Palmer, AK, USA
N351SH
Airbus Helicopters AS350-B3
A local lodge had contracted with the helicopter operator to transport passengers from a private residence to a heli-ski area at a nearby mountain. The surviving passenger stated that, before the last ski run of the day, the pilot attempted to land on a ridgeline but that the helicopter lifted off for an attempted second landing. The passenger also stated that, during the second landing attempt, the snow was “real light” but that the helicopter became “engulfed in a fog which made it appear like a little white room.” The helicopter subsequently began “going backward real fast” and impacted the ridgeline and rolled backward down the mountain. Postaccident examination of the airframe and engine revealed no preimpact mechanical malfunctions or failures that would have precluded normal operation of the helicopter. The passenger’s recollection of the conditions just before the accident was consistent with whiteout conditions caused by rotor wash while the helicopter was hovering near the ridgeline. Thus, the pilot likely experienced whiteout conditions during the second landing attempt, which caused him to lose visual reference with the ridgeline and resulted in the helicopter impacting terrain. Title 14 Code of Federal Regulations Part 135 required flight-locating for the helicopter in case it was overdue so that information about the helicopter’s location could be reported to a Federal Aviation Administration (FAA) or a search and rescue facility. The helicopter operator stated that it had delegated the responsibility for flight-locating to the local lodge. However, this delegation was not documented in the company’s FAA operations specifications or general operations manual, as required by Part 135. On the day of the accident, the local lodge was providing flight-following for the accident helicopter, which, unlike flight-locating, was not required by Part 135. The helicopter was expected to depart the heli-ski area for the principal operations base once all the ski runs had been completed. The flight-follower informed his supervisor that 40 minutes had elapsed since the helicopter moved from its last recorded position and that there had been “no positive comms” with the ski guide during the last 1.5 hours; this notification was made 41 minutes after the last “ping” from the helicopter. However, the remote area in which the accident flight was operating had limited communication capabilities, and no clear evidence indicated that an accident had occurred. The flight-follower’s supervisor contacted another heli-ski company to help determine the status of the helicopter. The heli-ski company considered the flight to be “ops normal” and expected that the last lift would occur shortly. The supervisor instructed the flight-follower to “keep an eye on” the accident helicopter; however, the lodge’s emergency response plan stated that a search and rescue facility should be contacted “if communication with the helicopter is not established by the end of the prearranged [time] or 30-minute grace period.” Therefore, it would have been reasonable for the lodge to activate its emergency response plan at this point given that the helicopter’s location was unknown at the time. The flight-follower continued to try to reach the helicopter but was unsuccessful. About 90 minutes after the last flight-following “ping” for the helicopter, the lodge received erroneous information from the heli-ski operator that the accident helicopter was “inbound” for the private residence; however, lodge personnel did not realize that this information was not accurate and that the accident had occurred immediately after the last ping. This incorrect information likely played a role in the lodge’s further delay in activating its emergency response plan. About 1 hour and 50 minutes after the accident (and the last flight-following ping), the heli-ski operator notified the accident helicopter operator about the overdue aircraft. Five minutes later, the lodge notified the helicopter operator that it was activating its emergency response plan. About 2 hours after the accident occurred, the helicopter operator activated its emergency response plan. About 17 minutes later, the helicopter operator notified the Alaska Rescue Coordination Center. The director of operations for the helicopter operator stated that the search and rescue notification did not occur before that time because he had been “working through the information that was provided” about the helicopter. The helicopter wreckage was located about 3.5 hours after the accident. Rescue personnel launched within 1 hour of notification and arrived on scene less than 30 minutes later (about 5 hours 40 minutes after the accident). The surviving passenger was transported via helicopter to a local hospital. Upon arrival at the hospital, the surviving passenger had hypothermia and severe frostbite. A shorter exposure to the cold would likely have decreased the severity of the surviving passenger’s injuries. However, a faster emergency response time (and thus shorter exposure to the cold) could only have occurred if the notification to search and rescue personnel had been timelier. Thus, because the lodge and the helicopter operator did not activate their emergency response plans sooner, the initiation of search and rescue operations was delayed. Given the circumstances of this accident, the investigation considered three types of training that the pilot should have received: inadvertent instrument meteorological conditions (IIMC) training; controlled flight into terrain-avoidance (CFIT-A) training, during which instruction in whiteout conditions would be conducted; and