Examining the flight of a Bell UH-1H that crashed into terrain near Raton, New Mexico.
CAUSE & CIRCUMSTANCE
There are many examples of experienced helicopter pilots flying into terrain. These cases often involve poor visibility and the pilot’s desire to complete his or her mission, whether it be mountain rescue, patient air ambulance or executive transport. When it happened near Raton, New Mexico, in 2018, the circumstances were familiar. The Bell UH-1H “Huey” helicopter struck the ground 11 nm east of Raton at cruise speed. The aircraft was in level flight and in dark night conditions. A first responder, who spoke to the pilot as he was being loaded into a rescue helicopter, quoted him as saying the accident was “all his fault” and that he flew into the terrain. The pilot died as a result of his injuries while en route to the hospital. The pilot’s admission provided the answer to the question of what happened, and that was summarized by the NTSB. They found that “the probable cause(s) of this accident to be: The pilot's failure to maintain adequate altitude above mountainous terrain during cruise flight in dark night conditions, which resulted in controlled flight into terrain.”
A sectional map of the Raton, New Mexico area that the pilot should have checked closely. Source: Airnav.com
This cause statement leaves open the bigger question of why it happened. We may not be able to say for sure, but supporting information in the accident report and further information about the interesting mix of people on board the helicopter point to some possible explanations. The accident took place on Jan. 17, 2018. On that afternoon, a Hawker 800 private jet landed at Raton Municipal Airport (KRTN). On board were the owner of a newly acquired ranch near Raton and his guests. The jet had departed from Houston, the permanent residence of the passengers. Waiting for them in Raton was the Huey helicopter, which was owned by Sapphire Aviation LLC. Sapphire was one of many companies owned by the new ranch owner. The Huey pilot was employed by Sapphire. The purpose of the helicopter flight was to transport the five passengers to the Emery Gap Ranch, an 11,644-acre cattle ranch located about 35 mi. northeast of Raton and about 9 mi. north of the tiny hamlet of Folsom, New Mexico. The passengers were planning to celebrate a birthday at the ranch and return to Houston two days later. After the passengers boarded the Huey, it lifted off at about 1750 Mountain Standard Time (MST) and proceeded in an east southeasterly direction. Although the skies were clear, night had fallen. Local civil twilight ended at 1735 and local moonset was at 1754. The one surviving passenger recalled seeing bright starlight, but in the absence of any ground lights or moonlight, the pilot would have been trying to see into what is commonly called a “black hole.” The elevation of Raton Airport is 6,349 ft. MSL. After less than 10 min. of flight, the helicopter crashed at an elevation of 6,932 ft. MSL, only 583 ft. above Raton. The surviving passenger, interviewed by an FAA inspector, said there was no turbulence during the flight and there were no warning lights in the cockpit. The pilot and copilot were calm before the passenger felt a “big bang” as they hit the ground. The helicopter rolled forward and came to a stop upside down. She found herself hanging in her seat by the seat belt and there was fuel pouring on her. She released her seat belt and left the aircraft. There were explosions and the helicopter was on fire. She called 911 and waited for emergency responders. Because of the remote location of the accident site, no rescuers arrived for about 2 hr. Paramedics arrived at 2015. There were five fatalities. The Investigation The NTSB investigator in charge was joined by FAA inspectors and representatives from Honeywell Aerospace, Rotorcraft Development Corp. and the Air Accident Investigation Board (AAIB) of the U.K. An aerial imagery specialist from the NTSB also traveled to the accident site. The wreckage was located on Blosser Mesa, about 2.5 m. southwest of Green Mountain. The terrain, which a casual observer might describe as flat, was actually a gradual upslope.
