Airworthiness Directive · Amendment 39-10028 · Sikorsky Aircraft-Manufactured Model S- 64F Helicopters
Sikorsky Aircraft-Manufactured Model S- 64F Helicopters
Superseded. A later AD replaced this one: AD 2012-26-06. Comply with the one in force.
Sikorsky Aircraft-manufactured Model S-64F helicopters, with main gearbox second stage lower planetary plate, part number (P/N) 6435-20516-101, installed, certificated in any category.
This amendment adopts a new airworthiness directive (AD), applicable to Sikorsky Aircraft-manufactured Model S-64F helicopters, that requires inspections, and replacement, if necessary, of the main gearbox second stage lower planetary plate (plate). This amendment is prompted by two incidents in which the plate was found cracked. The actions specified by this AD are intended to prevent failure of the plate due to fatigue cracking, which could lead to failure of the main gearbox and subsequent loss of control of the helicopter.
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
