65-19-05 VICKERS: Amdt. 39-127 Part 39 Federal Register August 26, 1965. Applies to Viscount Models 744 and 745D Series Airplanes Equipped with Main Landing Gear Top Yokes of DTD 683 Aluminum Alloy.
Compliance required as indicated.
To prevent further failures of the main landing gear top yokes, accomplish the following:
(a) Within the next 25 landings after the effective date of this AD, visually inspect the top yoke for cracks in accordance with British Aircraft Corporation (BAC) Ltd. Preliminary Technical Leaflet (PTL) No. 255 (700 Series) or later ARB-approved issue and thereafter at intervals not to exceed 25 landings from the last inspection until modified in accordance with (d) of this AD.
(b) If cracks are found, within the next five landings
(1) Repair the yoke in accordance with Modification D.3154, part (b) or (d) as applicable or an equivalent approved by the Chief, Aircraft Certification Staff, European Region, and reinspect at intervals not to exceed 100 landings in accordance with PTL No. 255 or later ARB-approved issue until modified in accordance with (d) of this AD; or
(2) Replace the yoke.
(c) Replace within the next five landings any yoke found with a propagating crack during the inspection required by (b)(1).
(d) The repetitive inspections required by (a) and (b)(1) may be discontinued after installation of BAC Modification D.3154 part (a) or (c), as applicable, a replacement yoke of L.65 material in accordance with BAC Modification D.1468, or an equivalent approved by the Chief, Aircraft Certification Staff, European Region.
(e) For the purpose of complying with this AD, subject to acceptance by the assigned FAA maintenance inspector, the number of landings may be determined by dividing each airplane's hours' time in service by the operator's fleet average time from takeoff to landing for the airplane type.
This directive effective September 5, 1965.