72-16-09 HUGHES: Amendment 39-1497. Applies to Hughes Model 369A and 369H Series Helicopters certificated in all categories.
Compliance required as indicated.
To prevent possible failure of the input gearshaft assembly, accomplish the following:
(a) For those helicopters incorporating tail rotor input gearshaft assemblies (see NOTE for P/N's) which have accumulated 2,000 hours' or more time in service on the effective date of this AD, accomplish (c) and (d), below, unless already accomplished, prior to further flight.
(b) For those helicopters incorporating tail rotor input gearshaft assemblies (see NOTE for P/N's) which have accumulated 1,800 hours' or more time in service on the effective date of this AD, accomplish (c) and (d), below, within 100 additional time in service, unless already accomplished. If the additional time in service would result in a total time in service in excess of 2000 hours, the 100 hours' compliance time shall be reduced by that amount necessary to prevent any tail rotor input gearshaft assemblies from being operated beyond 2000 hours before accomplishment of this AD.
(c) Revise the helicopter logbook, as applicable, to record both the input and the output gearshaft assemblies incorporated in the 369A5406 tail rotor gear set, per the instructions of Part I of Hughes Service Information Notice No. HN-53, dated July 24, 1972, or later FAA approved revisions.
(d) Retire and replace the 369A5425 and 369A5425-3 input gearshaft assemblies (input part of 369A5406 gearset), per the instructions of Part II of Hughes Service Information Notice No. HN-53, dated July 24, 1972, or later FAA approved revisions. Owners and operators may exercise the options specified in Part II of the Notice.
NOTE: The part number assemblies and finite life are:
TAIL ROTOR INPUT
FINITE
GEARSHAFT ASSEMBLY
LIFE
P/N 369A5406 (input only)
1,800 hours
P/N 369A5425, -3
1,800 hours
P/N 369A5425-5
27,600 hoursNOTE: The P/N 369A5406 tail rotor gearset is comprised of an input gearshaft assembly and a pinion output gearshaft assembly. The finite life of all existing pinion output gearshaft assemblies remains unchanged at 2,940 hours.
This amendment becomes effective August 8, 1972.