Pratt & Whitney's (P&W) newest engine, the F100-PW229A for F-15 and F-16 fighter aircraft, has demonstrated "unprecedented" performance in recent altitude tests, running at Mach 2.0. Under development for six years, the engine already has been tested to Mach 2.3 at 40,000 ft simulated altitude, and logged over 450 test hrs. The latest tests were to qualify production fan aerodynamics. "This is a fully configured engine under test, not one made up of components assembled for testing purposes," notes Dennis Enos, P&W's F100 program director. A key difference between this engine and other F100s that power operational F-15 and F-16 fighter aircraft is that it uses an advanced aerodynamic fan derived from F119 engine technology P&W developed for the F-22 Raptor. The robust design fan with its cast, one-piece inlet case exceeds air flow, efficiency, and stall margin requirements, Enos adds. P&W reports that the design represents the first military fighter engine not to require variable fan inlet geometry. FAX (407) .