Engine Overhaul Could Save Billions of Dollars

The Air Force and Navy could save more than $2 billion by modifying CFM International’s CFM56-2 (F108) engine that powers KC-135 tankers, RC-135 reconnaissance aircraft, and Navy E-6B Mercury command and control airplanes, according to Navy officials. The modifications are expected to restore exhaust gas temperature margins, increase fuel economy, and extend the time needed between overhauls from 10 years to 15 years, they said in a May 23 release. “As incredible as these achievements are, both the Navy and the Air Force were struggling to reclaim lost engine efficiency,” said Andy Noble, Navy CFM56 propulsion manager. “In our case, only half of the engine life was being regained after the first overhaul. We could not gain back the performance we saw with the original engine build.” After four rounds of extensive ground testing and flight tests, the Federal Aviation Administration is expected to certify the engine modifications by the end of May, it states. (Patuxent River report by Rob Koon)