History of Flight
On February 25, 2015, at about 1624 central standard time, an experimental amateur-built Rose Thunder Mustang, registration N7TR, struck terrain approximately 2 miles southwest of Helotes, Texas. The commercial pilot, who owned and operated the aircraft, sustained fatal injuries. The flight was conducted under 14 CFR Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed. The airplane departed Boerne Stage Field Airport (5C1), San Antonio, Texas, about 1604.
A witness residing about half a mile northeast of the accident site reported hearing and then observing the airplane approaching from the northeast, flying southwest at about 600 feet above ground level. The area was unpopulated, near the Government Canyon State Natural Area. When the airplane had traveled about half a mile southwest, the witness saw the nose rise vertically while banking left. The airplane became fully inverted and began descending in a left bank. The witness expected the airplane to recover and depart northeast, as seen previously, but instead it continued descending nearly straight down until disappearing behind a hill and trees, followed by a thud. The engine sounded full power throughout, with no indication of power loss. There was no postimpact ground fire.
Personnel Information
The 66-year-old pilot held a commercial certificate with single-engine land, multi-engine land, and instrument land ratings. His logbook showed 3,992 total flight hours, with 58 hours in the accident airplane. He held a second-class medical certificate issued in April 2014.
Aircraft Information
The airplane was a single-engine experimental amateur-built Rose Thunder Mustang, serial number GHTM002, manufactured in 1998. Maximum gross weight was 3,200 lbs, seating two. It was powered by a Ryan Falconer V-12 engine producing 640 horsepower. The last conditional maintenance inspection occurred on May 1, 2014, at 469 total airframe hours. The engine had 140 hours since last overhaul. The airplane was a scaled replica of a North American P-51D.
Meteorological Information
At 1551, the surface observation at San Antonio International Airport (SAT), about 12 nautical miles east, recorded: wind 320 degrees at 4 knots, visibility 10 statute miles, few clouds at 2,500 feet, temperature 19°C, dew point 3°C, altimeter 29.81 inches of mercury.
Wreckage and Impact Information
The airplane impacted hard, rocky terrain with juniper, mesquite, and oak trees. The debris field lay on a 015-degree magnetic heading. Most of the composite wreckage was within 300 feet of the initial impact point. Flight control cable continuity was not established due to multiple breaks and fragmented surfaces; all breaks showed overstress characteristics.
The engine was found about 730 feet north-northeast of the initial impact point. Visual examination revealed separation of the intake manifold, ignition harness, reduction gearbox, and propeller. No preimpact crankcase breach was found. The oil pan was separated. Examination of the crankshaft, connecting rods, pistons, and cylinders showed no evidence of lubrication or heat distress.
The four-bladed propeller hub and reduction gearbox were located about 600 feet from initial impact. Three wooden blades separated at the hub; the fourth separated about 6 inches from the hub. The fractured blades were not located.
Tests and Research
Two MoTec M48 Engine Control Units (ECU) and a Vision Microsystems EC100 were examined by the NTSB Vehicle Recorder Division. The EC100 could not record relevant data. The MoTec ECUs logged engine parameters at one sample per second, containing 10,638 data points. The accident flight, from data points 9,425 to 10,595, lasted about 19.5 minutes. Data showed engine operation until the last recorded point. At 10,570 elapsed seconds recorded, barometric reference began increasing, consistent with descent. The ECU lost power at 10,595, with all parameters indicating the engine was running at that time.
Medical and Pathological Information
Autopsy performed on February 26, 2015, determined the cause of death as blunt force injuries from the crash. A forensic toxicology report by the FAA Civil Aerospace Medical Institute was negative for all tested substances.