COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES GAF N22 and N24 Series Aeroplanes AD/GAF-N22/67 Flap Components - Retirement Lives 5/94 DM Applicability: All Nomad N22 and N24 aircraft. Requirement: Replace the flap control rods (PN 1/N-45-1139/1140) and flap control bellcranks (PN 1/N-45-1017/1018 and -1019/1020) in accordance with ASTA Alert Service Bulletin ANMD-27-44. Compliance: 1.a. For flap control rods which have less than 11800 landings as at 11 March 1994, replace with new control rods before exceeding 12000 landings; and 1.b. For flap control rods which have 11800 or more landings as at 11 March 1994, replace with new control rods within 10 landings from 11 March 1994, or before exceeding 12000 landings, whichever occurs later. Replacement of these flap control rods may be deferred for up to 200 landings by satisfactory completion of an inspection in accordance with paragraph 2.B of ASTA Alert Service Bulletin ANMD-27-44. 2.a. For flap control bellcranks which have less than 9800 landings as at 11 March 1994, replace with new bellcranks before exceeding 10000 landings; and 2.b. For flap control bellcranks which have 9800 or more landings as at 11 March 1994, replace with new bellcranks before exceeding 10000 landings, or within 10 landings from 11 March 1994, whichever occurs later. Replacement of these flap control bellcranks may be deferred for up to 200 landings by satisfactory completion of an inspection in accordance with paragraph 2.B of ASTA Alert Service Bulletin ANMD-27-44. Background: Although the number of landings is the important factor for determining the accumulation of fatigue damage on the flap control components, for convenience, the aircraft manufacturer originally stated their retirement lives in terms of hours (based upon an assumption of one landing per hour of flight). Since some aircraft are consistently flying short flights, with more than one landing per hour of flight, the retirement lives have been re-stated in terms of landings. As a result of this change, some aircraft may now be fitted with components which have exceeded their retirement lives. This AD is issued to ensure that these components are replaced and to make all operators aware of the revised basis for the retirement lives.