One of the two Bell UH-1H altimeters from the crash. Source: NTSB
There was a 474-ft. ground scar formed by the helicopter’s skids, followed by the signature of the rotor blade striking the ground. The main rotor was found 60 ft. beyond the rotor strike and the remains of the cabin were found 66 ft. beyond the main rotor. The cabin was destroyed by fire. The grasses in the rocky area around the wreckage burned as well. Investigators conducted a thorough examination of the wreckage. Cockpit instruments were charred and deformed, but two altimeters were found. Only the left-side instrument could be read, and it showed an altitude of 6,760 ft. The barometric pressure setting on the two instruments differed--one was 30.18 and the other was 30.28. The weather at Raton at the time of the accident was wind direction, 030 deg. at 10 kt.; 10 mi. visibility; temperature, 1C; and altimeter setting, 30.26. There was no moon visible. The front range of the Rocky Mountains meets the great plains at Raton. The area east of Raton is high table land punctuated by outcrops of volcanic rock and cinder cones. The plains are broken by eroded canyons that cut through sandstone layers. To fly directly from Raton to Emery Gap Ranch, you must cross a long finger of higher elevation land that runs southeast from 9,627-ft. Fishers Peak near Trinidad, Colorado, to Capulin Volcano National Monument in New Mexico, a cinder cone that rises to 8,182 ft. The sectional chart for the area shows numerous peaks above 8,000 ft. and a minimum safe sector altitude of 9,200 ft. Contour lines on the sectional chart show few, if any, elevations where the helicopter could have crossed at an altitude below 8,000 ft. The Victor airway that most closely approximates the direct route of flight, V-263, has a minimum en route altitude (MEA) of 11,600 ft. A ranch employee said the pilot most commonly flew there from Perry Stokes Airport near Trinidad and probably had not flown from Raton to the ranch before. The terrain between Trinidad and the ranch is depicted on the sectional chart as relatively flat, gradually sloping downhill to the east with typical elevations of about 6,500 ft. The accident report does not speculate as to why the pilot was headed east southeast rather than northeast directly toward the ranch. It seems he may have been planning to intercept U.S. Highway 87 and follow it to the town of Capulin before heading north toward Folsom and the ranch. The sectional chart shows the highway generally lies between 6,500 ft. and 7,000 ft. The elevation at Capulin is 6,844 ft. Taking this southerly route could have appealed to the pilot if he wanted to stay low and navigate by using ground references. The UH-1H helicopter, N658H, was originally manufactured in 1967 but was recertified in 2007 by Rotorcraft Development Corp. After being released by the General Services Administration in 1996, it was owned and operated by seven different operators before it was acquired by Sapphire Aviation on Feb. 10, 2017. It was certified as a restricted category external load aircraft, not for passenger-carrying operations. According to maintenance records, in 2016, when the helicopter had 4,334.2 total hours, it was extensively modified. Among the many modifications were new flight, navigation and engine instruments. These included Garmin G500H PFD/MFDs, air data computers (ADC) and attitude heading reference systems (AHARS) on both the pilot and copilot panels, and a Garmin GTN 750H and a GTN 650H GPS display. In addition, a Garmin GTX 345R transponder and a GRA 55 radar altimeter were installed. At the time of the accident, the helicopter had 4,420.5 hr. airframe total time. Pilots and Passengers The 57-year-old pilot was employed by Sapphire Aviation in September 2017, just four months before the accident. He had been a law enforcement pilot for the California Highway Patrol for 20 years, then a helicopter maintenance test pilot and a utility pilot until he was hired at Sapphire. He graduated from U.S. Army Warrant Officer Helicopter Flight School in 1984 and had served in the U.S. Army Reserve flying the UH-1. The pilot had a commercial helicopter certificate with an instrument rating and a night vision goggle (NVG) endorsement. His last annul FAR Part 135.293 and Part 135.299 annual flight checks were flown in a Bell 206 and MD 500 in September 2016. On his Sapphire employment application, he had meticulously listed his flight time on nine different helicopter types, including 2,065 hr. in the UH-1. He showed a total of 8,613 flight hours in turbine rotary-wing aircraft. The pilot had logged 56 hr. in the last 12 months, and 3 hr. in the last 90 days, all in the UH-1. His most-recent FAA medical exam, a Class II, was accomplished just a month before the accident. He needed to use corrective lenses while flying. He reported having had one accident, in 2007--a crosswind tailwheel airplane landing gone wrong. However, the rest of his record was spotless. According to an obituary in the Auburn (California) Journal, the pilot had been a chief warrant officer who flew missions in Central and South America, and he flew many rescue missions in extreme conditions. He was the 2005 winner of the Jeep Hero Award and donated his prize to a homeless organization. He was also in the Hall of Fame at the New Mexico Military Institute. A post-accident toxicology test showed that the pilot had a relatively low, but therapeutic, level of Benadryl (diphenhydramine) in his blood. Benadryl is one of the over-the-counter drugs the FAA restricts because it induces drowsiness. Seated in the left seat of the