Actually, what saved the TriStar program was Rolls-Royce offering the much more powerful Trent 700 engine, which made it possible for Lockheed to build a twin-engine version of the plane by 1988. The L-1022, as the plane is known today, built with ETOPS certification in mind and had ranges of 5,600 nautical miles for L-1022-200 longer version and 6,400 nautical miles for the L-1022-100XR shorter version (OOC: it duplicated what Airbus did with the A330), and Lockheed couldn't keep up with demand.