AD 99-26-09

99-26-09 BOEING: Amendment 39-11468. Docket 97-NM-186-AD. Issued December 9, 1999.

Applicability: Model 767 series airplanes, powered by Pratt & Whitney Model JT9D or Model PW4000 series engines, as listed in Boeing Alert Service Bulletin 767-71A0087, dated October 10, 1996; 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 (e) 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 requestshould include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent possible separation of the engine from the airplane in the event of a primary thrust linkage failure, accomplish the following:

Initial and Repetitive Inspections

(a) For Groups 1 and 2 airplanes: Accomplish paragraphs (a)(1), (a)(2), and (a)(3) of this AD, as applicable, in accordance with Boeing Alert Service Bulletin 767-71A0087, dated October 10, 1996.

(1) Within 500 flight hours or 300 flight cycles after the effective date of this AD, whichever occurs later: Accomplish Work Package 1 (a detailed visual inspection of the forward engine mount to ensure that the thrust link, evener bar, associated lugs, and attaching hardware are firmly attached). Thereafter, repeat Work Package 1 at the intervals specified in the alert service bulletin until the requirements of either paragraph (a)(2) or (a)(3) of this AD are accomplished.NOTE 2: For the purposes of this AD, a detailed visual inspection is defined as: "An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate by the inspector. Inspection aids such as mirrors, magnifying lenses, etc. may be used. Surface cleaning and elaborate access procedures may be required."

(2) Prior to the accumulation of 16,000 total flight cycles on any engine or within 500 flight hours or 300 flight cycles after the effective date of this AD, whichever occurs later: Accomplish Work Package 2 (non-destructive test inspection of the forward engine mount to ensure the proper condition of the engine thrust link components). Thereafter, repeat Work Package 2 on that engine at the intervals specified in the alert service bulletin until the requirements of paragraph (a)(3)of this AD are accomplished. Accomplishment of Work Package 2 constitutes terminating action for the repetitive inspections required by paragraph (a)(1) of this AD for that engine.

Replacement and Terminating Action

(3) Within 3 years after the effective date of this AD: Accomplish Work Package 3 (end cap and bolt replacement of the forward engine mount). Accomplishment of Work Package 3 constitutes terminating action for the requirements of this AD for Groups 1 and 2 airplanes.

(b) For Group 3 airplanes: Within 3 years after the effective date of this AD, accomplish Work Package 4 (bolt replacement) in accordance with Boeing Alert Service Bulletin 767-71A0087, dated October 10, 1996.

Repair and Replacement Action

(c) For all airplanes: If any discrepancy (including an improperly installed or damaged engine thrust link component) is found during any inspection required by this AD, prior to further flight, accomplish the actions required by paragraphs (c)(1)and (c)(2) of this AD. (1) Repair any discrepancies in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. For a repair method to be approved by the Manager, Seattle ACO, as required by this paragraph, the Manager's approval letter must specifically reference this AD. (2) Accomplish Work Package 3 in accordance with Boeing Alert Service Bulletin 767-71A0087, dated October 10, 1996.

Spares

(d) As of the effective date of this AD, no person shall install a forward engine mount end cap having part number 310T3026-1 on any airplane.

Alternative Method of Compliance

(e) 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 ACO. 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 3: 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

(f) 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.

Incorporation by Reference

(g) Except as provided by paragraph (c)(1) of this AD, the actions shall be done in accordance with Boeing Alert Service Bulletin 767-71A0087, dated October 10, 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.

(h) This amendment becomes effective on January 24, 2000.