History of Flight
On December 7, 2016, about 1015 mountain standard time, a Cub Crafters PA18-150 airplane, N444GB, was substantially damaged when it impacted terrain while maneuvering 15 miles southeast of Basin, Wyoming. The commercial-rated pilot was fatally injured, and the commercial pilot-rated crewmember was seriously injured. The airplane was registered to the Wyoming Wool Growers Association and operated by the United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS). Visual meteorological conditions prevailed and no Federal Aviation Administration (FAA) flight plan was filed for the flight. The animal damage management flight departed Worland Municipal Airport (WRL), Worland, Wyoming, about 0800.
According to the USDA APHIS Wildlife Services ground crew that worked with the flight, the airplane arrived in the area around 0820 for animal damage management. Ground crew members were positioned west, north, and east of the area where the airplane was operating. They had occasional visual contact with the airplane and radio communications with the pilot and crewmember, and could hear the engine operating until about 1000. One ground crew member reported hearing several passes consistent with a mitigation aspect of the flight just prior to 1000.
About 1015, the ground crew attempted to contact the pilot and/or crewmember via radio to change the area of focus but received no response. The ground crew tried multiple locations and means to make contact without success. At 1100, the agency search and rescue plan was activated, and about 1330 the airplane was located by aerial search and rescue teams.
A review of FAA air traffic control radar data did not reveal any primary or secondary radar targets consistent with the accident airplane. A handheld global positioning system (GPS) device was reportedly on board; however, a GPS was not found at the accident site. The airplane's exact route of flight after contact was lost could not be determined.
Months after the accident, the crewmember did not recall the specific events of the accident or accident flight.
Personnel Information
The pilot was based in Worland, Wyoming, and had started working for the USDA APHIS as a flight crewmember (gunner) in 2007. In March 2016, he began flying as a pilot for the program. He completed his initial flight training at the USDA flight training center in May 2016 in Cedar City, Utah, then moved to the field for a one-year training program. During this time, he flew with an instructor pilot and experienced flight crewmember—the same crewmember injured in the accident. The accident flight was still within the year training program.
The USDA flight training officer reported that the pilot was level-headed with good character and one of the best pilots to come through the program, with no concerns about his ability. Neither the State Director nor the ground crew expressed any concerns about the pilot.
The flight crewmember's medical certificate contained the limitation "must have available glasses for near vision." He was based in Worland, Wyoming, had been with the USDA APHIS for over 30 years, and a pilot for at least 20 years. He was qualified as both a pilot and flight crewmember and served as a flight instructor for the region. Neither the State Director nor the ground crew expressed any concerns about his abilities. He was serving as a flight instructor and flight crewmember during the accident flight and was the only instructor pilot who had flown with the accident pilot in the field.
Aircraft Information
The airplane was purchased by the Wyoming Wool Growers Association in September 2016 and underwent alterations for animal damage management, including installation of clear windshields, a skylight, "D" windows, and a right-side swing-up window. According to USDA personnel, the airplane was configured the same as the previous airplane flown by the pilot and flight crewmember.
The airplane was equipped with a stall warning indicator that sounded a horn in the cockpit when the airplane approached the critical angle of attack. It was not equipped with a visual angle of attack indicator.
Meteorological Information
Weather conditions recorded at Yellowstone Regional Airport (COD), Cody, Wyoming, located 38 miles northwest of the accident site at 0953 were: wind 350° at 8 knots, visibility 10 miles, sky condition 6,500 ft overcast, temperature -13°C, dewpoint -19°C, altimeter 30.35 inches of mercury. Conditions recorded at Worland Municipal Airport (WRL), 28 miles southeast of the accident site at 0953 were: wind 340° at 8 knots, visibility 10 miles, sky condition 6,000 ft overcast, temperature -13°C, dewpoint -18°C, altimeter 30.57 inches of mercury.
Wreckage and Impact Information
The wreckage was located in steep hilly terrain just below a ridgeline extending northeast to southwest, increasing in elevation to the south. The elevation at the accident site was about 4,400 ft mean sea level. The airplane came to rest in a ravine in a near-vertical, nose-down attitude, with the right wing uphill and left wing downhill. A strong smell of fuel was present.
The initial impact point was uphill and north-northwest from the main wreckage, with yellow paint chips, fragments from the green navigation light, vortex generators, and plexiglass found at the crest and down the north side of the hill.
