On Friday, Virgin Galactic’s SpaceShipTwo successfully completed its third glide flight test over California’s Mojave Desert. The company’s SpaceShipTwo craft, called VSS Unity, was carried up to about 50,000 feet by VMS Eve, a WhiteKnightTwo craft, for a mid-air launch. The WhiteKnightTwo, a dual-fuselage, four-engine aircraft, was built specifically to launch Virgin’s sma...