Airworthiness Directive · Amendment 39-17736 · Tail rotor system
Agusta S.p.A. (Type Certificate Currently Held by AgustaWestland S.p.A.) (Agusta) Helicopters
Superseded. A later AD replaced this one: AD 2015-11-08. Comply with the one in force.
This AD applies to Agusta Model A109C, A109S, and A109K2 helicopters, all serial numbers; Model A109E helicopters, serial number (S/N) 11002 through 11807 except S/N 11796; and Model AW109SP helicopters, S/N 22202 through 22278, except S/N 22239, 22264, 22266, 22272, 22273, 22275, and 22277, certificated in any category.
We are adopting a new airworthiness directive (AD) for certain Agusta Model A109C, A109E, A109S, A109K2, and AW109SP helicopters. This AD requires inspecting the lock wires securing the tail rotor (T/R) duplex bearing locking nut (locking nut) to determine whether any lock wires are missing or damaged. This AD was prompted by reports of loosening T/R locking nuts. The actions of this AD are intended to prevent failure of the T/R and subsequent loss of control of the helicopter.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(1) Within 5 hours time-in-service (TIS), inspect each lock wire securing the T/R locking nut to the housing.
(i) If only one lock wire is installed and it is not damaged, before further flight, install a second lock wire.
(ii) If one or both lock wires are installed, and either one or both are damaged, before further flight, remove and reassemble the housing and slider group of the T/R rotating controls.
(2) Within 25 hours TIS from the inspection required by paragraph (e)(1) of this AD, and thereafter at intervals not exceeding 25 hours TIS, inspect the lock wires which secure the T/R locking nut to the housing. If either lock wire is missing or damaged, before further flight, remove and reassemble the housing and slider group of the T/R rotating controls.
(3) Within 100 hours TIS, remove and reassemble the housing and slider group of the T/R rotating controls.
(4) Removing and reassembling the housing and slider group of the T/R rotating controls as required by paragraph (e)(1)(ii), (e)(2), or (e)(3) is terminating action for this AD.
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.
