82-24-01: Drivebelt Clutch Mechanism

82-24-01 ENSTROM HELICOPTER CORPORATION: Amendment 39-4497. Applies to Model F-28A, F-28C, F-28F, 280, 280C, and 280F helicopters certificated in all categories. Compliance required as indicated unless already accomplished. To prevent possible in-flight drivebelt clutch disengagement, accomplish the following: (a) Before further flight after the effective date of this AD, and thereafter at intervals not to exceed 100 hours' time in service from the last inspection: (1) Inspect the drivebelt clutch mechanism, in accordance with Enstrom Service Information Letter 0080, Revision A, dated August 4, 1982, or FAA approved equivalent, and the Maintenance/Manual Supplement for the respective Models, to ascertain that the mechanism is properly rigged. NOTE: When properly rigged the clutch actuating cable should move freely allowing full clutch engagement. Clutch mechanisms experiencing binding of the clutch actuating cable, although properly rigged and lubricated, may have lubricant hardened in the cable assembly due to engine heat. (2) Replace any cable found to bind, preventing full clutch engagement, prior to further flight with suitable airworthy parts. (3) Lubricated the clutch actuating cable with Aero Shell 14 or FAA approved equivalent. (b) Within the next 25 hours' time in service after the effective date of this AD, unless already accomplished, install clutch cable heat shield P/N 28-16542-11 in accordance with Enstrom Service Directive Bulletin 0055, Revision A, dated April 2, 1982, or FAA approved equivalent. NOTE: Enstrom Helicopter Models equipped with right pilot-in-command kits P/N 28- 01002 or P/N 28-01012; or electric clutch actuator kit P/N 28-01005 are exempt from this paragraph. (c) Within the next 50 hours' time in service after the effective date of this AD, unless already accomplished, install clutch engagement overcenter lock warning light kit P/N 28- 19035-3 in accordance with EnstromService Directive Bulletin 0061 dated September 20, 1982, or FAA approved equivalent. (d) Any equivalent method of compliance with this AD must be approved by the Manager, Chicago Aircraft Certification Office, Federal Aviation Administration, 2300 East Devon Avenue, Des Plaines, Illinois 60018. (e) In accordance with FAR 21.197, flight is permitted to a base where the inspection required by this AD may be accomplished. This amendment becomes effective November 30, 1982.