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United States Department of Transportation United States Department of Transportation

Advisory Circulars (ACs)

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Number, title, description, or office

Advisory Circulars (ACs) search results
Number Title Status Office Date
91-50 Importance of Transponder Operation and Altitude Reporting

Provides information and guidance concerning the importance of transponder operation and altitude reporting in the National Airspace System.

Active AFS-820 1977-08-24
91-53A Noise Abatement Departure Profile

Describes acceptable criteria for safe noise abatement departure profiles (NADP) for subsonic turbojet-powered airplanes with a maximum certificated gross takeoff weight of more than 75,000 pounds.

Active AFS-820 1993-07-22
91-32B Safety in and Around Helicopters

This Advisory Circular (AC) provides safety guidelines for persons associated with helicopter operations and suggests ways to avoid hazards and reduce the risk of accidents.

Active AFS-820 1997-02-18
91-58A Use of Pyrotechnic Visual Distress Signaling Devices in Aviation

This advisory circular (AC) suggests standards and procedures for the acquisition, use, and storage of pyrotechnic visual distress signaling devices that are intended for use in aircraft emergencies.

Active AFS-820 2000-02-10
91-65 Use of Shoulder Harness in Passenger Seats

Provides guidance and information to pilots, passengers, and maintenance personnel regarding the crash survivability aspects of small aircraft equipped with shoulder harnesses and the hazards of modifying seats, adding appendages to seats, and storage of articles, beneath the seats.

Active AFS-820 1986-08-04
91-71 Operation of Hot Air Balloons with Airborne Heaters

Provides guidance for the safe and practical operation of hot air balloons with airborne heaters in compliance with appropriate portions of 14 CFR 91.

Active AFS-820 1996-06-13
91-48 Acrobatics-Precision Flying with a Purpose

Provides information to persons who are interested in acrobatic flying to improve their piloting skills as recreation, sport, or as a competitive activity.

Active AFS-820 1977-06-29
91-68 Pilot Qualification and Operation of all Surplus Military Turbine-Powered Airplanes

Provides information and guidance to pilots who wish to become qualified to operate surplus military turbine-powered airplanes under a letter of authorization, as required by operating limitations issued for this type of aircraft.

Active AFS-820 1992-02-25