AD 93-12-03

93-12-03 MCDONNELL DOUGLAS: Amendment 39-8609. Docket 93-NM-81-AD.

Applicability: Model MD-11 series airplanes, as listed in McDonnell Douglas MD-11 Alert Service Bulletin A28-56, Revision 1, dated June 14, 1993, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent fuel leakage into the center cargo bilge area that could lead to a fire in the cargo compartment, accomplish the following:

(a) Within 30 days after the effective date of this AD, modify the plumbing on the forward spar of the tail fuel tank in accordance with the Accomplishment Instructions of McDonnell Douglas MD-11 Alert Service Bulletin A28-56, dated May 25, 1993, or Revision 1, dated June 14, 1993.

(b) Immediately following the modification, prior to further flight, perform a pressure check of the fuel shroud drain system in accordance with the Accomplishment Instructions of McDonnell Douglas MD-11 Alert Service Bulletin A28-56, dated May 25, 1993, or Revision 1, dated June 14, 1993.

(1) If the fuel shroud drain system fails the pressure check, prior to further flight, accomplish the requirements in paragraph (b)(1)(i) and (b)(1)(ii) of this AD.

(i) Repair, or replace the failed line with a serviceable or new line and repeat the pressure check of the fuel shroud drain system in accordance with the Accomplishment Instructions of either service bulletin.

(ii) Inspect the insulation blankets in the center cargo bilge area to detect fuel contamination and replace any fuel contaminated insulation blanket with a serviceable blanket in accordance with the Accomplishment Instructions of McDonnell Douglas MD-11 Alert Service Bulletin A28-56, Revision 1, dated June 14, 1993.

(2) If the fuel shroud drain system passes the pressure check, no further action is required by this AD.

(c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safetymay be used if approved by the Manager, Los Angeles 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, Los Angeles ACO.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO.

(d) 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.

(e) The modification, pressure check, and repair or replacement shall be done in accordance with McDonnell Douglas MD-11 Alert Service Bulletin A28-56, dated May 25, 1993; or McDonnell Douglas MD-11 Alert Service Bulletin A28-56, Revision 1, dated June 14, 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 McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, California 90801-1771, Attention: Business Unit Manager, Technical Publications - Technical Administrative Support, C1-L5B. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(f) This amendment becomes effective on July 7, 1993.