84-04-02 AIRBUS INDUSTRIE: Amendment 39-4816. Applies to Model A300 B2 and B4 series airplanes, that have not incorporated modification No. 1642, described in Airbus Industrie Service Bulletin A300-55-017, Revision 3, dated November 5, 1979. Compliance is required as indicated, unless already accomplished. To detect cracks in the upper machined skins of the lefthand, righthand, and center spar boxes of the horizontal stabilizer, and to prevent the possible structural failure of the horizontal stabilizer, accomplish the following:
A. Prior to the accumulation of 12,000 hours time in service, or within the next 300 hours time in service after the effective date of this AD, whichever occurs later, unless already accomplished, inspect the upper skins of the horizontal stabilizer's lefthand, righthand, and center spar boxes in accordance with the instructions in paragraph 2.B inspection, of Airbus Industrie Service Bulletin A300-55-022, Revision 1, dated March 28, 1979.
B.Repeat the inspection required in paragraph A. of this AD at intervals not exceeding 3,000 hours total time in service from the last inspection until the aircraft has accumulated 21,000 hours total time in service. After 21,000 hours total time in service have been accumulated, perform the inspection required in paragraph A. of this AD at intervals not exceeding 1,500 hours time in service from the last inspection.
C. If cracks are found during the inspections required by paragraphs A. or B. of this AD, perform inspections and repairs in accordance with the Modification, Inspection and Repair Alternatives Flow Chart in Figure 1 of the Service Bulletin and continue the inspection required by paragraphs A. or B.
D. Incorporation of Airbus Industrie Modification 1642 constitutes terminating action to the requirements of this AD.
E. 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.
F. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD.
This amendment becomes effective March 28, 1984.