Among the large turbofan engines being developed for commercial applications is the General Electric CF6—80C for which certification is scheduled for June, 1985. Testing began this year and a thrust rating of 56,000 lb. is anticipated on entry into service with potential for further increases up to 62,0001b. Expected engine performance criteria have been met or exceeded on test, with temperatures, pressures and stresses as predicted and the new active clearance control system in the HP turbine having demonstrated its ability to reduce the sfc. The CF6—80C is being proposed as a powerplant for the Airbus A300–600, the stretched upper deck Boeing 747–300, advanced versions of the Boeing 767, the McDonnell Douglas DC‐10–30 and a number of military applications.