What happened
On March 27, 2021, an Airbus Helicopters AS350-B3, registration N351SH, was engaged in an on-demand air charter flight near Palmer, Alaska. The helicopter, operated by Soloy Helicopters LLC, was under contract with Tordriente Mountain Lodge to transport passengers for heli-ski operations.
After completing several runs, the helicopter departed for its final run of the day at approximately 1827 Alaska daylight time. While maneuvering over a ridgeline at an altitude of approximately 6,266 feet mean sea level, the aircraft encountered difficult conditions. A passenger reported that the pilot attempted a landing on the ridgeline, but the aircraft lifted off for a second attempt. During this second attempt, the helicopter became engulfed in fog, creating a whiteout effect. The aircraft subsequently moved backward rapidly and struck the rocky mountainside multiple times.
The accident resulted in 5 fatal injuries and 1 serious injury. One passenger survived the impact but suffered from hypothermia and severe frostbite due to the delay in rescue operations.
The investigation
Mechanical examination of the engine and airframe showed no preimpact failures that would have prevented normal operation. The investigation focused on the pilot's training and the operator's oversight.
Investigators found that the operator's pilot training program lacked specific modules for ridgeline operations and did not adequately address recovery from inadvertent instrument meteorological conditions (IIMC). While the pilot had completed IIMC ground training, the company's competency checks only assessed recovery from unusual attitudes rather than the full range of required maneuvers, such as navigation and instrument approaches.
Regarding the emergency response, the investigation noted that the lodge's flight-following procedures and the operator's delegation of flight-locating responsibilities were not properly documented in the company's operations specifications. A delay in activating the emergency response plan was attributed to erroneous information received from another heli-ski operator, which suggested the aircraft was inbound and operating normally.
Findings
- The pilot experienced whiteout conditions caused by rotor wash during a landing attempt, leading to a loss of visual reference.
- The operator's pilot training and competency checks were deficient, failing to evaluate necessary skills for IIMC encounters.
- The FAA principal operations inspector provided insufficient oversight by approving a training program that did not meet all regulatory requirements.
- The delay in notifying search and rescue organizations contributed to the severity of the survivor's injuries.
- Toxicology testing of the senior lead guide identified the presence of amphetamine and cocaine, though the investigation could not determine if drug use contributed to the accident.