Research and development of advanced high-temperature Air Force turbine engine oil©

Military and commercial jet aircraft engines operate more efficiently and hotter than in the past to increase fuel efficiency. Advanced structural engine materials permit hotter burning, more efficient engines. These trends will continue. Many current gas turbine engines are experiencing oil system coking and other problems related to the limited thermal and oxidative stability of the conventional, ester-based gas turbine engine oils. The best current oils have a maximum operating temperature of about 200 degrees C. The authors initiated a program to develop a new class of ester-based lubricants to meet their high-temperature requirements. The rat-get temperature range of this new oil is -40 degrees to 232 degrees C. Target requirements were established and communicated to industry. This paper presents those requirements and initial results on the most promising candidates.