65-18-03 VICKERS: Amdt. 39-114 Part 39 Federal Register August 14, 1965 as amended by Amendment 39-2282. Applies to Viscount Models 744, 745D and 810 Series Airplanes.
Compliance required as indicated.
Cases of severe corrosion on the bore surfaces of the support tubes of the engine mount assemblies, Drawing Nos. 70037 Sht. 3, 80237 Sht. 3, 80237 Sht. 35 and 81037 Sht. 29 have been reported.
To correct this condition accomplish the following:
(a) Within the next 4,000 hours' time in service or at next engine overhaul period, whichever is the sooner, after the effective date of this AD, unless already accomplished, conduct an inspection of the support tubes in accordance with British Aircraft Corporation Preliminary Technical Leaflet No. 252, Issue 2, dated May 22, 1971, for the 700 Series (for 744 and 745D aircraft), and No. 117, Issue 2, dated May 22, 1971, for the 800/810 Series (for 810 Series aircraft), to determine if corrosion exists on the surface of the bore and, if corrosion exits, to determine its depth.
(1) Accomplish the inspection by radiographic or ultrasonic methods as set forth in the appendices of the applicable Preliminary Technical Leaflet or by FAA-approved equivalent method.
(2) If, on inspection, no corrosion exists or the depth of existing corrosion does not exceed 0.030 inch, subject the support tubes to the dewatering and reprotection scheme set forth in paragraphs 5.1 and 5.1.2 of the applicable Preliminary Technical Leaflet.
(3) Where the depth of corrosion is in excess of 0.030 inch in any section of a support tube, the tube in question must be replaced before further flight.
(b) In addition to the inspection and reprotection requirements in paragraph (a), accomplish the dewatering and reprotection scheme in paragraphs 5.1 and 5.1.2 of the applicable Preliminary Technical Leaflet whenever the engine mount assembly is broken down for any reason. Accomplish the dewatering and reprotection after the end fittings have been assembled.
(c) Within seven years from the date of compliance with paragraph (a) or before the accumulation of 500 hours' time in service after the effective date of this amendment, whichever occurs later, repeat the inspection and action specified in paragraph (a). Thereafter, continue to accomplish the inspection and action specified in paragraph (a) at intervals not to exceed seven years from the last inspection.
Amendment 39-114 became effective September 13, 1965.
This amendment becomes effective August 27, 1975.