HICKAM AIR FORCE BASE, Hawaii – The Air Force on Thursday said the first crash of a B-2 stealth bomber was caused by moisture in sensors and estimated the loss of the aircraft at $1.4 billion.
The crash probably could have been avoided if knowledge of a technique to evaporate the moisture had been disseminated throughout the B-2 program, said Maj. Gen. Floyd L. Carpenter, who headed an accident investigation board.
The “Spirit of Kansas” abruptly pitched up, rolled and yawed to the left Feb. 23 before plunging to the ground at Andersen Air Force Base on the island of Guam. Both pilots ejected safely just after the left wing made contact with the ground in the first crash since the maiden B-2 flights nearly 20 years ago.
“It was just by the grace of God that they were safe, and the good (ejection) system,” Carpenter said.
Water distorted preflight readings in three of the plane’s 24 sensors, making the aircraft’s control computer force the B-2 to pitch up on takeoff, resulting in a stall and subsequent crash.
Carpenter said the pilots and crew followed procedures and “the aircraft actually performed as it was designed. In other words, all the systems were functioning normally.”
However, a technique learned by some two years ago that had gone widely unknown and unadopted probably would have prevented the crash, Carpenter said. The technique essentially heats the sensors and evaporates any moisture before data calibrations.
“This technique was never formalized in a technical order change or captured in ‘lessons learned’ reports. Hence, only some pilots and some maintenance technicians knew of the suggestion,” according to Carpenter’s executive summary of the accident.