81-01-51 SOCIETE NATIONALE INDUSTRIELLE AEROSPATIALE: Amendment 39- 4052. Applies to Models SA360C, SA365C, SA365C1 and SA365C2 helicopters, certificated in all categories, which do not have Aerospatiale modification AMS 365A.07.2457 incorporated.
Compliance required as indicated.
To prevent failures of the tail boom or fin due to fatigue cracking at Frame 9420 accomplish the following unless already accomplished:
(a) For helicopters which have 20 hours' or more total time in service on the effective date of this AD, inspect in accordance with paragraph (c) within 5 hours' time in service.
(b) For those helicopters which have less than 20 hours' total time in service on the effective date of this AD, inspect in accordance with paragraph (c) before reaching 25 hours' time in service.
(c) Inspect for cracks in the outer fairing connecting the fin base leading edge to the tail boom within the transmission shaft passage area at Frame 9420 using the visual method in accordance with Aerospatiale SA360/365 Service Bulletin Number 05.04 dated November 20, 1980, or an FAA-approved equivalent and comply with paragraphs (d), (e), or (f) of this AD as appropriate.
(d) If no cracks are found as a result of the inspection required in paragraph (c) of this AD, return the helicopter to service and repeat the inspection required in paragraph (c) at intervals not to exceed 25 hours' time in service since the last inspection.
(e) If a crack is found as a result of the inspections required in paragraph (c) of this AD that is less than 2 inches (50 mm) long, the helicopter may be returned to service and the inspection required in paragraph (c) of this AD must be done after the last flight of each day.
(f) If a crack is found as a result of the inspections required in paragraph (c) of this AD that is 2 inches (50 mm) or more in length, incorporate Aerospatiale modification AMS 365A.07.2457 or an equivalent noted in paragraph (g) before furtherflight.
(g) The inspections required in paragraph (c) may be discontinued when Aerospatiale modification AMS 365A.07.2457 is incorporated. Equivalent modifications may be approved by the Chief, Aircraft Certification Staff, AEU-100, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, Brussels, Belgium.
NOTE: Aerospatiale SA360/SA365 Service Bulletin Number 53.09 dated November 2, 1980, refers to this modification.
This amendment becomes effective February 28, 1981, to all persons except those persons to whom it was made immediately effective by telegraphic AD T81-01-51, issued December 31, 1980, which contained this amendment.