Chugiak, AK, USA
N7JQ
ANTARES MA-32
The solo private pilot was on a personal local flight in a ski-equipped experimental light sport weight-shift-control, pusher aircraft (Trike) under Title 14, CFR Part 91. He died as a result of the accident, and was found about 10 feet from the aircraft. The accident aircraft was found near a railroad track by the crew of a passing train. According to his logbook entries, the pilot had 233 hours of powered flight experience, and logged 4.5 hours of flight in the past 15 months. According to a friend, the accident flight was his first flight of this year. No evidence of a current required aircraft annual condition inspection was discovered. The pilot had replaced the aircraft’s original engine with a more powerful 100 horsepower engine, and it was also equipped with a digital video camera mounted on the forward support strut facing forward. A review of the accident flight video showed the control tube upper support cables moving in and out of the left and right sides of the camera’s field of view. The nose of the aircraft and the single front ski could also be seen in the video. Before the accident, the aircraft was flying at a low altitude over snow-covered flats to the west of the accident site. It made a steep climbing right turn to the east and continued to climb at a very steep angle. The angle of bank approached 90 degrees relative to the horizon, the climb appeared to stop, and the nose fell through the horizon rapidly. A frame-by-frame review showed that prior to the nose falling through the horizon, the wind screen was pushed forward into the cameras field of view, and then to the left, indicating that the aircraft was descending backward. The camera recorded an event consistent with a aerodynamic tumble. During the tumble, the camera mount broke and the camera drifted away and fell alongside the tumbling aircraft, continuing to record the aircraft. The aircraft had been equipped with automotive style lap belts and shoulder harnesses, with plastic push-button receiver type buckles. The pilot's lap belt buckle came apart during the tumble, likely due to the airframe flexing between the shoulder harness mast attachment and the floor mounted lap belt attachment, which placed a tension load on the pilot's lap belt buckle. The camera attained a position below the aircraft, and showed the pilot separate from the aircraft above the treetops. The accident aircraft was originally constructed as a two-place ultralight trainer, and later transitioned to experimental light sport category aircraft. Transitioned aircraft were not subject to the construction standards of ELSA, and therefore there was no standard for occupant restraint systems.
HISTORY OF FLIGHT On March 13, 2010, about 1700 Alaska daylight time, a ski-equipped Antares MA-32 experimental light sport weight-shift-control aircraft (commonly referred to as a Trike), N7JQ, sustained substantial damage when it impacted terrain, about 2 miles north of the Birchwood Airport, Chugiak, Alaska. The aircraft was being operated by the pilot as a visual flight rules (VFR) local flight under Title 14, CFR Part 91, when the accident occurred. The solo private pilot died as a result of the accident. The time of departure from the airport is unknown, and no flight plan or flight following procedures were in effect. During an interview with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on March 14, a law enforcement officer (LEO) of the Alaska Railroad said about 0800 on March 14, a passing train engineer saw a flashing light on the west side of the railroad track, about 2 miles north of Birchwood Airport. When the LEO arrived at the site, he said he found the aircraft and the deceased pilot. The flashing light was an anti-collision strobe light attached to the nose of the aircraft. During an interview with the IIC on March 14, a friend of the pilot said the pilot had left home on March 13, to go cross-country skiing, and when he did not return home that evening, he was reported to authorities as a missing skier. Another friend said the pilot told him he was going to take the trike for a flight after skiing, but that friend was not aware that the pilot had not returned from the flight. Birchwood Airport is an uncontrolled general aviation airport, and the friend he had told about flying the aircraft suspected he would have returned about 1700. There are no known witnesses to the actual impact. INJURY TO PERSONS The solo pilot died as a result of the accident. DAMAGE TO AIRCRAFT The aircraft received substantial damage by impact with terrain. PERSONNEL INFORMATION The 54 year old pilot held a private pilot certificate with a weight-shift-control rating, and a experimental light sport repair and inspection certificate. His most recent third-class medical certificate was issued on May 28, 2009, and contained a limitation for corrective lenses. According to the pilot’s personal flight logbook, he had 233 hours of powered aircraft flight experience. He logged 3 hours of flight in the trike in June 2009, and one and one-half hours of flight in the trike in August of 2009. No other powered aircraft flight time was logged. According to a friend, the accident flight was his first flight of 2010. AIRCRAFT INFORMATION The accident aircraft was an experimental light sport Antares MA-32 weight-shift-control aircraft, and according to FAA records, was purchased by the pilot in August 2007. The pilot attended a certified maintenance course in June 2006, and obtained a repair and inspection certificate for weight-shift-control aircraft. The last record of the required annual condition inspection discovered was dated September 2007, and indicated that the inspection was completed by the previous owner, and that the aircraft had 259.4 hours of use at the time the inspection was completed. There was no record of a current annual condition inspection. According to friends, the pilot had replaced the aircraft’s original engine with a much more powerful 100 horsepower engine. METEOROLOGICAL INFORMATION The closest weather reporting station was the automated weather station at the Birchwood Airport, Chugiak, Alaska, about 2 miles southwest of the accident location. The automated weather observation at 1656 ADT reported the wind as calm, visibility 10 statute miles, clear skies, altimeter 29.35 inches of mercury, temperature 18 degrees F, and dew point 9 degrees F. COMMUNICATIONS There were no known communications with the airplane. The aircraft was equipped with a 121.5 MHz emergency locater transmitter (ELT). The ELT was found to be operational, but at the accident site the IIC found its ON/OFF switch in the off position. WRECKAGE AND IMPACT INFORMATION On March 14, 2010, the NTSB IIC, along with an