95-24-14: Pivot Tube in Drag Strut of NLG

95-24-14 DE HAVILLAND, INC.: Amendment 39-9444. Docket 95-NM-219-AD. Applicability: Model DHC-8 series airplanes, serial numbers 003 through 403 inclusive; and Model DHC-8 series airplanes on which a drag strut having serial numbers DEC 001/83 through DCL 432/94 inclusive is installed; as listed in Bombardier Service Bulletin S.B. 8-32- 131, dated September 8, 1995; certificated 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 use the authority provided in paragraph (d) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD. Compliance: Required as indicated, unless accomplished previously. To prevent failure of the pivot tube in the drag strut of the nose landing gear (NLG) and a subsequent nose gear-up landing, accomplish the following: (a) Prior to the accumulation of 13,400 total landings on the drag strut assembly, or within 30 days after the effective date of this AD, whichever occurs later: Perform an eddy current inspection to detect cracking of the pivot tube, part number (P/N) 8225-3, located in the drag strut of the NLG, in accordance with Bombardier Service Bulletin S.B. 8-32-131, dated September 8, 1995. NOTE 2: The Bombardier service bulletin includes (asan attachment) Messier-Dowty Service Bulletin M-DT DHC8-32-77, dated July 5, 1995. The Messier-Dowty service bulletin details the specific procedures for accomplishment of the requirements of this AD. (1) If no cracking is found, repeat the inspection required by paragraph (a) of this AD thereafter at intervals not to exceed 2,000 landings. (2) If any cracking is found that can be removed completely by reworking the pivot tube in accordance with the service bulletin, prior to further flight, repair the pivot tube in accordance with the service bulletin. Thereafter, repeat the inspection required by paragraph (a) of this AD at intervals not to exceed 1,000 landings. (3) If any cracking is found that cannot be removed completely by reworking the pivot tube in accordance with the service bulletin, prior to further flight, accomplish paragraph (a)(3)(i) or (a)(3)(ii) of this AD in accordance with the service bulletin. (i) Replace the cracked pivot tube with a serviceable tube having P/N 8225-3. Thereafter, perform the repetitive inspections required by paragraph (a) of this AD. Or (ii) Replace the cracked pivot tube with a new strengthened tube having P/N 8225-5. No further action is required by this AD. (b) Replacement of a pivot tube having P/N 8225-3 with a pivot tube having P/N 8225-5 (de Havilland Modification 8/2266), in accordance with Bombardier Service Bulletin S.B. 8-32-131, dated September 8, 1995, constitutes terminating action for the inspection requirements of this AD. (c) As of the effective date of this AD, no person shall install a drag strut assembly having serial numbers DEC 001/83 through DCL 432/94 inclusive on any airplane unless that assembly has been inspected and found to be crack-free, or unless that assembly has been inspected and repaired, in accordance with the requirements of this AD. (d) An alternative method of compliance or adjustment of the compliance time that provides an acceptablelevel of safety may be used if approved by the Manager, New York Aircraft Certification Office (ACO), FAA, Engine and Propeller Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO. NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO. (e) 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. (f) The actions shall be done in accordance with Bombardier Service Bulletin S.B. 8-32-131, dated September 8, 1995. 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 obtainedfrom Bombardier, Inc., Bombardier Regional Aircraft Division, Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, New York Aircraft Certification Office, Engine and Propeller Directorate, 10 Fifth Street, Third Floor, Valley Stream, New York; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (g) This amendment becomes effective on December 18, 1995.