ridgeline training. Review of the operator’s pilot training program showed that ridgeline training was not provided for the make and model of the accident helicopter (or the previous helicopter in which the accident pilot had been trained). Further, IIMC training was a part of CFIT-A training, and the CFIT-A manual stated that pilots were required to complete IIMC training annually. However, the chief pilot for the helicopter operator stated that the related test for pilots (to demonstrate understanding of the subject) was only administered when a pilot was first hired, and the director of operations stated that the company’s only IIMC flight training involved recovery from unusual attitudes. In addition, review of the accident pilot’s flight training records found that he completed IIMC training 14 months before the accident (which was about 1 year after he began working for the operator), but the records did not reflect the specific IIMC training that the pilot received. Based upon the information provided by the operator, it could not be determined if the accident pilot had fulfilled the training requirement. The director of operations reported that the helicopter operator did not accomplish flight training as part of its CFIT-A training; however, flight training was not required for that subject, and the pilot received CFIT-A ground training. The CFIT-A manual stated that, if inadvertent whiteout conditions were encountered, the pilot was to rely on flight instruments and carefully attempt to maneuver the helicopter away from obstacles and terrain. Additional review of training records revealed that, during competency checks, the helicopter operator was not evaluating several requirements of 14 CFR 135.293, including recovery from IIMC, navigation, air traffic control communication, and instrument approach flying. Paragraph (c) of the regulation required a pilot to demonstrate the ability to maneuver the helicopter into visual meteorological conditions after a simulated encounter with IIMC, a skill that was needed during the accident flight. The operator stated that it did not have any instrument-flight-rules (IFR) aircraft capable of IFR approaches, but the GPS model installed on the accident helicopter had IFR capabilities with instrument approach procedures in its database. Thus, given the deficiencies in the operator’s pilot training program and Part 135 checkrides, particularly regarding IIMC, it is likely that the pilot did not meet the qualification standards to be the pilot in-command of the accident flight. The FAA principal operations inspector (POI) for the operator failed to ensure that the company’s operations specifications (specifically, paragraph A008) contained the operational control information required by 14 CFR 119.7 and 135.77. (Flight-locating was part of operational control.) The company’s operations specifications did not describe who would be responsible for the safe operation of company flights and how those flights would be operated to meet requirements; thus, the operations specifications were incomplete. Although the company should have noticed this omission before the operational specifications were signed, the POI was ultimately responsible for ensuring that the operations specifications contained all the required information. FAA Order 8900.1, paragraph 3-1255, discusses helicopter flight training maneuvers that “must be conducted for satisfactory completion of each category of flight training.” The order also stated that all helicopter pilots operating under Part 135 “must be trained on procedures for the avoidance and recovery from IIMC” and that inspectors were required to ensure that operational procedures for recovery from IIMC are incorporated into the certificate holder’s training curriculums. Thus, the POI failed to ensure that the operator’s training program contained all required elements, which also included ridgeline training, before approving the training program. In addition, the POI was also unaware that the operator was not conducting competency checks in accordance with section 135.293(c) and that its checkrides were only assessing a pilot’s recovery from unusual attitudes. From 2011 to 2013, the POI was the chief pilot for the accident operator; from 2001 to 2011, she worked at another helicopter company with the person who later became the president of the accident operator. The POI started her employment with the FAA in 2016 and, 2 years later, became the POI for the accident operator. The available evidence for this investigation was insufficient to determine whether the POI’s previous employment history was a factor in the inadequate oversight of the accident operator. Toxicology testing of specimens from the senior lead ski guide identified two central nervous system stimulant drugs: amphetamine and cocaine. Given the drug levels measured in his blood, the senior lead ski guide was likely impaired by drug effects at the time of the accident. Toxicology testing of specimens from the other lead ski guide identified delta-9-tetrahydrocannabinol (THC), the primary psychoactive component in cannabis. The low THC level measured in his blood indicates that he was not likely experiencing significant impairment from THC effects at the time of the accident. Although ski guides are not considered crewmembers according to the Federal Aviation Regulations, they have safety-related responsibilities during heli-ski flights such as coordinating with pilots about landing and pickup zones and assisting pilots with hazard and pickup zone identification. However, the investigation was unable to determine whether the senior lead guide’s illicit drug use played a role in the accident.