FAA aviation safety inspector from the Anchorage Flight Standards District Office (FSDO), traveled to the accident site, and examined the wreckage. The accident site was in a small snow-covered clearing, northeast of the Birchwood airport. The clearing is oriented predominately north/south with a railroad track along the east edge of the clearing, and steep ascending terrain on the east side of the track. The western edge of the clearing is bounded by a tree line atop a bluff overlooking a saltwater inlet. The wreckage was located adjacent to the tree line on the west side of the clearing, and the deceased pilot was located about 10 feet south of the wreckage. The aircraft was a rear engine (pusher), weight-shift-control aircraft. The tricycle landing gear had been fitted with snow skis. It had impacted terrain backwards, and the pusher engine was partially buried in the snow. The IIC noted that all the major components and control surfaces were present. The nose of the aircraft was pointed to the west, and upward about 50 degrees. The aircraft has a single wing, which is articulated at its center on a mast. The single articulated wing lay on the ground behind, or to the east, of the fuselage/carriage, and was folded in half. The wing is fabric with internal aluminum ribs, and had several large tears. The center nose fitting of the wing was fractured, allowing the wing to fold in-half mid span. The wing is attached atop a mast which serves as the attachment between the fuselage/carriage forward and the pusher engine aft. The lower carriage frame, which is welded to the mast, was broken on both sides of the mast where the frame tubes had been drilled to mount engine linkages. A king post is mounted atop the wing, and provides support for the wing's upper support (flying) wires. All the upper flying wires were attached and intact. The lower wing strut wires attach at under-wing attaching points to a central control tube, which allows the pilot to control the wing's position in-flight. All the lower strut wires were intact and appropriately attached. The center control tube, which was broken in-half, contained an internal safety wire which was severed. The composite three-bladed propeller was intact with minor damage to the leading edges, and fuel was present in the engine and fuel tank. The IIC noted that the distance between the aircraft, lack of marks in the snow between the aircraft and the pilot, and the pilot's injuries were consistent with the pilot having separated from the aircraft prior to the impact. The aircraft had been equipped with automotive style lap belts and shoulder harnesses, with plastic push-button receiver type buckles. The shoulder harness was attached to the upper part of the mast, and the lap belt was attached to the floor framework. The lower end of the shoulder harness was attached to the lap belt on either side of the lap belt buckle. The pilot’s lap buckle had come apart. The accident aircraft was originally constructed in 2001 as a two-place ultralight trainer under CFR Part 103. With the advent of light sport category aircraft in 2008, CFR Part 103 aircraft were restricted by regulation to single-place aircraft. Two-place ultralight trainers were transitioned to experimental light sport category aircraft (ELSA). Transitioned aircraft were not subject to the construction standards of ELSA, and therefore there was no standard for occupant restraint systems. The aircraft wreckage was loaded on a truck, and moved to a hangar at the Birchwood Airport. MEDICAL AND PATHOLOGICAL INFORMATION A postmortem examination of the pilot was conducted under the authority of the Alaska State Medical Examiner, 4500 South Boniface Parkway, Anchorage, Alaska, on March 15, 2010. The examination revealed the cause of death for the pilot was attributed to multiple blunt force injuries. The FAA's Civil Aeromedical Institute (CAMI) conducted a toxicological examination on April 22, 2010, which showed Acetaminophen and Ibuprofen in the urine. ADDITIONAL INFORMATION AND RESEARCH During discussions with weight-shift-control aircraft pilots and associates/friends of the pilot the subject of an aerodynamic tumble was discussed. The tumble mode is a peculiarity of weight-shift-control aircraft. It is a departure from controlled flight leading to a nose-down pitch autorotation, with known rotation rates up to 400 degrees per second. Following a series of fatal weight-shift-control accidents the United Kingdom's Air Accidents Investigations Branch (AAIB), commissioned a study of the tumble mode in 1997, a copy of which is included in the docket of this report. Following a review of the United Kingdom (UK) report the accident aircraft was re-examined by the IIC. The IIC noted that many of the results of the tumble noted in the UK study were present in the accident aircraft. During the initial investigation friends and family of the pilot believed the aircraft had been equipped with a digital video camera, however, no camera was initially found. Several weeks after the accident, when most of the snow in the area had melted, family members recovered the camera from the accident site. The camera was given to a mutual friend who downloaded the images. On June 3, the IIC and another NTSB investigator reviewed the video recording. The camera had been mounted on the forward support strut facing forward. The control tube upper support cables could be seen moving in and out of the left and right sides of the camera’s field of view. The nose of the aircraft and the single front ski could also be seen in the video. Shortly before the accident, the aircraft was flying at a low altitude over the snow-covered flats along the inlet to the west of the accident site. The aircraft made a steep climbing right turn to the east and while continuing to climb at a very steep angle, the aircraft angle of bank approached 90 degrees relative to the horizon in the video. The climb then appeared to stop, and the nose fell through the horizon rapidly. A frame-by-frame review of the tumble showed that prior to the nose falling through the horizon, the wind screen was pushed forward into the camera's field of view, and then to the left. During the tumble, the camera mount broke and the camera departed the aircraft, but it continued to record the aircraft as it fell alongside. During the descent, the camera attained a position below the aircraft, and showed the pilot separate from the aircraft above the treetops. The treetops were estimated to be 40-60 feet tall.
The pilot's decision to pitch the aircraft excessively during a steep climbing maneuver, resulting in a loss of control and an aerodynamic tumble.
Source: NTSB Aviation Accident Database
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