GM and UTC are working on an engine.

General Motors and United Technologies Corp. have formed a company, PW-Allison Engines, to build a new propeller-driven engine for a future generation of commercial aircraft, the companies said. The Prop-Fan engine will be as fast as a commercial jet aircraft engine but will be quieter, use 30% less fuel and require less runway for takeoff and landing, GM said. The firm will build a demonstration version of the engine on a McDonnell Douglas MD-80 plane by the end of 1987, the companies said.