Both wings exhibited accordion crushing along the leading edges and fabric tearing. The right wing had accordion crushing from the wing root outboard to the forward strut, with the right flap bent and wrinkled, and the right aileron bent down about 45° at the inboard portion. The right aileron cables were attached at the flight control and continuous through the pulley inboard to the fuselage; the forward cable was separated at the fuselage with broomstraw signatures consistent with overload. The right trailing strut was buckled about 8 inches outboard of the fuselage attach point. The right wing fuel tank was compromised. The pitot tube was clear of contamination.
The left wing had accordion crushing from the wing root to about midspan, with the left aileron bent, buckled, and wrinkled, and the left flap unremarkable. Left aileron cables were continuous from the aileron to the fuselage.
Landing gear: right main partially attached and bent aft; left main partially attached and bent slightly outward.
The fuselage from the baggage compartment aft to the empennage was unremarkable. Flight control cables and tubing were continuous and correctly rigged from the control stick aft to elevator and rudder. Rudder and trim cables on the left side were cut for extrication. The elevator trim measured 5 threads on top and 10 on bottom, consistent with 1° leading edge up from takeoff position, indicating slower airspeeds or aft center of gravity.
The fuselage remained attached to the empennage and both wings, including the cabin and instrument panel. The left side of the fuselage was crushed inward and to the right. The right window and door were broken; the forward windscreen fragmented; the left window and fuselage were impact damaged and cut for extrication. The instrument panel separated partially. The circuit breaker and switch panels provided no reliable readings.
The propeller separated at the flange and was partially buried directly beneath the wreckage. Both blades were bent and twisted, with chordwise scratches and leading-edge nicks. The spinner was crushed aft with rotational scoring.
Forward lap belt and two-point shoulder harness remained buckled; webbing was cut by first responders. Inertia reel functioned as designed. Rear lap belt and shoulder harness were not buckled; inertia reel functioned.
Instrument panel readings: airspeed indicator zero; attitude indicator inverted; vertical speed indicator 1,650 fpm down; Kollsman window 30.27; altimeter 9,000 ft; Hobbs meter 67.1. Digital tachometer did not provide current setting.
Engine controls: primer in and locked; mixture out 1/4 inch; carburetor heat out 1/2 inch. Forward and aft throttle controls were impact damaged and positions unreliable; aft throttle knob and lever not located. Fuel selector valve set at both.
The stall warning horn was removed and tested; no anomalies found.
The engine remained partially attached. The top spark plug and intake rod on No. 2 cylinder were impact damaged; exhaust tubing impact damaged; oil observed on dipstick. Valve covers and spark plugs removed for examination. Magneto P-leads were impact damaged and could not be functionally tested; magnetos produced spark when rotated. Engine continuity was confirmed on all cylinders. Spark plugs exhibited normal signatures. Fuel mixture and throttle cables cut; carburetor contained about 1/4 cup of fuel with no water or contamination. Oil filter clear of contaminants or metal.
No preaccident mechanical malfunctions or failures were found that would have precluded normal operation.
Medical and Pathological Information
The pilot was critically injured and survived for several hours following the accident. He passed away after being extricated from the airplane. An autopsy concluded the cause of death was multiple acute blunt traumatic injuries. Toxicological tests were negative for all substances tested.
Organizational Information
The USDA APHIS Wildlife Services program is responsible for animal damage management. Pilots are located in Colorado, Wyoming, Nebraska, New Mexico, and Texas, with flight experience ranging between 5,000 and 35,000 hours. The program includes about 35 pilots; 6 are based in Wyoming, of which 5 are full-time and one is a contract pilot.
Pilots are salaried and not compensated per flight, per flight hour, or per capture. The decision to fly rests solely with the pilot. Pilots travel to the training center in Cedar City, Utah, twice a year for their annual flight review and annual safety stand down.
Standard animal damage management flights have at least three phases: en route, surveillance (75–100 ft AGL), and predator mitigation passes (20–40 ft AGL, 60–70 mph). Pilots track targets out the side and rear windscreen; crew members shoot from the left side; the pilot positions the target on the left side. Most turns are to the left, but terrain may dictate right turns.
Following the accident, the flight program was grounded for an internal investigation. One internal and one external board of review made multiple recommendations. Another fatal accident occurred in New Mexico in 2015. Implemented safety items included automatic flight following, flight data monitoring, four full-time check airmen, flight reviews at 6-month intervals, standardized GPS reporting, required flight plans with mission profiles, and established across-target minimum speeds and minimum observation heights.