AD 91-13-11

91-13-11 BOEING: Amendment 39-7042. Docket No. 90-NM-274-AD. Supersedes AD 89- 21-07.

Applicability: Model 747 series airplanes, listed in Boeing Service Bulletin 747-35- 2059, Revision 2, dated March 22, 1990, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent chafing of wire bundles, subsequent arcing and burn-through of adjacent oxygen lines, and a resulting potential fire hazard, accomplish the following:

A. For airplanes listed in Boeing Service Bulletin 747-35-2059, dated August 17, 1989: Within 60 days after October 16, 1989 (the effective date of Amendment 39-6343, AD 89- 21-07), install protective sleeves on wire breakouts and oxygen lines in the upper deck left sidewall in accordance with Boeing Service Bulletin 747-35-2059, dated August 11, 1989; Revision 1, dated November 22, 1989; or Revision 2, dated March 22, 1990.

B. For airplanes listed in Boeing Service Bulletin 747-35-2059, Revision 2, dated March 22, 1990, that are not subject to paragraph A. of this AD: Within 60 days after the effective date of this amendment, install protective sleeves on wire breakouts and oxygen lines in the upper deck left sidewall in accordance with Boeing Service Bulletin 747-35-2059, Revision 2, dated March 22, 1990.

C. An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Seattle ACO.

D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

All persons affected by this directive who have not already received the appropriateservice documents from the manufacturer may obtain copies upon request to Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington.

This amendment supersedes Amendment 39-6343, AD 89-21-07.

This amendment (39-7042, AD 91-13-11) becomes effective on July 22, 1991.