helicopter was a pilot-rated passenger, the head of Sapphire. He was 67 years old and also had been through army warrant officer flight school. He flew Cobra gunships in Vietnam, then spent 33 years with the Pasadena, Texas, police department, rising to the rank of chief of police. After retiring from his police job, he spent 13 years as a system and operations manager at a Texas university. Sapphire hired the pilot-passenger in January 2017 and he listed experience in 10 different helicopter types on his employment application. He had a commercial rotorcraft certificate and a Class II medical certificate specifying he must wear corrective lenses. His total flight time was 3,140 hr. He had only flown 20 hr. in the 12 months before he began work at Sapphire. His flight time in the year prior to the accident was unknown. Apparently the two pilots performed a variety of tasks for Sapphire’s owner. Both were listed as working at a shooting center in the Houston area, but the accident pilot lived in Trinidad, Colorado, and performed maintenance duties. He serviced the helicopter, but he also serviced and repaired vehicles. A charge card invoice showed he installed a GPS and cellphone booster on a Hummer vehicle. Besides the pilots in the two front seats, there were four passengers aboard the flight. One couple were long-time residents of Zimbabwe, where the man had been a prominent political opponent of the Mugabe regime. The other two passengers were the owner of the ranch and his girlfriend, who was also the daughter of the pilot-passenger. The owner of the ranch was Charles Ryland Burnett III. He was also the owner of Sapphire Aviation, the operator of both the Hawker 800 and the UH-1. He had owned the jet since 2013, but purchased the ranch and helicopter in February 2017. Thinking About Possible Causal Factors I see two areas of analysis to this case, one objective and the other interpersonal. The pilot was highly experienced flying Hueys and other helicopters in all kinds of hazardous conditions, but he was new to the operation. He had taken Benadryl, a common sedating sleep aid, sometime in the two days before the accident, and the level in his bloodstream was enough to affect his alertness. He was familiar with the general area, but not the terrain from Raton to the ranch. Flying toward an upslope creates the illusion of being on a steeper than actual flight path. The “black hole” effect removes visual cues. Experienced pilots fly lower than inexperienced pilots in night visual conditions, according to a 2008 study. All of these factors could have contributed to the accident. The fact that the two altimeters found in the wreckage differed in their altimeter setting and differed from the Raton-reported setting indicates the two pilots did not communicate systematically. The pilot-passenger had just arrived from Houston and was probably not involved in preflight planning. They probably did not run a before-takeoff checklist. The fact that the pilot headed southeast and climbed only a few hundred feet after takeoff indicated he had not carefully examined a sectional or terrain chart and that he intended to navigate by reference to the ground and avoid obstacles by visual means. The pilot was trained to use night vision goggles but did not use them on the flight. The helicopter was equipped with expensive, late-model avionics that would have supported clear graphic terrain representations and terrain warnings, but the pilots apparently paid them no heed. In the 56 hr. the pilot had flown the Huey since it was purchased, he may not have become very familiar with the avionics. His last flight check was in 2016. There was no record of him receiving formal training in the use of the avionics. This is another indication that he reverted to his customary method of night flying--visual contact. All of these objective factors point to poor planning and overconfidence on the pilot’s part. The interpersonal factors are harder to establish. Investigators provided a hint when they classified the flight as a “personal” Part 91 flight. Normally, a professionally flown flight is classified as an executive/business flight. The ranch owner was described by people who knew him as both determined to get his way and as sweet and kind, and never having overridden any expert advice in 30 years. The pilots and passengers were friendly and looking forward to celebrating a birthday. The owner had acquired the helicopter and the ranch, and employed the pilot, at about the same time. His goal of using them all was obvious. When the pilot took off into dark night conditions under visual flight rules, he must have known this was a hazardous course of action. He likely did not want to disappoint the passengers. Even if the owner did not express any direct desire to fly that flight, there could have been an unspoken commitment to go. The interpersonal factors could suggest that the pilot was reluctant to cancel the flight when his judgment probably told him he should. As new private fliers move into aircraft charter and ownership, they should be aware of the influence they have on their crews. Crews take cues from the client. Former police and military pilots are especially mission oriented. Establishing some firm ground rules about no-go conditions is important. It’s wise to get some expert outside help doing that and to put it in writing. Then meeting with the crew(s) and putting the rules into effect makes them clear.
—A former military, corporate and airline pilot, Roger Cox was also a senior investigator at the NTSB. He writes about aviation safety issues.
