Airworthiness Directives; Austro Engine GmbH Engines

The FAA is adopting a new airworthiness directive (AD) for certain Austro Engine GmbH E4 and E4P model diesel piston engines. This AD was prompted by reports of failure of the high-pressure pump (HPP) driving gear and a subsequent determination that a batch of HPP driving gears may have been damaged during assembly. This AD requires, for engines with an affected cylinder head, inspection of the HPP driving gear and, depending on the results of the inspection, replacement of the HPP driving gear with a part eligible for installation. This AD also requires, for engines with an affected HPP driving gear, replacement of the HPP driving gear either before further flight or within a certain number of flight hours after the effective date of this AD. The FAA is issuing this AD to address the unsafe condition on these products.