Provides revised guidelines on the marking of aircraft powerplant instruments and electronic displays (cathode ray tubes, etc.).

Sets forth an acceptable means, but not the only means, of demonstrating compliance with the provisions of Title 14, Code of Federal Regulations (14 CFR) part 25 pertaining to the certification requirements for windshields, windows, and mounting structure. Guidance information is provided for showing compliance with § 25.775(d), relating to structural design of windshields and windows for airplanes with pressurized cabins.

This advisory circular (AC) provides guidance material for use as an acceptable means, but not the only means, of demonstrating compliance with the airworthiness standards for transport category airplanes that contain hydraulic system requirements. It is not mandatory and does not constitute a regulation.

Provides guidance material for the airworthiness and operational approval of Traffic Alert and Collision Avoidance Systems (TCAS II) and Mode S transponders.

Sets forth acceptable methods of compliance with provisions of Part 25 of the FAR dealing with the certification requirements for taxi, takeoff, and landing roll design loads. Guidance information is provided for showing compliance with section 25.491 of the FAR relating to structural design for airplane operation on paved runways and taxiways normally used in commercial operations.

This advisory circular describes an acceptable means of showing compliance with the airplane performance and handling characteristics certification requirements for flight in the icing conditions defined in Appendices C and 0 of Title 14, Code of Federal Regulations part 25.

Describes an acceptable means for showing compliance with the requirements of Section 25.905, “Propellers,” of Title 14, Code of Federal Regulations (CFR) Part 25.

The AC provides background and discussion of the reasoning behind the test procedures.

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 material is not mandatory and does not constitute a regulation.

While part 25 contains the airworthiness standards applicable to transport category airplanes, the guidance in this AC pertains to the functions of autopilots, flight directors, and automatic thrust control as well as any interactions with stability augmentation and trim functions.

They are meant to supplement the engineering judgment that must form the basis of any compliance findings for the supercooled large drop icing conditions in §§ 25.773, 25.1323, 25.1324, and 25.1325, as well as the compliance findings for §§ 25.1419 and 25.1420.

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.

Sets forth an acceptable means , but not the only means, of demonstrating compliance with the provisions of part 25 of the Federal Aviation Regulations (FAR) related to the minimum speed margin between design cruise speed and design dive speed for transport category airplanes.

This advisory circular (AC) sets forth an acceptable means, but not the only means, of demonstrating compliance with the provisions of part 25 of the Federal Aviation Regulations (FAR) related to the use of landing gear shock absorption tests and analyses to determine landing loads for transport category airplanes.

It will be incorporated into AC 25-21, “Certification of Transport Airplane Structure” and 25-22, “Certification of Transport Airplane Mechanical Systems” at a later date.