64-18-04 GENERAL DYNAMICS: Amdt. 778 Part 507 Federal Register July 29, 1964. Applies to Models 240, 340 and 440 Series Aircraft Incorporating Nose Landing Gear Retract Fork, Menasco P/N 523526 R/L.
Compliance required as indicated.
In order to detect cracks and prevent the failure of the nose landing gear retract fork, Menasco P/N 523526 R/L, accomplish the following:
(a) Within 800 hours' time in service after the effective date of this AD, unless already accomplished within the last 200 hours' time in service, and thereafter at periods not to exceed 1,000 hours' time in service from the last inspection, inspect all nose landing gear retract forks, Menasco P/N 523526 R/L, for cracks in the 0.190 (+0, -.030) inch radius at the upper end of the fork shank diameter using dye penetrant, magnetic particle, or an FAA approved equivalent inspection, and dimensionally inspect for a 0.190 (+0, -.030) inch radius. Any fork having less than 0.160 inch minimum radius shall havethe radius hand reworked to a 0.190 (+0, - .030) inch radius. (Care should be taken that the adjacent 1.2500/1.2495 inch diameter is not undercut.) Refinish the reworked area in accordance with the instructions contained in Convair Service Airgram No. 179, dated June 18, 1956, or an FAA Western Region, Aircraft Engineering Division approved equivalent. If cracks are found in either half of the fork assembly, remove and replace the complete fork assembly with a new fork assembly before further flight.
(b) The repetitive inspections specified in (a) may be discontinued when the fork assembly has been reworked to the 0.190 (+0, -.030) inch radius, and has been shot peened and refinished in accordance with the instructions contained in Convair Service Airgram No. 179, dated June 18, 1956, or an FAA Western Region, Aircraft Engineering Division approved equivalent.
(c) Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Aircraft Engineering Division, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator.
(Convair Service Airgram No. 179 dated June 18, 1956, covers this same subject.)
This directive effective August 28, 1964.