History of Flight
On July 12, 2018, about 1042 eastern daylight time, an experimental, amateur-built Rutan Defiant airplane, N17DR, was substantially damaged in an accident near Robertson Field Airport (4B8), Plainville, Connecticut. The private pilot was fatally injured. The airplane was operated as a personal flight under Title 14 Code of Federal Regulations Part 91.
A receipt recovered from the wreckage indicated the pilot purchased 20 gallons of 100 low lead aviation gasoline the day before the accident.
A GoPro camera mounted on the left rear wing faced aft over the trailing edge. The camera captured a view of a portion of the wing and the top of a flight control surface. At about 1030, a voice yelled "clear prop," and an engine started. About two minutes later, the second engine started. The pilot began taxiing at 1033. After noises consistent with engine runup and magneto checks on both engines, the pilot taxied onto the runway and began the takeoff roll about 1037.
The airplane became airborne near the 1,000-foot markers. During climb, the flight path moved left of the runway centerline, then corrected back, then moved right. About one minute after takeoff, the pilot initiated a left turn onto the crosswind leg for runway 2. The airplane continued onto a left downwind, followed by a left base leg. About 1041, the airplane crossed the runway 2 threshold, at which point the pilot initiated a go-around and engine noise increased. The airplane was left of the runway centerline as it climbed away.
The airplane then tracked more than 60° left of the runway centerline in an erratic, primarily descending left turn. Engine power was audible, with noise generally consistent with at least one engine producing power. The airplane continued in a steep left descending turn, estimated at times to be more than 60° of bank. Engine noise lessened as it descended over a housing development. The airplane impacted the ground about 1042. First responders arrived about six minutes later.
A witness on the ramp at 4B8 preparing for an instructional flight saw the accident airplane climb out from runway 2 and immediately veer left. The airplane was 150-200 feet above the ground near the fixed base operator. It continued in a steep left bank until it disappeared below the horizon and crashed. He may have heard at least one engine operating at the time. No smoke trailed the airplane.
Another witness with a sliding glass door open heard a low-flying airplane, went outside, and saw it flying directly over his condo. The airplane appeared in a "downward descent" about 40 feet above the ground. It then banked hard left, exposing the underside, and he heard a loud crash but did not see the impact.
Personnel Information
The pilot held a multi-engine rating valid only for the Rutan Defiant. He was listed in Federal Aviation Administration (FAA) airworthiness records as one of the airplane's builders.
Aircraft Information
The forward engine was originally delivered with a carburetor, but an aftermarket fuel injection system was added before installation on the airframe. According to the engine logbook, the engine had accumulated 4,421 hours as of September 21, 2000; no overhaul information was available. At installation on July 10, 2004, the logbook entry indicated 30.3 hours time in service. The aft engine was carbureted. When installed on July 10, 2004, the logbook entry indicated 1,009 hours since major overhaul; total time in service was not recorded.
Meteorological Information
According to the carburetor icing probability chart in FAA Special Airworthiness Information Bulletin CE-09-35, dated June 30, 2009, the temperature/dew point at the time of the accident was conducive to the development of serious carburetor icing at glide power.
Wreckage and Impact Information
The airplane collided with upsloping terrain inside a city-owned landfill about 0.4 mile southwest of the airport center. The wreckage path was oriented on a 150° heading, about 105 feet long and 25 feet wide. The airplane came to rest on a 060° heading. No fire occurred.
Flight control continuity was established from the aft-mounted wing/rudder assembly control surfaces to the cockpit. The left wing spar was broken and pushed aft about 20° at the outboard junction with the left fuel tank; the wing remained attached by fiberglass skin. The right wing remained attached to the fuselage. Control surface continuity from the forward-mounted canards to the cockpit was not established due to postimpact damage. The left elevator separated from the canard during the accident sequence. The right canard and elevator remained attached to the fuselage.
The nose landing gear separated during impact. The left and right main gear struts remained attached. The right main gear tire stayed on its strut; the left main gear tire separated and was found near the left wing tip.
The left and right fuel tank selector handles were in the OFF positions; first responders reportedly turned them off and removed the battery. Both fiberglass main fuel tanks were breached. Two gallons of clean, blue-colored fuel were recovered from the tanks. Fuel filler caps were secure, with pliable, undamaged seals.
The forward engine partially separated from the fuselage, remaining attached by wires, cables, and hoses. The propeller hub remained attached; the wooden blades shredded and splintered. The engine was not examined on scene due to wreckage inaccessibility.
The aft engine remained attached to the fuselage with the mount uncompromised. The propeller remained attached to the crankshaft; wooden blades were undamaged except for superficial non-rotational scratches. The engine was not examined on scene due to inaccessibility.
The front left 3-point seat belt remained attached to its buckles; the anchor was pulled away from the fiberglass wall by impact forces.
The wreckage was recovered to a secure storage facility for additional examination.
Forward Engine Examination
The forward engine was missing the oil filter assembly, oil dipstick, and a portion of the engine-driven fuel pump. The fuel servo was detached from its mount and hanging by its fuel-carrying lines. The engine was equipped with an aftermarket experimental fuel injection system. The magnetos both produced spark at all points when rotated manually. Spark plugs for cylinders 1 and 3 showed carbon fouling; cylinders 2 and 4 had normal signatures. Thumb compression and continuity were confirmed. A lighted borescope inspection of all cylinders was unremarkable. Fuel injection nozzles were unobstructed.
Aft Engine Examination
The aft engine was attached to its mount with impact damage. The carburetor was secured; a trace amount of fuel was in the float bowl. The fuel pump produced suction and compression. Left magneto timing was 26 degrees; right magneto 28 degrees before top dead center. Spark plugs for cylinders 2, 3, and 4 were heavily corroded. No signs of metal particulates. Oil suction screen clean. Signs of preexisting oil leak on cylinders 3 and 4. Thumb compression and valve train continuity confirmed.
Additional Information
Engine Data Monitor
The airplane was equipped with a J.P. Instruments EDM-760. Retrieved data contained 18 flights, including the accident flight (duration 12 minutes 18 seconds). Exhaust gas temperature (EGT) and cylinder head temperature (CHT) were recorded every 6 seconds. The final data set was recorded about 8 seconds before ground impact. EGT/CHT values during the 25-second period between go-around and impact showed no significant drop for either engine. The aft engine EGT showed a slight increase in the final 10 seconds; forward engine CHT increased slightly.
Sound Spectrum Study of GoPro Video
The audio portion was evaluated. Wind noise often obfuscated propeller blade passage frequency (BPF). In two portions, BPF reached about 78 Hz, equating to an engine speed of 2,340 rpm. It was not possible to isolate each engine individually, but there were no audio indications that one engine lost power relative to the other during the flight.
Medical Information
The Office of the Chief Medical Examiner of the State of Connecticut performed an autopsy. The cause of death was blunt impact injuries of the head and torso. FAA Forensic Sciences Laboratory toxicology testing was negative for carbon monoxide, ethanol, and drugs of abuse. Cyanide testing was not performed.