Bell 212 N212HP accident near Willow Creek, California

Probable cause

The rappeller's failure to properly latch the rappelling harness to the rappelling assembly before exiting the helicopter.

NTSB analysis

The purpose of the flight was to conduct proficiency rappel training. During a preflight equipment check, one of the rappellers identified a broken "Kong" clip on the Tri-link/J-hook interface on the harness. He replaced the Kong clip with a rubber O-ring (an authorized substitution) and then he returned to the helicopter. Minutes later, with the helicopter in a stabilized hover, witnesses on the ground reported that they observed the rappeller transition from inside the helicopter to the port side skid, then fall down the rope at excessive speed. Postaccident examination of the rope and harness assembly revealed that the rappeller's J-hook was attached to the Sky Genie and rope; however, the J-hook was not attached to the Tri-link and harness. A broken O-ring, believed to be the O-ring used to center the Tri-link and J-hook, was found on the ground approximately 30 feet from where the harness assembly was located. Evidence obtained during the investigation suggests that the rappeller's Tri-link and J-hook were not mechanically linked (prior to the rappeller transitioning to the skid), but rather inadvertently linked together with a non load-bearing O-ring used to center the latching devices. Examination of the J-hook, Sky Genie, Tri-link and harness by investigators from the US Forest Service revealed no evidence of malfunction or defect.

Text from the NTSB. Open the NTSB docket for WPR09TA356 for the full record.