AD 99-10-08 Airworthiness Directives; Boeing Model 767 Series Airplanes

Models named: 767 series. Read the applicability below — it usually turns on serial or part numbers too.

Model 767 series airplanes, manufacturer's line positions 001 through 455 inclusive, 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 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 corrosion of the forward trunnion joint of the main landing gear (MLG), which could lead to a stress corrosion fracture of the forward trunnion and possible consequent collapse of the MLG, accomplish the following: (a) Within 6 years since the outer cylinder of the MLG was new, last overhauled, or installed (replaced) after the last corrosion repair in accordance with Boeing Alert Service Bulletin 767-32A0127, dated January 29, 1996; or within 18 months after the effective date of this AD; whichever occurs later: Perform a detailed visual inspection to detect corrosion inside the forward trunnion joint and the internal threads of the MLG; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767- 32A0127, dated January 29, 1996. (1) If no corrosion of the forward trunnion joint is found, prior to further flight, accomplish either paragraph (a)(1)(i) or (a)(1)(ii) of this AD. (i) Apply chrome plating to the forward trunnion thrust and tab faces and apply corrosion-inhibiting compound to the trunnion joint in accordance with the alert service bulletin. Accomplishment of this application of chrome plating constitutes terminating action for the requirements of this AD. (ii) Apply corrosion-inhibiting compound to the forward trunnion joint in accordance with the Accomplishment Instructions of the alert service bulletin. Repeat the detailed visual inspection thereafter at intervals not to exceed six years or until chrome plating is applied to the forward trunnion thrust and tab faces and corrosion-inhibiting compound is applied to the trunnion joint, in accordance with the alert service bulletin. (2) If any corrosion of the forward trunnion joint is found, prior to further flight, accomplish either paragraph (a)(2)(i) or (a)(2)(ii) of this AD. (i) Repair the forward trunnion, apply chrome plating to the forward trunnion thrust and tab faces, and apply corrosion- inhibiting compound; in accordance with the alert service bulletin. Accomplishment of this application of chrome plating and corrosion- inhibiting compound constitutes terminating action for the requirements of this AD. (ii) Repair the forward trunnion and apply corrosion-inhibiting compound to the forward trunnion joint in accordance with the alert service bulletin. Repeat the detailed visual inspection thereafter at intervals not to exceed six years or until chrome plating is applied to the forward trunnion thrust and tab faces in accordance with the alert service bulletin. (b) Replacement, repair, or overhaul of the outer cylinder of the MLG that includes the application of chrome plating to the forward trunnion thrust and tab faces and application of corrosion- inhibiting compound, in accordance with Boeing Alert Service Bulletin 767-32A0127, dated January 29, 1996, constitutes terminating action for the requirements of this AD. Alternative Methods of Compliance (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, Seattle Aircraft Certification Office (ACO), 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, Seattle ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. Special Flight Permits (d) Special flight permits may be issued in accordance with Secs. 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. Incorporation by Reference (e) The actions shall be done in accordance with Boeing Alert Service Bulletin 767-32A0127, dated January 29, 1996. 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 Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. 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. (f) This amendment becomes effective on June 11, 1999. Issued in Renton, Washington, on April 30, 1999. D. L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-11468 Filed 5-6-99; 8:45 am] BILLING CODE 4910-13-U