Airworthiness Directives; Agusta S.p.A. Helicopters
We are adopting a new airworthiness directive (AD) for Agusta S.p.A. (Agusta) Model AB412 and AB412EP helicopters with a certain rotor brake pinion installed. This AD requires inspecting the rotor brake pinion for a crack, and replacing it if there is a crack. This AD is prompted by a report of a rotor brake pinion failure. These actions are intended to detect a crack on the rotor brake pinion and prevent failure of the rotor brake pinion, which could lead to detachment of parts inside the transmission and subsequent loss of control of the helicopter.