White Knight Testing X-37
mknewman writes "The innovative carrier plane used to air-launch SpaceShipOne has a new mission. At its inland spaceport in Mojave, Calif., the White Knight mothership has been involved in fit and high-speed taxi checks with a new passenger: the X-37, an unpiloted, reusable space plane. "
The White Knight will no doubt be significantly cheaper than a B52.
Just take a look at the two:
B52 - 8 big jet engines, combat crew of 5 (probably smaller for most NASA missions), 159 feet long.
White Knight - Not entirely familiar with the specs on this plane, but it looks like it has two engines, a crew of one or two, and is probably about 45 feet long or so (just guessing from photos and comparing it to length of X 37).
The White Knight is likely much cheaper to operate than a B-52, so that would probably explain it.