83-23-06 BRITISH AEROSPACE AIRCRAFT GROUP: Amendment 39-4767. Applies to Model HS 748 series 2A and 2B airplanes certificated in all categories. To prevent structural failure of the engine subframe, accomplish the following, unless already accomplished:
A. Prior to 7 years from date of manufacture, or within the next 12 months after the effective date of this AD, whichever occurs later, inspect engine subframe struts and perform the appropriate actions in accordance with paragraph 2, Accomplishment Instructions, of British Aerospace Aircraft Group HS 748 Service Bulletin 54/25, Revision 4, dated May 1979.
B. Repeat the inspections of the subframe struts at seven year intervals from the last inspection.
C. 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.
D. 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 December 15, 1983.