Summary
We propose to adopt a new airworthiness directive (AD) for all Thielert Aircraft Engines GmbH TAE 125-01 reciprocating engines. This proposed AD was prompted by a report of engine power loss due to engine coolant contaminating the engine clutch. The design of the engine allows the crankcase assembly opening to be susceptible to contamination from external sources. This proposed AD would require applying sealant to close the engine clutch housing (crankcase assembly) opening. We are proposing this AD to prevent in-flight engine power loss, which could result in loss of control of, and damage to, the airplane.