AD 92-06-03

92-06-03 BOEING: Amendment 39-8183. Docket 91-NM-49-AD.

Applicability: Model 747 series airplanes, line number 696 and subsequent; equipped with evacuation system packboards and cover assemblies identified in the Boeing Service Bulletin 747-25-2807, Revision 2, dated August 22, 1991, and Boeing Alert Service Bulletin 747- 25A2889, dated November 1, 1990; certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To provide satisfactory reliability of the evacuation system, accomplish the following:

(a) For evacuation system packboard and cover assemblies identified in either Boeing Service Bulletin 747-25-2807, Revision 2, dated August 22, 1991, or Boeing Alert Service Bulletin 747-25A2889, dated November 1, 1990: Within the next 120 days after the effective date of this AD, inspect the evacuation system packboard and cover assemblies in accordance with Part III, "Accomplishment Instructions," Paragraph B., of Boeing Alert Service Bulletin 747-25A2889, dated November 1, 1990.

(1) If the inspection reveals that the angle measured is 155 degrees or greater, prior to further flight, modify the packboard and cover assemblies in accordance with Boeing Alert Service Bulletin 747-25A2889, dated November 1, 1990, and Boeing Service Bulletin 747-25-2807, Revision 2, dated August 22, 1991, as applicable.

(2) If the inspection reveals that the angle measured is less than 155 degrees, within the next 15 months after the effective date of this AD, modify the packboard and cover assemblies in accordance with Boeing Alert Service Bulletin 747-25A2889, dated November 1, 1990, and Boeing Service Bulletin 747-25-2807, Revision 2, dated August 22, 1991, as applicable.

(b) 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.

(c) 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.

(d) The inspection and modification shall be done in accordance with Boeing Alert Service Bulletin 747-25A2889, dated November 1, 1990; and Boeing Service Bulletin 747-25- 2807, Revision 2, dated August 22, 1991, which contains the following list of effective pages:

Page Number Revision Level Date 1, 3-4 2 August 22, 1991 2, 5, 7, 8, 17-18 1 July 25, 1991 6, 9-16 (original) December 7, 1989

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. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 1100 L Street NW., Room 8401, Washington, DC.

This amendment becomes effective on April 21, 1992.