On February 23rd, 2008, the Spirit of Kansas, 89-0127, crashed on the runway shortly after takeoff from Andersen Air Force Base in Guam. This was the first ever crash of a B-2 bomber and one of the most costly aviation accidents ever (total loss was estimated at US$1.4 billion).
The good news is, the two officer crewmen survived after safely ejecting from the plane before it crashed. Also, there were no munitions on board.
An investigation into the accident found out that heavy rains caused water to enter the plane's skin-flush air-data sensors, which distorted the angle of attack and yaw data the sensors were feeding the computerized flight-control system. As a result, the flight-control system, using false data, made the disastrous correction during the B-2 takeoff.
Following the crash, a B-2 that was already flying was called down and the 19 other bombers were grounded until the initial investigation was complete.
Because the B-2 were grounded, 6 B-52s of the 96th Bomb Squadron, 2nd Bomb Wing at Barksdale Air Force Base, Louisiana were deployed.