68-14-02\tBOEING: Amendment 39-620. Applies to all Model 727 Series Airplanes. \n\n\ta.\tUnless already accomplished, within the next 250 hours time in service after the effective date of this AD, install in each main landing gear downlock actuating system, a torque tube assembly, Boeing P/N 65-26921 in which the brazed joint at each end has been inspected and found to be acceptable in the manner described in Boeing Alert Service Bulletin No. 32-160 dated July 1, 1968, or later FAA-approved revision, or which has been modified to incorporate special structural fasteners in the locations and in the manner described in that Bulletin or in another manner approved by the Chief, Aircraft Engineering Division, FAA Western Region. \n\n\tb.\tPrior to return to service following the replacement of any torque tube assembly, Boeing P/N 65-26921, inspect the replacement assembly of the same part number in the manner described in Boeing Alert Service Bulletin No. 32-160 dated July 1, 1968, or laterFAA-approved revision, unless the assembly has been modified to install structural fasteners in the manner prescribed in a., above, or unless there is conclusive evidence that the assembly has been inspected in the manner described in Boeing Service Bulletin No. 32-160 dated July 1, 1968, or later FAA-approved revision, and found to be satisfactory. \n\n\tNOTE. Conclusive evidence may consist of markings or other identification placed on the assembly by the airplane manufacturer or airplane operator, when it is known that such marking or identification verifies compliance with the prescribed inspection and acceptance requirement. \n\n\tc.\tAirplanes inspected and found to have downlock torque tube assemblies with unacceptable brazed joints may be flown in accordance with FAR 21.87 and with landing gear extended and locked to a base where replacement or modification of the torque tube assembly can be accomplished. \n\n\tThis amendment becomes effective July 11, 1968.