HISTORY OF FLIGHTOn March 27, 2021, about 1836 Alaska daylight time, an Airbus Helicopters AS350-B3, N351SH, was substantially damaged when it was involved in an accident near Palmer, Alaska. The pilot and four passengers were fatally injured, and one passenger was seriously injured. The helicopter was operated under Title 14 Code of Federal Regulations (CFR) Part 135 as an on-demand air charter flight. Representatives from the operator, Soloy Helicopters, reported that the helicopter was under contract to Tordrillo Mountain Lodge (TML) to transport passengers from a private residence on Wasilla Lake, Wasilla, Alaska, to the Chugach Mountains to conduct heli-ski operations. (The Organizational and Management section of this report provides additional information about Soloy Helicopters and TML.) According to Heli Ski US (HSUS), which is a trade association that promotes helicopter skiing safety and provides support, heli-ski operations involve a “helicopter [that] is utilized to provide up-hill transportation for participants” of “guided winter recreation activities including, but not limited to skiing.” GPS data showed that the helicopter arrived at the Wasilla Lake residence about 1450. About 53 minutes later, the helicopter departed the residence and flew toward the Chugach Mountains. The surviving passenger recalled “nice” but “kind of creepy weather” in the mountains, which delayed the departure for the ski trip. The helicopter arrived at the intended operating area about 19 minutes later and subsequently flew multiple runs between about 1612 and 1807. GPS data showed that the helicopter departed for the last run of the day at 1827:05 on a northwest heading and climbed to about 5,900 ft mean sea level (msl). The helicopter's final movements began about 1833 over a ridgeline at an altitude of 6,266 ft msl (about 14 ft above ground level) and at a groundspeed of 1 knot. The helicopter maintained its low altitude and groundspeed as it maneuvered over the ridgeline. The data track ceased at 1836:42 near the location of the accident site, which is shown in figure 1. Figure 1. Location of departure point, previous operating areas, and the accident site. The surviving passenger stated that the passengers had completed five or six runs and that the accident occurred while the helicopter was relocating for the last run of the day. The surviving passenger also stated that the pilot first attempted to land the helicopter normally on the ridgeline but that the helicopter subsequently “went up to try to get into the right position.” The surviving passenger further stated that the snow was “real light” and that, while the pilot was attempting to land a second time, the helicopter was “engulfed in a fog, which made it appear like a little white room.” The passenger recalled that another passenger yelled “don’t do it” three times just before the helicopter “began going backward real fast and impacted the rocky mountainside several times.” PERSONNEL INFORMATIONA review of the pilot’s training records indicated that he completed recurrent training on January 21, 2021, including a pilot competency check and a line check, as required by 14 CFR 135.293 and 135.299, respectively. In addition, the pilot completed CFIT-A ground training in January 2021 and IIMC flight training in January 2020. Records showed that the IIMC flight training lasted 1 hour and covered “T/R [tail rotor] failures, autorotations, emergency ops.” The records did not indicate the specific IIMC training that the pilot received, and no other record was found showing IIMC flight training for the pilot. The IIMC flight training also included pinnacle landings and slopes and heli-ski and snow operations. AIRCRAFT INFORMATIONThe accident helicopter was equipped with a Garmin Aera 660 GPS, which was certified for visual flight rules (VFR) flight but had the capability to display IFR procedures and maps. The helicopter was also equipped with a Kannad 406-MHz AF Compact emergency locator transmitter (ELT) that was installed on the upper right side of the right baggage compartment. METEOROLOGICAL INFORMATIONAt 1600, the Anchorage, Alaska, upper air sounding wind profile indicated light surface wind from the north above the surface with little directional variation with height and increasing wind speed. At an altitude of about 6,000 ft, the wind was from 350° at 21 knots with a temperature of -17°C. The sounding was characterized as conditionally unstable below 6,000 ft and stable above that level. The Universal Rawinsonde Observation analysis program sounding supported light turbulence below 8,000 ft and mountain wave activity. The northerly wind south of the ridgeline (the accident location) would have resulted in a general downslope wind flow near the accident site. A pilot operating on Knik Glacier (near the accident site) a few hours before the accident reported light surface wind with stronger wind at altitude. This pilot indicated that it “was windy as heck at altitude but dead calm on the valley floor.” A snowmobile tour operator at Knik Glacier reported that, during the morning and afternoon tours on the day of the accident, he noticed large plumes of snow blowing off the nearby mountain peaks, and he estimated the wind to be between 30 to 40 miles per hour from the west. AIRPORT INFORMATIONThe accident helicopter was equipped with a Garmin Aera 660 GPS, which was certified for visual flight rules (VFR) flight but had the capability to display IFR procedures and maps. The helicopter was also equipped with a Kannad 406-MHz AF Compact emergency locator transmitter (ELT) that was installed on the