54-24-03 LOCKHEED: Applies to All Models 49, 149, 649, 749, and 1049 Aircraft.
Compliance required no later than the next regularly scheduled landing gear overhaul for all subject type aircraft.
Failures of Bendix No. 405308 main landing gear actuating cylinder assembly are continuing to occur and may result in flight hazards due to inability to actuate the landing gear. Bendix Pacific Division issued their Service Bulletin No. 71 dated December 26, 1952, for rework and inspection of these assemblies. Lockheed has written to all operators, August 20, 1954, specifying additional rework.
It is necessary, in order to increase service life of these cylinders, to either replace them with cylinders of the new Bendix design (which incorporate a 3/16-inch radius in the barrel) or to accomplish the following:
1. Rework cylinder assemblies 405308-0-1, -0-2, -0-3, -0-4, -0-5 and -1 to provide a 3/32-inch relief radius at the juncture of the barrel bore relief area and bottom of the barrel, and to spot-peen this 3/32-inch radius area.
2. Magnetically inspect the barrel internally and externally prior to and following the rework per item 1. If the barrel is cracked, it must be scrapped.
(Bendix Service Bulletin No. 71 and Lockheed Letter FS/93931 to operators dated August 20, 1954, covers this same subject.)