A major milestone for the Boeing Longer-Range 767-400ER (extended range) program was met this week when low-speed wind-tunnel testing was completed at the University of Washington in Seattle. Boeing engineers, shown here, used a 5.5- percent scale model to test the effect of wind speed on the engine's nacelles. The nacelles on the Longer-Range 767-400ER are 20 percent larger than those on the 767-200ER, 767-300ER and 767-400ER airplanes. The Longer-Range 767-400ER will have new and more powerful 72,000-pound (32,659 kg)-thrust engines that are being developed by Rolls Royce and the Engine Alliance, a joint company of GE Aircraft Engines and Pratt & Whitney. The engines also will be used on the 747X family of airplanes.