upper right side of the right baggage compartment. WRECKAGE AND IMPACT INFORMATIONAerial assessment of the accident site on the day after the accident revealed that the helicopter impacted terrain about 15 to 20 ft below the top of the ridgeline. The main wreckage came to rest on its right side about 500 ft downslope from the initial impact area, as shown in figure 2. The debris field extended about 900 ft downslope from the top of the ridgeline. Figure 2. Accident site (Source: Alaska State Troopers). Postaccident examination of the airframe and engine revealed no preimpact mechanical malfunctions or failures that would have precluded normal operation of the helicopter. The ELT’s installed location (the upper right side of the right baggage compartment) was found packed with snow. The ELT remained secured to its airframe mount via a velcro strap. The ELT’s antenna coaxial cable and remote cockpit control wiring remained connected. The ELT switch was found in the ARM position. The external antenna had been fractured from its mount and was not located. Postaccident testing of the ELT found that it was working properly and that the ELT had transmitted during and after the accident sequence for 178 hours (12,884 bursts at 50-second intervals). ADDITIONAL INFORMATIONHeli-Ski Guides Two passengers aboard the accident flight were heli-ski guides who TML contracted for the accident flight. Guides provide a critical safety role during a flight, and their responsibilities can include loading and unloading passengers, understanding surface snow conditions, and coordinating with pilots about landing and pickup zones. The HSUS operating guidelines specify duties for guides during the approach and landing, which include assisting the pilot with hazard and pickup zone identification, confirming clearances to terrain features on short final, and ensuring passenger safety after landing. TML offered annual training to heli-ski guides working at its operation each season, which the accident guides attended in January 2021. TML was listed on the HSUS website as a member at the time of the accident. HSUS designated the accident guides as lead guides. According to HSUS, a lead guide is “an individual designated by an Outfitter to supervise the activities of one or more Groups and who meets the recommended qualifications for that position as established in the Guide Qualification Guidelines.” One of the accident guides was designated as the senior lead guide for the flight. Flight-Locating Information Soloy Helicopters had delegated flight-locating responsibilities to TML. The NTSB requested that the FAA provide a definition or clarification for the term “flight locating” given that the Federal Aviation Regulations did not define that term. The FAA acknowledged that “flight locating” is not defined but stated that 14 CFR 135.79, Flight Locating Requirements, stated that procedures were required to be established for locating each flight for which an FAA flight plan is not filed. The regulation specified the following procedures: 1. Provide the certificate holder with at least the information required to be included in a VFR flight plan. 2. Provide for timely notification of an FAA facility or search and rescue facility, if an aircraft is overdue or missing. 3. Provide the certificate holder with the location, date, and estimated time for reestablishing communications, if the flight will operate in an area where communications cannot be maintained. The regulation also required that flight-locating information be retained at the certificate holder's principal place of business, or at another place designated by the certificate holder in its flight-locating procedures, until the completion of each flight. Flight-following was not defined for Part 135 operations and was not required for aircraft operating under Part 135. The term “flight follower” generally refers to personnel who perform various flight support duties. MEDICAL AND PATHOLOGICAL INFORMATIONPilot The State of Alaska Medical Examiner’s Office in Anchorage performed an autopsy of the pilot. His cause of death was multiple blunt force injuries. Toxicology testing performed by the FAA’s Forensic Sciences Laboratory detected no tested for substances. Ski Guides According to the autopsy inspection report (which comprised an external examination only) issued by the State of Alaska Medical Examiner’s Office, the senior lead guide’s cause of death was blunt force head injury. Toxicology tests performed by NMS Labs identified the following in the senior lead guide’s blood specimen: amphetamine at 96 ng/ml, cocaine at 52 ng/ml, and the inactive cocaine metabolite benzoylecgonine at 1,000 ng/ml. The autopsy inspection report for the other lead guide showed that his cause of death was multiple blunt force injuries. Toxicology tests of the lead guide’s blood specimen performed by NMS Labs identified delta 9-tetrahydrocannabinol (THC), the primary psychoactive component in cannabis, at 1.1 ng/ml. Amphetamine is a central nervous system stimulant drug that is available by prescription for the treatment of attention deficit disorder and narcolepsy. It carries a boxed warning about its potential for abuse and has warnings about an increased risk of sudden death and the potential for mental health and behavioral changes. In some preparations, a prescription drug is metabolized to amphetamine; commonly marketed names include Adderall, Dexedrine, and Vyvanse. Amphetamine may also be produced and used illicitly. Cocaine is another central nervous system stimulant drug. Initial effects of cocaine use include euphoria, excitation, general