AIR MEDICAL SERVICES LLC: http://registry.faa.gov/N73AW
NTSB Identification: GAA16CA179
14 CFR Part 133: Rotorcraft Ext. Load
Accident occurred Wednesday, April 06, 2016 in Supai, AZ
Probable Cause Approval Date: 06/01/2016
Aircraft: BELL 206, registration: N73AW
Injuries: 1 Minor.
NTSB investigators used data provided by various entities, including, but not limited to, the Federal Aviation Administration and/or the operator and did not travel in support of this investigation to prepare this aircraft accident report.
The pilot reported that he was performing external load long line hauling operations with a helicopter and was on a return leg with two empty nets. During the approach to a hilltop helipad, the pilot reported that he performed a normal approach, rather than a long line approach. Subsequently, the 100 foot long line snagged on a ridgeline and the helicopter jerked in an uncontrollable turn to the right, touched down right skid first, and rolled over. The pilot reported that he forgot that the long line was still attached.
The tail boom was substantially damaged.
The pilot did not report any mechanical malfunctions or failures with the helicopter that would have precluded normal operation.
The operator submitted two operator/ owner safety recommendations to the National Transportation Safety Board investigator-in-charge. First, the operator revised the normal operation checklist. The revised checklist included a new "CARGO HOOK – CHECK" in both the BEFORE TAKEOFF and DESCENT AND LANDING checklist. Second, the chief pilot provided a copy of a memorandum to all employees that directs the use of an observer, when available, to observe the takeoff and landings and communicate any unsafe condition to the pilot via radio communication or hand signals.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot's decision to fly a normal approach and forgetting that the long line remained attached to the helicopter, which resulted in the line snagging on a ridgeline, a loss of lateral control, and a rollover.