR) 25.785 and 14 CFR 121.311, which deal with flight attendant seats. This material is for guidance purposes; it is not mandatory and does not constitute a regulation. The guidelines incorporated in this AC are intended to address the adequacy of new designs and are not intended to require that in·service airplanes be modified solely for the purpose of meeting them. Voluntary modifications to existing cabins are not required to meet the new criteria but modifiers should incorporate them to the extent practical considering the scope and intent of the voluntary modification.

Sets forth an acceptable means, but not the only means, of complying with the requirement for a 2-inch colored band outlining exits required to be openable from the outside on transport airplanes.

This advisory circular (AC)offers guidance on compliance with Title 14 Code of Federal Regulations (14 CFR) 26.21, 26.23, 121.1115, and 129.115.  It tells design approval holders of transport category airplanes how to establish a limit of validity of the engineering data that supports the structural maintenance program (hereafter referred to as LOV) for those airplanes. It also tells design approval holders how to address maintenance actions that have been determined necessary to support an LOV.  It tells operators of those airplanes how to incorporate the LOV into their maintenance programs.  Finally, this AC provides guidance to anyone wishing to extend an LOV.  Guidance for establishing an LOV for airplanes whose type certificate was applied for after (XXXX) is contained in AC 25.571-1X.  Guidance for extending an LOV approved under § 25.571, § 26.21, or § 26.23 can be found here.  The actions described in this AC are meant to prevent widespread fatigue damage (WFD) in the transport airplane fleet up to the LOV.