The FAA has issued an Airworthiness Directive for Thielert Aircraft Engines GmbH (TAE) Models TAE 125–01 and TAE 125–02–99 because in-flight shutdowns have been reported on some of the engines.
Preliminary investigations showed that it was mainly the result of nonconforming disc springs (improper heat treatment) used in a certain production batch of the clutch, according to the FAA, which notes, “We are issuing this AD to prevent engine in-flight shutdown leading to loss of control of the airplane.”
The AD becomes effective Sept. 9. The FAA is accepting comments on it until Sept. 24. The European Aviation Safety Agency (EASA) issued its own AD earlier this summer after Germany-based TAE issued a Service Bulletin.
The AD requires owners of the engines “before the next flight after the effective date of this AD, identify the serial number (S/N) of each P/N 02–7210–11001R13, P/N 05–7211–K006001, and P/N 05–7211–K006002 clutch assembly installed on the airplane. If the S/N matches one of those listed in Thielert Aircraft Engines GmbH Service Bulletin (SB) No. TM TAE 125–0021, dated June 9, 2010, or SB No. TM TAE 125–1011 P1, dated June 9, 2010, replace the clutch assembly within the following compliance times: For engines with affected clutch assemblies that have accumulated 100 flight hours or more on the effective date of this AD, replace the clutch assembly before further flight. For engines with affected clutch assemblies that have accumulated less than 100 flight hours on the effective date of this AD, replace the clutch assembly before accumulating 100 flight hours.”
For more information: FAA.gov.