AD 97-11-12 Airworthiness Directives; Aerospace Technologies of Australia Pty Ltd. (Formerly Government Aircraft Factory) Models N22B, N22S, and N24A Airplanes

Models named: N22B, N22S, N24A. Read the applicability below — it usually turns on serial or part numbers too.

Models N22B, N22S, and N24A airplanes (all serial numbers), certified in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alternation, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated in the body of this AD, unless already accomplished. To prevent structural failure of the front spar caused by cracks in the stub wing upper front spar cap flanges, which would result in loss of control of the airplane, accomplish the following: (a) Prior to accumulating 1,700 hours time-in-service (TIS) or within the next 300 hours TIS after the effective date of this AD, whichever occurs later, and thereafter at intervals not to exceed 2,650 hours TIS, inspect, using both visual and eddy current methods, the stub wing front spar cap flanges in the area of Buttock Line (BL) 47.6 for fatigue cracks in accordance with the ACCOMPLISHMENT INSTRUCTIONS section of Nomad Service Bulletin NMD- 53-6, dated October 21, 1986. (b) If any crack is found during any inspection required by this AD, prior to further flight, obtain a repair scheme from the manufacturer through the Los Angeles Aircraft Certification Office (ACO) at the address specified in paragraph (d) of this AD, and incorporate this repair scheme. This repair does not eliminate the repetitive inspection requirement of this AD. (c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. (d) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, FAA, Los Angeles ACO, 3960 Paramount Boulevard, Lakewood, [[Page 28999]] California 90172. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. (e) The inspections required by this AD shall be done in accordance with Nomad Service Bulletin NMD-53-6, dated October 21, 1986. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Aerospace Technologies of Australia Pty Ltd., ASTA DEFENCE, Private Bag No. 4, Beach Road Lara 3212, Victoria, Australia. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (f) This amendment (39-10041) becomes effective on July 11, 1997. Issued in Kansas City, Missouri, on May 22, 1997. Henry A. Armstrong, Acting Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 97-14077 Filed 5-28-97; 8:45 am] BILLING CODE 4910-13-U