65-22-03 MOONEY: Amdt. 39-138 Part 39 Federal Register September 16, 1965. Applies to Models M20 and M20A Airplanes.
Compliance required within the next 25 hours' time in service after September 16, 1965, unless already accomplished within the last 75 hours' time in service, and thereafter at intervals not to exceed 100 hours' time in service from the last inspection until tail truss, Mooney P/N 4009, is replaced with tail truss, Mooney P/N 48007, in accordance with Mooney Service Bulletin No. 20-138 or later FAA-approved revision.
To prevent further cracking in the tubular steel tail truss that supports the empennage on airplanes with wood wings and wood empennage, accomplish the following:
(a) Remove sheet metal fairings over tail truss, remove and disassemble empennage, and remove tail truss. Inspect visually for cracks all welded joints and adjacent structures in tail truss, P/N 4009, using at least a 10-power glass or FAA-approved equivalent.
(b) If cracks are foundin U-fitting, P/N 4010, at the lower forward end of the truss, repair before further flight in accordance with Mooney Service Letter No. 20-68 or later FAA- approved revision or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Southwest Region.
(c) If cracks are found in the tail truss within 0.50 inch of an existing weld bead except in U-fitting, P/N 4010, repair before further flight in an FAA-approved manner flame annealing any area where old and new welds join.
(d) If cracks are found in the tail truss 0.50 inch or more from an existing weld bead except in U-fitting, P/N 4010, before further flight -
(1) Replace the tail truss with an unused part of the same part number or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Southwest Region; or
(2) Repair it in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Southwest Region or by a Mooney Aircraft, Inc., Designated Engineering Representative.
(Mooney Service Letters Nos. 20-30, 20-49, and 20-49A also pertain to this subject.)
This directive effective September 16, 1965.
Revised November 4, 1965.
Revised August 20, 1966.