History of Flight
On July 13, 2014, at about 1725 eastern daylight time, an experimental, amateur-built Allen Steen Skybolt, registration N849CA, was destroyed after an inflight loss of control and collision with trees and terrain near Carrollton, Georgia. The commercial pilot and one passenger were fatally injured. The airplane was registered to a corporation and operated by the pilot under 14 CFR Part 91 as a personal flight. Day visual meteorological conditions prevailed, and no flight plan was filed. The local flight originated from West Georgia Regional Airport, Carrollton, about 1640.
According to reports, the pilot was on a local pleasure flight with his grandson. Several witnesses observed the airplane flying low, followed by a sudden pitch down or loss of control. Three witnesses reported the engine continued to run normally until impact, while two reported the engine was "sputtering" and/or "backfiring." Another witness reported the engine at "low power not idle."
Personnel Information
The pilot, age 70, held a commercial pilot certificate with ratings for airplane single-engine land, multi-engine land, and instrument airplane. On his medical certificate application dated May 12, 2014, he reported 2,710 total flight hours, including 35 hours in the preceding six months. His medical certificate included a restriction to wear corrective lenses.
A logbook provided by family showed the first entry on July 1, 2011, with a total forwarded time of 2,485.5 hours. The last entry was on June 25, 2014, in a Piper PA-31. Total logged time was 2,730.7 hours, including 1,454.1 single-engine and 395.0 hours in tailwheel airplanes. In the accident airplane, he had logged 6.1 hours over six flights since July 1, 2011, with the last flight on May 21, 2013.
Aircraft Information
The airplane was a Steen Skybolt, built by Charles Allen in 1975. It was an experimental, amateur-built biplane with tailwheel landing gear, powered by a Lycoming O-360-A1D engine rated at 180 horsepower at 2,700 rpm, fitted with a Hartzell HC-C2YK-1A two-bladed constant-speed propeller.
Maintenance records showed a conditional inspection on the airframe and engine on April 8, 2014, at an airframe total time of 860.75 hours. FAA records indicated the pilot acquired the airplane from the previous owner/builder in October 1999.
Meteorological Information
A surface observation at 1735 from Carrollton, Georgia (CTJ), about 9 miles west-northwest of the accident site, reported sky clear, wind from 180 degrees at 4 knots, visibility 10 statute miles or greater, temperature 90°F, dew point 68°F, and altimeter 30.08 inches of mercury.
Wreckage and Impact Information
The wreckage was located in a heavily wooded area. The airplane initially struck a white oak tree about 60 feet above the ground; the upper right wing section remained lodged in the tree. The remainder of the wreckage impacted the ground about 46 feet north-northeast of the tree. The wreckage path was about 105 feet long, oriented on a heading of 030 degrees magnetic. Numerous tree limbs up to 5 inches in diameter with smooth, angular cuts were present. A post-crash fire consumed most of the main wreckage. Components outside the fire area were free of soot or fire evidence.
All major structural and flight control components were accounted for. Flight control continuity was established from the cockpit control stick to the ailerons; fractures in aileron control rods were consistent with overload. Elevator and rudder continuity was confirmed from cockpit controls to control stick and rudder pedals. One of two welded steel brackets connecting the elevator trim tab to control cables was broken with fire and heat damage; it was sent to the NTSB Materials Laboratory.
The propeller assembly separated at the engine crankshaft, just aft of the propeller flange, and was found about 50 feet north-northeast of the engine. The propeller was the farthest component along the wreckage path. The crankshaft fracture showed overload signatures. The engine remained attached to the airframe by control cables.
Two sets of four-point seat belt buckles were found fastened in the cockpit; the webbing was consumed by fire. The metal fuel tank was ruptured and burned; the fuel cap was secure. The cockpit instruments were burned, and no useful information was obtained. The cockpit-mounted engine controls were found in the retarded (aft) positions.
Engine Examination
After recovery, the engine was examined in Griffin, Georgia. It was exposed to post-crash fire and burned or melted in several areas. Spark plugs showed normal electrode wear. Magneto cases were partially melted and untestable. The carburetor was heat-damaged; composite floats were charred but in place; the bowl was clean and dry with no residual fuel. Cylinders, valves, pushrods, and pistons showed no anomalies; power train continuity was established, and all components indicated normal operating signatures. The engine case, crankshaft, camshaft, and bearings were normal except for heat distress. No evidence of a pre-existing anomaly or malfunction was found.
Medical and Pathological Information
A postmortem examination of the pilot was performed on July 14, 2014, in Decatur, Georgia. The autopsy listed cause of death as "Multiple blunt impact injuries" and manner as "Accident." Forensic toxicology by the FAA CAMI laboratory found no ethanol in urine. Amlodipine was detected in urine but not blood; the pilot reported taking it on his medical application. Salicylate (aspirin) was detected in urine.
Tests and Research
The elevator trim tab and hardware were examined at the NTSB Materials Laboratory. The fracture surface showed intergranular features near the aft end and ductile overstress features in isolated areas after deoxidization, consistent with ductile overstress fracture.