67-01-03 PRATT & WHITNEY: Amdt. 39-336 Part 39 Federal Register January 4, 1967. Applies to Model JT4A Series Turbojet Engines.
Compliance required as indicated unless already accomplished.
To prevent failure of the fuel manifold assembly, accomplish the following:
(a) Within the next 3,400 hours' time in service after the effective date of this AD, inspect all P/N's 378155, 378156, 391957, 391959, 447330 and 447339 fuel manifold assemblies for cracks using the fluorescent penetrant inspection procedures outlined in Pratt & Whitney Aircraft JT4A Overhaul Manual.
(1) If cracks are found, replace before further flight the fuel manifold assembly with one of the fuel manifold assemblies listed above or with a P/N 572766 or 572767 fuel manifold assembly.
(2) If no cracks are found, glass bead peen all cluster tee fillets (eight places per each fuel manifold assembly) prior to return to service and thereafter at each fuel mainfold assembly overhaul in accordance with Pratt& Whitney Aircraft JT4A Overhaul Manual Temporary Revision No. 73-9 dated October 20, 1966, or Pratt & Whitney Aircraft JT4A Overhaul Manual Revision No. 39 which includes Temporary Revision No. 73-9.
(b) At each fuel manifold assembly overhaul, inspect and glass bead peen in accordance with (a) all fuel manifold assemblies P/N's 572766 and 572767.
NOTE: Fuel Manifold Assemblies P/N's 572766 and 572767 were glass bead peened during initial fabrication.
(c) Prior to use, inspect and glass bead peen in accordance with (a) all spare fuel manifold assemblies P/N's 378155, 378156, 391957, 391959, 447330, and 447339.
(Pratt & Whitney Aircraft letter dated March 23, 1966, to all operators of JT4A turbojet engines covers this subject.)
This directive effective January 5, 1967.