68-12-05 AERO COMMANDER: Amdt. 39-611. Applies to Models 100 and 100A, and Volaire Models 10A and 10, Serial Numbers 001 through 250.
Compliance required as indicated.
To preclude failure of the left and right arms, P/N 35321, of the rudder control system, accomplish the following:
NOTE: The arms are those to which the rudder system left and right cables and springs are attached, and extend forward from the cross-bar assembly supporting the rudder pedals.
(a) Within the next 10 hours' time in service after the effective date of this AD, unless already accomplished, inspect and modify the left and right arms, P/N 35321, as follows:
Clean to bare metal all surfaces of the web and flanges of each arm over an area extending from the center of the 3/16 inch diameter cable attach hole to a point 3/4 inch aft of the hole. Visually inspect the exposed areas of the webs for cracks using a 10-power magnifying glass, or in an equivalent manner approved by the Chief,Engineering and Manufacturing Branch, FAA Southern Region. Weld the 1/16 inch deep square notches which are located in the webs at the forward ends of the upper and lower flanges of each arm, completely filling the notches with weld metal. Weld all cracks detected during the inspection with full penetration welds over the full length of each crack. Recoat the exposed area with oxide primer or equivalent.
(b) Within the next 25 hours' time in service after the effective date of this AD, unless already accomplished, modify the left and right arms, P/N 35321, in accordance with the instructions contained in Aero Commander Service Bulletin 1009, dated May 24, 1968, or in an equivalent manner approved by the Chief, Engineering and Manufacturing Branch, FAA Southern Region.
This amendment becomes effective June 14, 1968.