64-10-01 BOEING: Amdt. 723 Part 507 Federal Register May 2, 1964. Applies to Models 707 and 720 Series Aircraft, Serial Numbers 17586 through 17628, 17630 through 17632, 17634 through 17640, 17642 through 17652, 17658 through 17690, 17692 through 17710, 17718 through 17720, 17722 through 17724, 17903 through 17906, 17908 through 17930, 18012 through 18019, on Which Boeing Service Bulletin No. 942 or an FAA Approved Equivalent Has Not Been Accomplished.\n \n\tCompliance required as indicated, unless already accomplished. \n\n\tBecause of recently discovered cracks in the stabilizer center section rear spar fitting, accomplish the following inspections and modification: \n\n\t(a) Within 125 hours' time in service after May 2, 1964, for all affected aircraft except aircraft with Serial Numbers 17658 through 17690, and within 125 hours' time in service after the effective date of this amendment for aircraft with Serial Numbers 17658 through 17690, remove upper left-hand and right-hand rear stabilizer attach pins. Inspect pins and holes in fitting lugs for cracks, by magnetic particle or dye penetrant method. Clean up any corrosion on pins and lugs. Replace any cracked part before further flight. (Boeing Service Bulletin No. 1967 (R-1) covers this same subject.) \n\n\t(b) Within 550 hours' time in service after May 2, 1964, for all affected aircraft except aircraft with Serial Numbers 17658 through 17690, and within 550 hours' time in service after the effective date of this amendment for aircraft with Serial Numbers 17658 through 17690, and at intervals not to exceed 1,650 hours' time in service from the last inspection, until (c) is accomplished, remove all stabilizer attach pins. Inspect pins and holes in fitting lugs for cracks, by magnetic particle or dye penetrant method. Clean up any corrosion on pins and lugs. Regrease pins with MIL-G-7118 grease and reinstall. Install cadmium plated pins only, unless chrome plating is required to build up pin diameter.Replace any cracked part before further flight. (Boeing Service Bulletin No. 1967 (R-1) covers this same subject.)\n \n\t(c) Within 5,000 hours' time in service after the effective date of this AD, remove left- hand and right-hand stabilizers and ream the terminal fittings on the stabilizers and torque box. Install bushings in the reamed holes according to Boeing Service Bulletin No. 942 or an FAA approved equivalent. (Boeing Service Bulletin No. 942 covers this same subject.) \n\n\tNOTE. - This AD supplements AD 64-04-02, concerning the same subject issued on February 4, 1964, and does not cancel nor supersede that AD. \n\n\tThis directive effective May 2, 1964. \n\n\tRevised August 12, 1964.