On June 8, 2014, about 1540 central daylight time, an experimental, amateur-built Steen Skybolt, N863SB, experienced a loss of engine power and impacted the runway at a private airstrip near Chapmansboro, Tennessee. The private pilot sustained serious injuries. The airplane sustained substantial damage to the right wing and firewall. Visual meteorological conditions prevailed and no flight plan was filed for the flight. The airplane was registered to a private individual and operating under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight, which was initiating at the time of the accident.
According to the pilot, he performed a preflight inspection with no anomalies noted. In addition, he sumped the fuel tanks with no debris noted in the fuel. He stated that he added about 5 gallons of fuel to make the fuel tanks approximately one-quarter full, which would have been "plenty" of fuel for the 15-20 minute intended flight. He turned on the fuel boost pump in order to start the engine, and then did not use it after the engine successfully started. After taxiing to runway 20, he performed an engine run up and everything was "fine." Then, after takeoff, during the initial climb, about 200 feet above ground level and over the departure end of the runway, the pilot noticed the engine was not producing full power. He elected to return to the runway and performed a 180-degree turn. Once over the centerline of the runway, the pilot attempted to add power, however, the engine did not respond. The airplane impacted the runway and a postimpact fire ensued.
According to witnesses, the airplane departed the private airstrip to the south. The engine ran "fine" until it reached the end of the runway, and then it began to run "rough." The airplane was about 300 feet above ground level when it lost partial power, and the pilot initiated a turn back to the runway. As the airplane neared the runway, the pilot "flared too high," the airplane "stalled," descended, impacted the grass strip, and a postimpact fire ensued.
A postaccident examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed that the airplane initially impacted the ground approximately 100 feet from where it came to rest on the turf runway. The fuselage, wings, and empennage were consumed by fire. The engine remained attached to the fuselage through the engine mounts.
The airplane was a single-place, welded tube fuselage, wooden wing biplane, with conventional type landing gear. According to FAA records, it was assembled in 2000 and registered to the pilot/owner in 2008. It was equipped with a Continental Motors, Inc. IO-470-L21B, 260 horsepower, engine. According to the pilot, the maintenance records were consumed by the postimpact fire. However, a mechanic that helped the owner maintain the airplane indicated that the engine had accumulated about 800 hours since overhaul.
The automated weather observation at Outlaw Field Airport (CKV), Clarksville, Tennessee, which was located 22 miles northwest of the accident location included wind from 360 degrees at 8 knots, visibility 10 miles, clouds broken at 4,000 feet above ground level, temperature 27 degrees C, dew point 16 degrees C, and an altimeter setting of 29.94 inches of mercury.
The engine was examined on June 12, 2014, by a manufacturer representative under the supervision of an FAA inspector. The engine, fuel system, and ignition system components were heavily fire damaged, which precluded functional testing. However, crankshaft and camshaft continuity was obtained from the propeller flange back to the accessory section and out to the rocker arms and valves. The engine control cables remained attached to the engine although the support structure was consumed by fire. Overall, the inspection of the engine did not reveal any anomalies that would have prevented normal operation and production of rated horsepower. For more information concerning the inspection, a field inspection report for the engine can be found in the public docket for this case.