84-21-02 BOEING: Amendment 39-4936. Applies to Boeing Model 747 series airplanes, certificated in all categories, listed in Section 3.0 of Boeing Document No. D6-35022, "Supplemental Structural Inspection Document" (SSID), Revision A, dated April 1984. Compliance is required as indicated in the body of the AD.\n\n\tTo ensure the continuing structural integrity of the total Boeing Model 747 fleet accomplish the following on the candidate fleet, unless already accomplished:\n\n\tA. Within one year after the effective date of the AD, 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 D6-35022, Revision A, dated April 1984, or later FAA approved revisions. 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 proceduresin Sections 5.0 and 6.0 of the SSID.\n\n\tB. Cracked structure must be repaired before further flight in accordance with an FAA approved method. \n\n\tC. Aircraft may be ferried to a maintenance base for repair in accordance with FAR 21.197 and 21.199.\n\n\tD. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.\n\n\tE. Operators who have acceptably incorporated Boeing Document No. D6-35022, Revision A, dated April 1984, or later FAA approved revisions, into their approved maintenance program are exempt from the provisions of this AD.\n\n\tNOTE: Acceptable incorporation is considered to include the reporting requirements of Section 6.0 of the SSID.\n\n\tAll persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. These documents may also be examined at FAA, Northwest Mountain Region, 9010 East Marginal Way South, Seattle, Washington.\n\n\tThe manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1).\n\n\tThis amendment becomes effective November 23, 1984.