arousal, dizziness, increased focus, and alertness. At higher doses, effects can include psychosis, confusion, delusions, hallucinations, fear, antisocial behavior, and aggressiveness. Late effects, beginning within 1 to 2 hours after use, include depression, agitation, nervousness, drug craving, fatigue, and insomnia. Additional performance effects would be expected after higher doses, with chronic ingestion, and during drug withdrawal, including agitation, anxiety, distress, inability to focus on divided-attention tasks, inability to follow directions, confusion, hostility, time distortion, and poor balance and coordination. THC's mood-altering effects include euphoria and relaxation. Also, THC can cause alterations in motor behavior, perception, cognition, memory, learning, endocrine function, food intake, and body temperature regulation. Specific performance effects may include a decreased ability to concentrate and maintain attention. In addition, impairment in retention time and tracking, subjective sleepiness, distortion of time and distance, vigilance, and loss of coordination in divided-attention tasks have been reported. Significant performance impairments are usually observed for at least 1 to 2 hours after marijuana use, and residual effects can occur for up to 24 hours. THC may be detected at low levels in the blood for days or weeks after use. SURVIVAL ASPECTSThe helicopter was configured with the pilot’s seat in the front right seat position. Passenger seats were located in the front left seat position and a bench in the cabin with four seating positions. Figure 3 shows the helicopter seating configuration. The senior lead guide was in the left front seat; the other lead guide was in aft seat No. 1. The deceased passengers were in aft seat Nos. 2 and 4; the surviving passenger was in aft seat No. 3. Figure 3. Simplified drawing of the accident helicopter showing seating positions with rear bench seat position numbers annotated. Surviving Passenger Account According to the surviving passenger, when the helicopter came to rest, he was still inside the helicopter with his body stuck in snow and lodged between two other occupants. He observed one of the other passengers (later identified as the occupant in aft seat No. 4) sitting in the snow outside the helicopter and heard thumping sounds from the bottom of the helicopter. The surviving passenger and the passenger who had been in aft seat No. 4 verbally communicated with each other using short messages. The surviving passenger noted that the passenger then began to move downslope in a seated position (the surviving passenger was unsure what that passenger was doing) and that he (the passenger who had been in aft seat No. 4) eventually stopped responding. The surviving passenger recalled that he eventually saw the light of a helicopter, which appeared to have left the area before coming back and hovering over the accident site. The passenger did not recall anything else until he woke up in a hospital. Upon arrival at the hospital, the passenger had a recorded internal temperature of 82°F along with extensive frostbite damage to both hands. Flight-Following and Search and Rescue Efforts A TML heli-ski guide (who was not aboard the accident helicopter) reported, during a postaccident interview, that he was “on radio communications and flight following” for the lodge on the day of the accident, and the TML radio/event log for that day showed that the flight-follower was in communication with a guide aboard the accident helicopter during the flight. The flight-follower stated that his “main source of communication” with the helicopter would be “via inReach, which is a Garmin satellite device.” The flight-follower also reported that the ski guide “was checking in every hour via inReach with a written message” and that inReach had an automated tracking system that sent a “ping” that the flight-follower tracked on his computer. The flight-follower further reported that he also used a flight-following website that depicted where the helicopter was operating. The TML flight-follower’s last communication with the ski guide (acknowledging that an inReach interval was received) occurred about 1824. About 10 minutes later, the last flight-following ping from the helicopter was received. About 1915, TML’s flight-follower notified a TML supervisor that there had been “no positive comms” with the ski guide within the last 1.5 hours and that “flight following indicates no movement” of the helicopter in the last 40 minutes. The supervisor contacted another heli-ski operator in the area, Third Edge Heli, to find out the status of the accident helicopter (Third Edge Heli’s operation base was closer to the helicopter’s last known location than TML’s operations base). During a conversation between repr
The pilot’s failure to adequately respond to an encounter with whiteout conditions, which resulted in the helicopter’s collision with terrain. Contributing to the accident was the (1) operator’s inadequate pilot training program and pilot competency checks, which failed to evaluate pilot skill during an encounter with inadvertent instrument meteorological conditions, and (2) the Federal Aviation Administration principal operations inspector’s insufficient oversight of the operator, including their approval of the operator’s pilot training program without ensuring that it met requirements. Contributing to the severity of the surviving passenger’s injuries was the delayed notification of search and rescue organizations.
Source: NTSB Aviation Accident Database
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