AD 61-03-06

61-03-06 VICKERS: Amdt. 246 Part 507 Federal Register February 2, 1961. Applies to All Viscount Model 745D Aircraft With Dunlop "Inorganic" AH.50961/2 Main Wheel Brake Units.

Compliance required as indicated, unless already accomplished.

Due to failure of the main landing gear ram foot fitting brake attachment flange Pre-mod. .2781 standard, the following must be accomplished.

(a) All brake, units P/N AH.50961/2 in service must be inspected at the next main wheel removal to ensure that shoulders of dowels) P/N AHO.36232) do not protrude above the surface of the torque plate, P/N AH.41181/2. Spare brake units must be inspected prior to installation.* Brake units on which the shoulders of the dowels are found to protrude above the surface of the torque plate are considered unairworthy until reworked in accordance with Vickers PTL No.225 or FAA approved equivalent.

(b) When conducting the above inspection also inspect the ram foot fitting for cracks on the inside surface of the top portion of the brake attachment flange, with special attention to the blend radius at the base of the flange, using dye penetrant or FAA approved equivalent. If cracks are found in an area of the flange between the brake attachment holes and the blend radius itself, the ram foot fitting must be replaced or repaired prior to further flight. The defective part may be repaired in accordance with Vickers Mod. D.3000 or FAA approved equivalent provided only one flange is cracked. The ram foot fitting must be replaced if both flanges are cracked.

(Vickers Preliminary Technical Leaflet No. 225 and Modification D.3000 cover this subject.)

This directive effective March 3, 1961.

*Whenever a brake unit is reassembled or initially installed on the ram foot, precautionary measures as detailed in Vickers PTL No. 225 should be observed.