History of Flight
On September 13, 2012, at approximately 1941 eastern daylight time, a Vans RV-7, registration N517DG, was substantially damaged when it collided with terrain near Cumming, Georgia. The private pilot and one passenger sustained fatal injuries. The airplane was registered to a corporation and operated under 14 CFR Part 91 as a personal flight. Day, visual meteorological conditions prevailed, and no flight plan was filed. The flight originated from Stoney Point Airfield (6GA0) in Cumming, Georgia, around 1927.
Review of radar data showed the airplane departed 6GA0 heading northwest. After about three minutes, it flew a figure-eight pattern while climbing to approximately 2,000 feet above mean sea level (msl). It then proceeded east-southeast for about 9 nautical miles (nm) before crossing the shoreline of Lake Lanier. The airplane turned south-southwest for about 6 nm, then initiated a left turn to the north. It reached a peak altitude of about 4,200 feet msl about 7 miles south of the accident site. While heading north, the airplane descended from 3,500 feet at 19:39:57 to 1,600 feet at 19:40:57, the last recorded radar return.
Witnesses observed the airplane maneuvering in the area before the accident. Several reported variations in engine noise shortly before the sound of impact. One witness stated the pilot appeared to be performing an aerobatic maneuver, adding that the airplane "spun wing to wing down" and disappeared behind trees.
Personnel Information
The pilot held a private pilot certificate with ratings for airplane single-engine land, airplane multiengine land, and instrument airplane. On his most recent third-class medical certificate application, dated January 5, 2011, he reported 730 total flight hours. A review of his personal logbook showed approximately 784 total hours, with about 660 hours as pilot-in-command.
Aircraft Information
The Vans RV-7 was a single-engine, low-wing, fixed tailwheel airplane, serial number 72314. It was powered by an experimental Aero Sport Power Ltd. IO-360-B1B engine rated at 180 horsepower at 2,700 rpm. According to maintenance records, the last condition inspection was performed on April 8, 2012, at a total aircraft time of 230.5 hours. The pilot was the listed builder of the airplane and held a certificated experimental aircraft builder endorsement.
Meteorological Information
The 1953 surface weather observation at Dekalb-Peachtree Airport (PDK), Atlanta, Georgia, about 23 miles southwest of the accident site, reported wind from 100 degrees at 3 knots, visibility 10 miles or better, clear skies, temperature 23°C, dew point 14°C, and altimeter setting 30.23 inHg.
Wreckage and Impact Information
The wreckage was found upright on a heading of 360 degrees. All structural components were accounted for at the scene, and there was no fire. No linear ground scar was present aside from the initial impact area. The propeller separated at the crankshaft and was partially embedded in the ground. One blade exhibited twisting, a forward bend, leading edge damage, and chord-wise scratches.
Flight control continuity was established for ailerons and rudder to the cockpit controls. Elevator continuity was confirmed except for a fractured tie rod connection, which showed signs consistent with bending overload. The engine mixture and propeller controls were in the forward positions; the throttle was found retarded. Both fuel tanks were breached, with evidence of spilled fuel beneath the wreckage.
Engine examination at the site revealed that all rocker covers and spark plugs were removed. The spark plugs indicated extended service life and normal combustion coloration. Manual rotation produced suction and compression on all cylinders, and valve rocker arms rotated normally. Accessory gears also rotated. Cylinders examined with a lighted borescope showed no defects. Fuel injector nozzles were clear and unobstructed. No anomalies were found that would have prevented the engine from producing rated power before impact.
Medical and Pathological Information
A postmortem examination of the pilot was conducted by the Georgia Bureau of Investigation on September 14, 2012. The autopsy report listed the cause of death as "Blunt force trauma of head, torso, and extremities" and the manner as "Accident." Forensic toxicology testing by the FAA CAMI lab was negative for carbon monoxide, cyanide, and ethanol. Naproxen was detected in the urine; this over-the-counter NSAID is used for pain and fever.
Tests and Research
The aircraft was equipped with an Advanced Flight Systems Inc. AF-3500EE multifunction display, which recorded aircraft attitude, altitude, heading, navigation, and engine parameters. The unit stored data on internal flash memory. It was sent to the NTSB Vehicle Recorders Laboratory for data extraction. External and internal examinations showed minor impact damage; data was retrieved normally.
The AF-3500EE contained 266 data points from September 5 to September 13, 2012. Date and time accuracy could not be verified because the clock was set by the operator. Data showed the flight path consistent with radar. Times were estimated by comparing the AF-3500EE track to radar data; the unit's clock was approximately 26 minutes and 48 seconds behind radar time.
At about 19:37:54, manifold pressure dropped from 26 inHg to about 11 inHg, coinciding with reduced fuel flow and airspeed. Altitude began decreasing at 19:38:18 and continued until the end of recording. Around 19:39:09, manifold pressure further decreased, and oil pressure fell from 72 psi to about 55 psi by about 1940. Approximately 23 seconds before recording ended, manifold pressure, fuel flow, oil pressure, and airspeed increased. During that period, altitude dropped from 3,030 feet to a last recorded value of 1,290 feet at 19:40:57.
Additional engine data showed exhaust gas temperature (EGT) increased for about one minute starting at 19:38:06. Cylinder head temperature (CHT) decreased until 19:40:46, then rose alongside manifold pressure and fuel flow until the end of recording.
Airspeed data revealed that at 19:39:09, the airplane was at 101 knots at 3,760 feet indicated altitude. Airspeed then gradually decreased to 59 knots at 2,920 feet at 19:40:41. It then increased to 119 knots at 19:40:51, with altitude at 1,990 feet. The last recorded airspeed was 81 knots at 1,290 feet at 19:40:57.