What happened
On August 16, 2010, at approximately 1445 EDT, a Bell UH1H helicopter, identified by U.S. Customs tail number 21769 and no FAA registration number (UNREG), was involved in an accident during a training flight at Warrenton-Fauquier Airport (HWY) in Warrenton, Virginia. The flight, which originated from Manassas, Virginia (HEF), was being conducted under visual flight rules for the purpose of public use training.
The pilot receiving instruction was performing a practice autorotation from 1,800 feet to runway 33. During the touchdown phase, the pitch of the aircraft increased, causing the tail rotor and stinger to make contact with the runway. As the helicopter began to shudder, the flight instructor took control and pitched the aircraft forward to attempt to correct the tail-low condition. Both crew members worked to maintain control, but the helicopter lost tail rotor control and pivoted to the right. The aircraft ultimately struck the runway in a left-skid-low attitude and came to a stop near the taxiway exiting runway 33. The crew members were not injured.
The investigation
A preliminary examination of the wreckage showed that the tail rotor had separated from the aircraft and the vertical stabilizer had been severed. The pilots reported that there were no mechanical anomalies present during the autorotation maneuver.