Accident Details
On November 8, 2014, about 1000 central standard time, a Composite FX Mosquito XET helicopter, registration N922RM, impacted trees during approach for landing at Bailes Airport (7R9), Angleton, Texas. The pilot sustained minor injuries and the helicopter was substantially damaged. The helicopter was registered to and operated by the pilot under 14 Code of Federal Regulations Part 91 as a personal flight. Day visual meteorological conditions prevailed, and the local flight departed without a flight plan.
Pilot Account
According to the pilot, while in a crosswind turn at about 300 feet above ground level, the helicopter abruptly shuddered. The pilot lowered the collective control, entered an autorotation, and turned back toward the airport. As he approached the runway area, the helicopter skids passed over a row of trees by about 5 to 10 feet. Immediately after the skids cleared these trees, the pilot began a cyclic flare, which resulted in the tail rotor striking a tree. The helicopter then began to spin violently and impacted the ground several times, damaging the main rotor and tail boom.
Examination Findings
The helicopter was examined by Federal Aviation Administration and Composite FX personnel at the kit manufacturer's facility. The belt for the secondary drive reduction unit was observed to be loose, which allowed the teeth of the drive belt to "jump" the drive cogs on the pulley. The loose belt was due to excessive wear on the pulley. The operating manual pre-flight inspection includes a check for tension of this belt, during which the operator should attempt to deflect the belt by about 3/16 of an inch, with an estimated five pounds of finger pressure in the middle of a long, unsupported span of the belt.
Registration and Operator
The helicopter, N922RM, was registered to and operated by the pilot at the time of the incident.