AD/HU 369/97 - Overrunning Clutch Assembly (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

McDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters

AD/HU 369/97 Overrunning Clutch Assembly 14/98

DM

Applicability: Model 369D, 369E, 369FF, 500N, AH-6 and MH-6 helicopters fitted with overrunning clutch assembly, part number (PN) 369F5450-501

Requirement: Visually inspect the overrunning clutch retainer, P/N 269F5460-1, carrier, P/N 369F5461-1, housing, P/N 369F545-1, and pin, P/N MS16556-801, for clutch or carrier wear or pin damage in accordance with the Accomplishment Instructions in McDonnell Douglas Helicopter Service Information Notice No. DN-190, EN-83, FN- 70, NN-011, dated 25 July 1997.

Note: FAA AD 98-21-12 refers.

Compliance: From the effective date of this AD:

1. For clutch assemblies having less than 100 hours Time-in-Service (TIS), conduct the visual inspection before or upon reaching 100 hours TIS.

b. For clutch assemblies with having 100 or more hours TIS, conduct the visual inspection within 25 hours TIS.

c. Repeat the requirement at intervals not exceeding 100 hours TIS.

Note: For the purpose of this Directive, TIS is the time in service since new or last overhaul.

d. If at any time the required inspections reveal wear or damage to components, replace those components with airworthy components prior to further flight.

This Airworthiness Directive becomes effective on 4 November 1998.

Background: A visual inspection is required for the components specified in the requirement section of this AD. An operator in the USA had experienced inflight vibrations and subsequent inspection found wear of the bearing retainer and outer race of the bearing. Inspections of three other overrunning clutches with the same P/N also indicated spinning of the retainer. This condition, if not corrected, could ultimately lead to loss of power to the rotor drive system.