AD 97-26-05 Airworthiness Directives; British Aerospace (Jetstream) Model HS 748 Series Airplanes

Models named: HS 748 series. Read the applicability below — it usually turns on serial or part numbers too.

All Model HS 748 series airplanes, certificated in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 (c) of this AD. The request should include an assessment of the effect of the modification, alteration, 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, unless accomplished previously. To prevent fatigue cracking at the inspection hole locations, due to the installation of drive screws, and/or blind rivets, or hole enlargement, which could result in failure of the engine mount structure and consequent separation of the engine from the airplane, accomplish the following: (a) Within 12 months after the effective date of this AD, perform a detailed visual inspection of the inspection holes in all of the aft engine `W' frame socket fittings to determine if drive screws and/or blind rivets have been installed, and to determine if the inspection holes have been reworked, in accordance with PART ONE of the Accomplishment Instructions of British Aerospace (Jetstream) Viscount Preliminary Technical Leaflet (PTL) No. 501, Issue 2, dated June 1, 1994, including Appendix 1, dated January 1, 1994. If a drive screw or blind rivet is installed, or if any inspection hole has been reworked, prior to further flight, accomplish follow-on corrective actions, as applicable, in accordance with PART THREE of the Accomplishment Instructions of the PTL. (b) At the next engine `W' frame removal, or within 24 months after the effective date of this AD, whichever occurs first: Perform a detailed visual inspection of the inspection holes in all of the forward engine `W' frame socket fittings to determine if drive screws and/or blind rivets have been installed, and to determine if the inspection holes have been reworked, in accordance with PART TWO of the Accomplishment Instructions of British Aerospace (Jetstream) Viscount PTL No. 501, Issue 2, dated June 1, 1994, including Appendix 1, dated January 1, 1994. If a drive screw or blind rivet is installed, or if any inspection hole has been reworked, prior to further flight, accomplish follow-on corrective actions, as applicable, in accordance with PART THREE of the Accomplishment Instructions of the PTL. Note 2: Accomplishment of the inspections and/or corrective actions in accordance with Jetstream Service Bulletin HS748-71-33, dated September 2, 1994, is considered acceptable for showing compliance with the requirements of paragraphs (a) and (b) of this AD. (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116. Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116. (d) 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. (e) The actions shall be done in accordance with British Aerospace (Jetstream) Viscount Preliminary Technical Leaflet (PTL) No. 501, Issue 2, dated June 1, 1994, including Appendix 1, dated January 1, 1994. 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 AI(R) American Support, Inc., 13850 Mclearen Road, Herndon, Virginia 20171. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Note 4: The subject of this AD is addressed in British airworthiness directive 002-09-94, dated September 1994. (f) This amendment becomes effective on January 2, 1998. Issued in Renton, Washington, on December 9, 1997. John J. Hickey, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 97-32610 Filed 12-17-97; 8:45 am] BILLING CODE 4910-13-U