The F-35 Joint Strike Fighter flew supersonic for the first time yesterday, achieving another milestone. The aircraft accelerated to Mach 1.05, or about 680 miles per hour. The test validated the F-35 Lightning II's capability to operate beyond the speed of sound and was accomplished with a full internal load of weapons on the one-hour flight. "The F-35 transitioned from subsonic to supersonic just as our engineers and our computer modeling had predicted," said Jon Beesley. "I continue to be impressed with the aircraft's power and strong acceleration, and I'm pleased that its precise handling qualities are retained in supersonic...