79-19-07 R1 COSTRUZIONI AERONAUTICHE GIOVANNI AGUSTA: Amendment 39-3559 as amended by Amendment 39-4430. Applies to Model A109A helicopters equipped with 90 degree gearbox attach sleeve, P/N 109-0435-29-3, certificated in all categories.
Compliance is required as indicated, unless already accomplished.
To prevent possible tail rotor gearbox mounting failure, within the next 50 hours' time in service after the effective date of this AD, and thereafter at intervals not to exceed 100 hours' time in service since the previous inspection, accomplish the following in accordance with Agusta Bollettino Tecnico No. 109-10, Revision A, dated December 17, 1980 (hereinafter referred to as the service bulletin), or an FAA-approved equivalent.
(a) Inspect the tail rotor gear box attach nutplates for condition and security. Replace any defective nutplates that are found.
(b) Inspect the tail rotor gear box attach sleeve and shim, P/N 109-0435-29-3 and P/N 109-0372-18- 5, respectively, for cracks, fretting, nicks, and wear.
(c) If a cracked sleeve or shim is found during the inspection required by paragraph (b) of this AD, replace the defective part with a serviceable part of the same part number or, in the case of sleeves, by P/N 109- 0435-29-5 or P/N 109-0435-31-1.
(d) If a sleeve is found to have wear, fretting, or nicks, during the inspection required by paragraph (b) of this AD, and if:
(1) They are not more than 0.2 mm (0.008 in.) in depth, remove the defect; and
(2) If they are more than 0.2 millimeters (0.008 inch) in depth, replace the sleeve with sleeve of the same part number, or P/N 109-0435-29-5 or P/N 109-0435-31-1.
(e) If a shim is found to have wear, fretting, or nicks during the inspection required by paragraph (b) of this AD, replace the shim with a new part of the same number.
(f) Inspect and, as necessary, correct the alignment and coaxiality between the sleeve and helicopter tail boom, and the sleeve-to-shim flatness fit, in accordance with paragraph 6 of the Service Bulletin or an FAA- approved equivalent.
(g) For purposes of this AD, an FAA-approved equivalent must be approved by the Chief, Aircraft Certification Division, Southwest Region, Federal Aviation Administration, P.O. Box 1689, Fort Worth, Texas 76101, or by the Chief, Aircraft Certification Staff, Federal Aviation Administration, Europe, Africa, and Middle East Office, c/o American Embassy, Brussels, Belgium.
Amendment 39-3559 became effective October 10, 1979.
This Amendment 39-4430 becomes effective August 16, 1982.