On December 10, 2007, one of the A160T prototypes crashed during a flight test at Boeing Advanced Systems' test facility in Victorville. A Boeing investigation determined the incident was caused when sensor data stopped being updated to the flight computer: with the feedback loop for the control system effectively cut, the helicopter "departed controlled flight and impacted the ground at a near-vertical angle." Much of the forensic evidence was burned in the post-crash fire. A number of potential areas that could have caused the software feedback update thread to stop were found, and those known problem areas were addressed and flight testing resumed on March 26, 2008.