A NASA mishap investigation board has concluded that an accumulation of ice in or on the unheated pilot-static system was the root cause of the crash of the X-31 experimental aircraft at Edwards AFB, California, on 19 January. The NASA board says that the build-up of ice blocked the small tube in the pilot static-pressure system which provided air-peed data to instruments in the cockpit, the aircraft's flight control computers and to the mission control centre at NASA's Dryden. centre.
Source: Flight International
