54-05-01 CURTISS-WRIGHT: Applies to all C-46 Series aircraft equipped with Landing Gear Retraction Cylinder Heads, Curtiss-Wright P/N S20-313-3044. \n\n\tCompliance required as soon as practicable but not later than July 15, 1954.\n \n\tAs a result of several failures of the landing gear retraction cylinder head emanating from fatigue cracks occurring in the radius of the O ring groove, it has been found necessary to inspect and rework the landing gear retraction cylinder head to provide a more serviceable part. \n\n\tRemove the landing gear retraction cylinder head and inspect the upper and lower radii of the O ring groove for cracks by means of a dye penetrant. If cracks are found the part should be replaced. In the event no cracks are present the upper and lower radii of the O ring groove should be increased to 0.040 inch as shown in Figure 4 and again inspected by means of a dye penetrant. If no cracks are found after this inspection, the part may be returned to service; however,if cracks are evident, the part should be replaced. \n\n\n\n\tNote: Smooth machine finish (RMS-32 or better) with no tool marks or discontinuities. No change in size of O ring necessary.