75-17-31 MCDONNELL DOUGLAS: Amendment 39-2319. Applies to all DC-8 Series airplanes as listed on McDonnell Douglas DC-8 Service Bulletin 32-168, Rev. 2 dated July 25, 1975, or later FAA-approved revisions, and certificated in all categories. \n\n\tCompliance required as indicated. \n\n\tTo prevent failure of the Nose Landing Gear (NLG) orifice support tube from fatigue and possible nose gear collapse, accomplish the following: \n\n\t(a)\tWithin the next 1000 landings after the effective date of this AD, unless already accomplished, remove the NLG orifice support tube P/N 5598184 or 5717019 and perform a penetrant inspection of the upper O-ring groove in accordance with McDonnell Douglas DC-8 Service Bulletin 32-168, Rev. 2 dated July 25, 1975, or later FAA-approved revisions, or by an equivalent inspection procedure approved by the Chief, Aircraft Engineering Division, FAA Western Region. \n\n\t\t(1)\tIf cracks are found, discard the support tube and either replace with a reworked orifice support tube, P/N 5598184-SC2465 or 5717019-SC2465 or replace with a new orifice support tube, P/N 5598184-503 or 5717019-503, in accordance with DC-8 Service Bulletin 32-168, Rev. 2 dated July 25, 1975, or later FAA approved revision, or an equivalent rework approved by the Chief, Aircraft Engineering Division, FAA Western Region. \n\n\t\t(2)\tAll tubes found to be free of cracks must either be reworked and replaced in accordance with DC-8 Service Bulletin 32-168 Rev. 2 dated July 25, 1975, or later FAA-approved revisions, or an equivalent rework procedure approved by the Chief, Aircraft Engineering Division, FAA Western Region, or they must be replaced by new orifice support tubes, P/N 5598185-503 or 5717019-503. \n\n\t(b)\tUnless already accomplished by (a)(1) or (a)(2), above, within the next 8000 landings after the installation of reworked orifice support tube, replace with a newly reworked tube, P/N 5598184-SC2465 or 5717019-SC2465, or with a new orifice support tube, P/N 5598184-503 or 5717019-503, in accordance with DC-8 Service Bulletin 32-168, Rev. 2 dated July 25, 1975, or later FAA-approved revisions. \n\n\tUpon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Aircraft Engineering Division, FAA Western Region, may adjust the initial inspection compliance time specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. \n\n\tThis amendment becomes effective August 20, 1975.