Airworthiness Directive · Amendment 39-11089 · Dr.Ing.h.c.F. Porsche Aktiengesellschaft (Porsche) 3200N01, N02, and N03 Reciprocating Engines
Dr.Ing.h.c.F. Porsche Aktiengesellschaft (Porsche) 3200N01, N02, and N03 Reciprocating Engines
Porsche PFM3200N01, N02, and N03 reciprocating engines, installed on but not limited to Mooney M20L series airplanes.
This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 99-04-15 that was sent previously to all known U.S. owners and operators of Porsche PFM3200N01, N02, and N03 reciprocating engines by individual letters. This AD requires replacement of valve springs prior to further flight on PFM3200N01, N02, and NO3 engines. This amendment is prompted by reports of six cases of undetected fatigue failures of valve springs, with one valve spring failure causing an in-flight engine failure that ended in an emergency landing. The actions specified by this AD are intended to prevent an in-flight engine shutdown due to undetected fatigue failures of valve springs.
