68-02-05 MCDONNELL DOUGLAS: Amdt. 39-559. Applies to Model DC-9 Series airplanes. \n\n\tType Certificate Data Sheet No. A6WE, Revision 5, established a service life limit of 26,700 landings for the Nose Landing Gear Shock Strut Restrictor Assembly which is a component of the Nose Landing Gear Cylinder Assembly on DC-9 Series airplanes. The Nose Landing Gear Shock Strut Restrictor Assembly is available under three (3) part numbers. P/N 5958435-501 (Models DC-9-11, -12, -13, -14, -15 and -15F) and P/N 5920616-1 (Models DC-9-31, 32 and -32F) have a 3/8-inch hole near the packing groove at the upper end of the support assembly and are affected by this AD. The third part, P/N 5958435-1 (Models DC-9-11, -12, -13, -14, -15 and -15F) which has no hole, is not affected by this AD. \n\n\tAs a result of further fatigue testing, McDonnell Douglas has established a new service life limit of 8,000 landings for P/N 5958435-501 and P/N 5920616-1 due to fatigue failure in the vicinity of the hole. \n\n\tLater revisions of Type Certificate Data Sheet No. A6WE will list the new service life limit for these parts. \n\n\tTo prevent fatigue failure: \n\n\tAs of the effective date of this AD, the service life limit of P/N 5958435-501 and P/N 5920616-1 Nose Landing Gear Shock Strut Restrictor Support Assembly is 8,000 landings. \n\n\tThis amendment becomes effective on February 29, 1968.