CEN13FA081

Witnesses reported seeing a low-flying airplane strike power lines near an auto dealership parking lot. There was a flash of light, and the airplane descended nose down into some parked trucks. When witnesses reached the airplane, the pilot was already deceased. However, none of the described injuries should have been immediately fatal. According to the autopsy report, the 92-year-old pilot’s death was attributed to severe coronary arteriosclerosis and atherosclerosis (quadruple vessel disease). Arteriosclerosis was noted throughout the main coronary arteries. The pilot most likely lost control of his airplane due to an acute coronary event related to his underlying severe coronary artery disease and that he was dead before the aircraft crashed. Federal Aviation Administration medical records, however, did not describe any coronary disease. The toxicology report did not find any medications associated with treated coronary disease. The pilot’s coronary disease likely was undiagnosed.

HISTORY OF FLIGHT On November 29, 20121, about 1715 central standard time, an Ercoupe 415-C (converted to a –D model), N720RC, collided with power lines and impacted parked trucks at Woodhouse Ford, Truck Mountain, 2546 S. Highway 30, just south of Blair, Nebraska. The pilot, the sole occupant on board, was deceased. The airplane was substantially damaged. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan had been filed. The flight originated from Scribner State Airport (KSCB), Scribner, Nebraska, about 1630, and was destined for KBTE. Six witnesses were interviewed by the Blair Police Department. The witnesses reported seeing a low-flying airplane strike power lines on the edge of the auto dealership parking lot with its landing gear. There was a flash of light, and the airplane descended nose down into some parked trucks. When the witnesses reached the airplane, there was no response from the pilot. One witness said there was a strong odor of fuel but he did not see any fuel leaking. The accident site was about 7.5 miles north of the Blair Municipal Airport (KBTE). PERSONNEL (CREW) INFORMATION The pilot, age 92, held a private pilot certificate with airplane single-engine land and rotorcraft-helicopter ratings. He was issued a limited third class airman medical certificate, dated June 28, 2011, that was valid for 12 calendar months. On his last application for medical certification, the pilot estimated he had accrued 5,400 hours total flight time. His last flight review was accomplished on April 22, 2012. AIRCRAFT INFORMATION N720RC (serial number 3658), a model 415-C (converted to a –D model), was manufactured by the Engineering and Research Corporation (ERCO), College Park, Maryland, in 1946. It was equipped with a used Continental C-75 engine (serial number 1263612) that was installed in 2002, driving a 2-blade, all-metal, fixed-pitch McCauley propeller. The last annual inspection was performed on December 18, 2011, at a tachometer time of 679.69 hours. At that time, the airframe had accrued 1,132.4 hours total time. At the accident site, the tachometer read 706.50 hours, or 1,159.2 hours total airframe time, and 26.81 hours since the last annual inspection. The previous annual inspection was performed on March 2, 2000. The previous owner told FAA inspectors that the airplane had flown 300 hours in the past 35 years. METEOROLOGICAL INFORMATION Weather recorded at KBTA at 1715 was as follows: wind, 140 degrees at 4 knots; visibility, 10 statute miles; sky condition, clear; temperature, 9 degrees Celsius (C.); dew point, 2 degrees C.; altimeter, 29.92 inches of Mercury. WRECKAGE AND IMPACT INFORMATION The airplane struck power lines on a magnetic heading of 360 degrees. The nose landing gear was located 38 feet, and the right main landing gear was located 66feet, from the power lines. The airplane impacted several parked trucks 130 feet from the power lines on a magnetic heading of 087 degrees. MEDICAL AND PATHOLOGICAL INFORMATION According to CAMI’s toxicology report, no carbon monoxide, ethanol, or drugs were detected. Cyanide testing was not performed. According to the autopsy report, death was attributed to severe coronary arteriosclerosis and atherosclerosis (quadruple vessel disease). Because of these findings, NTSB’s medical officer was consulted. According to her report, arteriosclerosis was noted throughout the main coronary arteries. The main coronary artery, the anterior descending branch of the left coronary artery, and the right coronary artery had pinpoint lumens as a result of atherosclerotic plaques and the circumflex branch was completely occluded. According to the death certificate, the cause of death was severe coronary arteriosclerosis and atherosclerosis. TESTS AND RESEARCH On January 24, 2013, the engine was partially disassembled and examined at the facilities of Beegles Aircraft Service, Greeley, Colorado. The oil dipstick was covered with black oil. Removal of the Nos. 1 and 3 spark plugs revealed normal wear. The bottom spark plugs were somewhat oil fouled. The rocker arms, push rods, cylinder heads, pistons, piston rings, connecting rods, crankshaft and camshaft were intact and were consistent with normal wear. The intake and exhaust valves were free. No anomalies were noted with the carburetor or air box. The oil screen was covered with thick black oil. When Federal Aviation Administration inspectors examined the engine at the accident site, they found the spark plugs were fouled and the engine oil was black. They also found the primer was unlocked and said it had been so for some time. The engine was only 26.8 hours since the last annual inspection. The annual inspection did not note an oil change.