The NB-52A 52-0003 and its sister ship, the NB-52B 52-0008 were diverted to the special mission of launching the X-15 hypersonic research airplane in 1958 following their service as early test examples of the B-52 Stratofortress. While the two Stratofortresses were engaged in the task of launching the three X-15 rocket planes, a series of rocket powered lifting bodies were developed that utilized the existing air launch capability. The NB-52A was a flying launch pad, which is a highly complex task. It had to supply the rocket planes that it carried with the propellants, gases, and power normally associated with a launch pad at the Kennedy Space Center, all while flying nine miles above the ground. This ability made the airplane an indispensable asset for aeronautical research. Its right wing was reinforced and equipped with a pylon to carry the heaviest wing-borne payloads ever dropped from an airplane. Some of the payloads that it dropped exceeded 50,000 pounds, nearly 15 of its own w