Probable cause report issued on fatal STAR Flight fall

The US National Transportation Safety Board (NTSB) issued a report on 14 March identifying the probable cause of an accident that saw STAR Flight nurse Kristin McLain fall to her death as she and a patient were being hoisted into a helicopter on 27 April 2015.

Summarising what occurred that night, the NTSB states: “A helicopter with a pilot, a hoist operator, and a helicopter rescue specialist (rescuer) onboard was dispatched to transport an injured person out of an area of rough terrain. Based on the patient’s location and the time of the call, a night hoist operation was planned. The helicopter arrived on scene, and the hoist operator lowered the rescuer and equipment from the helicopter. While the rescuer and ground personnel prepared the patient for transport, the pilot and hoist operator looked for a nearby landing zone. Upon hearing radio calls from the rescuer that the patient was ready, the helicopter returned to the patient’s location, and the hoist operator lowered the hoist hook. The patient, who was in a Bauman bag, and the rescuer were then lifted from the ground by the hoist. The hoist operator continued to reel in the patient and the rescuer as the helicopter transitioned from a hover to forward flight. When the patient and rescuer were about 10 ft below the helicopter's skids, the rescuer fell about 100 ft to the ground.”

The report adds that the ground personnel who helped McLain to prepare the patient for transport said they did see anything unusual.

Although McLain and the patient made light contact with tree branches during the initial part of the lift, the NTSB states: “Examination of the rescuer's equipment did not reveal any failures or malfunctions that would explain the fall. Additionally, examination of the hoist hook and helicopter equipment did not reveal any abnormities. Also, review of video from a camera located on the hoist did not identify any failures in the equipment nor did it show how the rescuer was initially hooked into the hoist.”

Ending the report, the NTSB concludes: “In the absence of any equipment failure, it is likely that the rescuer was not properly fastened to the hoist.”