51-03-02 MARTIN: Applies to All Models 202 and 202A Aircraft.
Compliance required by April 1, 1951, on all aircraft having main landing gears with 4,000 hours service or more, and thereafter every 4,360 cycles of landing gear operation.
Due to reported occurrences of cracks, the main landing gear crankshafts (P/N 202SD82019 and 202SD82021) should be replaced with new crankshafts bearing the same part numbers and having a ground radius around the periphery of the hole for the retract pin.
(Martin Service Bulletin No. 128, dated October 4, 1950, covers this same subject.)