AIRCRAFT MAINTENANCE - SPECIAL FLIGHT PERMITS

AIRWORTHINESS DIRECTIVES
A primary safety function of the FAA is to require correction of unsafe conditions found in an aircraft, aircraft engine, propeller, or appliance when such conditions exist and are likely to exist or develop in other products of the same design. The unsafe condition may exist because of a design defect, maintenance, or other causes. 14 CFR part 39, Airworthiness Directives (ADs), defines the authority and responsibility of the Administrator for requiring the necessary corrective action. ADs are the means used to notify aircraft owners and other interested persons of unsafe conditions and to specify the conditions under which the product may continue to be operated.
ADs may be divided into two categories:

1. those of an emergency nature requiring immediate compliance prior to further flight, and
2. those of a less urgent nature requiring compliance within a specified period of time.

Airworthiness Directives are regulatory and shall be complied with unless a specific exemption is granted.

It is the aircraft owner or operator's responsibility to ensure compliance with all pertinent ADs. This includes those ADs that require recurrent or continuing action. For example, an AD may require a repetitive inspection each 50 hours of operation, meaning the particular inspection shall be accomplished and recorded every 50 hours of time in service.

Owners/operators are reminded there is no provision to overfly the maximum hour requirement of an AD unless it is specifically written into the AD. To help determine if an AD applies to an amateur-built aircraft, contact the local FSDO.

14 CFR part 91, section 91.417 requires a record to be maintained that shows the current status of applicable ADs, including the method of compliance; the AD number and revision date, if recurring; the time and date when due again; the signature; kind of certificate; and certificate number of the repair station or mechanic who performed the work. For ready reference, many aircraft owners have a chronological listing of the pertinent ADs in the back of their aircraft, engine, and propeller maintenance records.

All Airworthiness Directives and the AD Biweekly are free on the Internet at www.airweb.faa.gov/rgl Paper copies of the Summary of Airworthiness Directives and the AD Biweekly may be purchased from the Superintendent of Documents. The Summary contains all the valid ADs previously published and is divided into two areas. The small aircraft and rotorcraft books contain all ADs applicable to small aircraft (12,500 pounds or less maximum certificate takeoff weight) and ADs applicable to all helicopters. The large aircraft books contain all ADs applicable to large aircraft.

For further information on how to order ADs and the current price, contact:
U.S. Department of Transportation Federal Aviation Administration Delegation & Airworthiness Programs Branch, AIR-140
P.O. Box 26460
Oklahoma City, OK 73125
Telephone Number: (405) 954-4103
Fax: (405) 954-4104