Airworthiness Directives; Piper Aircraft, Inc. Model PA-28-161 Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above that are equipped with Thielert Aircraft Engine GmbH (TAE) Engine Model TAE-125-01 installed per Supplemental Type Certificate (STC) No. SA03303AT. This AD requires installing a full authority digital engine control (FADEC) backup battery, replacing the supplement pilot's operating handbook and FAA approved airplane flight manual, and revising the limitations section of the supplement airplane maintenance manual. This AD was prompted by an incident where an airplane experienced an in-flight engine shutdown caused by a momentary loss of electrical power to the FADEC. We are issuing this AD to prevent interruption of electrical power to the FADEC, which could result in an uncommanded engine shutdown. This failure could lead to a loss of engine power.