In January 1983, the Naval Air Systems Command authorized a coordinated NAVAIRTESTCEN/Lockheed study to establish the feasibility of a low-cost procedure for monitoring U.S. Navy P-3C T56-A-14 engine performance from inflight recorded cockpit instrumentation. The resulting study, still in progress, was organized into three phases. In the first phase, a flight test program was conducted to obtain actual engine performance data from which performance standards or baselines could be developed. In the second phase, algorithms and procedures for implementing inflight engine performance trending were established. Finally, in January of 1984 a fleet trial was initiated. This paper discusses the user's motivation for such a system, describes the flight test program and associated analyses, outlines the proposed engine monitoring system, and concludes with a status report on the ongoing fleet trials.