AD 94-01-15

94-01-15 BOEING: Amendment 39-8797. Docket 93-NM-138-AD.

Applicability: Model 747 series airplanes with a stretched upper deck, all line numbers up to and including line number 980; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent the bulb seal from coming off the fascia panels and being ingested into the turbofans of the escape systems on the stretched upper deck (SUD), which could impede the inflation of the escape slide during an emergency situation, accomplish the following:

(a) Within 6 months after the effective date of this AD, install an aluminum seal retainer on the bulb seal attached to the fascia panel of the escape systems on the SUD, in accordance with Boeing Alert Service Bulletin 747-25A3056, dated July 12, 1993.

(b) 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). 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: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

(c) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished.

(d) The installation shall be done in accordance with Boeing Alert Service Bulletin 747-25A3056, dated July 12, 1993. 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; at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(e) This amendment becomes effective on March 3, 1994.