Abstract
Reliability and serviceability of jet engines in the aviation industry is of paramount importance and is directly related to flight safety. Tight maintenance programs, including scheduled and preventive inspection are in place worldwide for jet engines to ensure air worthiness of aircraft. Old age provides maintenance maturity to the system, but on other hand, it requires focused efforts to ensure reliability due to aging factor. J69-T-25A falls in the same category, as it has been in service for the last six decades. Despite all maintenance efforts, a variety of defects are being faced on J69 engines. The major defects include RPM fluctuation, noise, oil gain, vibration, and smoke. The troubleshooting process identifies a number of components that cause these problems. this chapter is based on statistical analyses of component failure in terms of frequency and fault isolation. The top ten components were selected based upon failure rates and were compared against reported problems to establish a relationship between defects and failed components. Based upon the result, various remedial measures are suggested to reduce defects in the future and increase engine reliability.