According to a preliminary NTSB report, the Bell 407 that crashed August 1 in Charleston, South Carolina, was missing one of two bolts that secure the lever assemblies in the tail rotor control system. The other bolt was in place but loose with the cotter pin for its attachment nut missing. The NTSB found that the bolts had been removed and reinstalled during maintenance performed on June 28, with the helicopter subsequently accumulating 15 flight hours.
N31PB was being operated by the Charleston County Sheriff’s Office when it crashed at 3:30 p.m. local time while attempting to land at Charleston AFB International Airport (KCHS) after a repositioning flight from Sumter Airport (KSMS) in South Carolina. The pilot reported that 35 minutes into the flight the helicopter started to slowly yaw right and that applying pressure on the left pedal produced no response. He stated, “It felt as if the pedals were not attached.”
The pilot then declared an emergency and set up a straight-in approach to Runway 15. At approximately 20 feet agl over the runway threshold, the helicopter continued to yaw right and the pilot’s attempt to arrest it and maintain level altitude by lowering the collective and reducing the throttle were unsuccessful. The helicopter hit the ground next to the runway after descending at a rapid rate, the tailboom severed, and the pilot sustained non-life-threatening injuries.