The third X-43A hypersonic research aircraft and its modified Pegasus booster rocket leaves the runway, carried aloft by NASA's B-52B launch aircraft from the NASA Dryden Flight Research Center at Edwards Air Force Base, Calif., on Nov. 16, 2004. About an hour later, the Pegasus booster was launched from the B-52 to accelerate the X-43A to its intended speed of Mach 10.