AD 93-06-01

93-06-01 BOEING: Amendment 39-8526. Docket 92-NM-148-AD. Supersedes AD 84-21-02 R1, Amendment 39-6430.

Applicability: Model 747 series airplanes, as listed in Section 3.0 of Boeing Document No. D6-35022, "Supplemental Structural Inspection Document" (SSID), Revision D, dated February 1992, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To ensure the continuing structural integrity of the total Boeing Model 747 fleet, accomplish the following:

(a) For airplanes listed in Boeing Document No. D6-35022, Revision C, dated April 1989: Within 3 months after February 12, 1990 (the effective date of AD 84-21-02 R1, Amendment 39-6430), incorporate a revision into the FAA-approved maintenance inspection program which provides no less than the required Damage Tolerance Rating (DTR) for each Structural Significant Item (SSI) listed in Boeing Document No. D6-35022, Revision C, dated April 1989. (The required DTR value for eachSSI is listed in the document.) The revision to the maintenance program shall include and be implemented in accordance with the procedures in Sections 5.0 and 6.0 of the SSID.

(b) For airplanes listed in Boeing Document No. D6-35022, Revision D, dated February 1992: Within 12 months after the effective date of this AD, replace the revision of the FAA-approved maintenance inspection program required by paragraph (a) of this AD with a revision that provides no less than the required DTR for each SSI listed in Boeing Document No. D6-35022, Revision D, dated February 1992. (The required DTR value for each SSI is listed in the document.) The revision to the maintenance program shall include and be implemented in accordance with the procedures in Sections 5.0 and 6.0 of the SSID.

(c) Cracked structure must be repaired, prior to further flight, in accordance with an FAA-approved method.

(d) An alternative method of compliance or adjustment of the compliance time that providesan acceptable level of safety may be used if approved by the Manager, Seattle 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, 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.

(e) 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.

(f) The inspections shall be done in accordance with Boeing Document No. D6-35022, "Supplemental Structural Inspection Document (SSID)", Revision C, dated April 1989, and Boeing Document No. D6-35022, "Supplemental Structural Inspection Document (SSID)", Revision D, dated February 1992, comprised of Volumes I and II, which includes the following list of effective pages:

Page Number Revision Ltr.

List of Active Pages D Pages 1 thru 21.1

(NOTE: The issue date of Revision D is indicated only on the title page; no other page of the document is dated.) The incorporation by reference of Revision D was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. The incorporation by reference of Revision C was approved previously by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51 as of February 12, 1990 (55 FR 1005, January 11, 1990). 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.

(g) This amendment becomes effective on May 17, 1993.