Airworthiness Directive · Amendment 39-11690 · Robinson Helicopter Company Model R44 Helicopters
Robinson Helicopter Company Model R44 Helicopters
Model R44 Helicopters, serial number (S/N) 0001 through 0541, inclusive, 0543, 0550, 0556, and 0565 with sprag clutch, part number (P/N) C188-3, S/N 0003 through 0505, inclusive, installed, certificated in any category.
Note 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD), applicable to Robinson Helicopter Company (RHC) Model R44 helicopters. This action requires replacing certain serial number (S/N) sprag clutches with an airworthy sprag clutch as specified in this AD. This amendment is prompted by several reports of sprag clutch failures. The actions specified by this AD are intended to prevent a sprag clutch failure, loss of main rotor RPM during autorotation, and subsequent loss of control of the helicopter.
To prevent sprag clutch failure, loss of main rotor RPM during autorotation, and subsequent loss of control of the helicopter, accomplish the following:
(a) Replace sprag clutch, P/N C188-3, S/N 0003 through 0505, inclusive, with sprag clutch P/N C188-3, S/N 0506 or higher.
(b) Remove from the Rotorcraft Flight Manual the Special Pilot Caution, dated March 22, 1999, contained in Robinson Helicopter Company R44 Service Bulletin SB-32 dated March 22, 1999, or the Special Pilot Caution insert in the Normal Procedures Section of the Rotorcraft Flight Manual between pages P.4-8 and P.4-9 required by AD 99-07-18, Docket No. 99-SW-25-AD, Amendment 39-11127 (64 FR 17964, April 13, 1999), as applicable.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
