History of Flight
On September 26, 2010, at 1059 eastern daylight time, a Cessna 150F, N7915F, was substantially damaged when it impacted trees and terrain while maneuvering near Sweetwater, Tennessee. The flight originated from Cobb County Airport (RYY), Marietta, Georgia, about 0945, and was destined for Knoxville Downtown Island Airport (DKX), Knoxville, Tennessee. The pilot, a friend of the owner, had borrowed the airplane for personal travel. On September 24, he had flown from DKX to Columbus-Lowndes County Airport (UBS), Columbus, Mississippi, and on September 25 from UBS to RYY, reporting the airplane performed well. During the accident flight, two witnesses heard the airplane "sputter" before it crashed into a ridgeline; one noted an easterly approach and the other described foggy conditions. Radar data showed the target at 3,900 feet mean sea level (msl) at 1039, descending to 3,000 feet by 1044, maintaining that altitude until 1058, then executing a right turn followed by a descending left turn. The last radar return was at 1059:28 at 1,600 feet msl, about 1/4 mile northwest of the accident site.
Personnel Information
The 64-year-old pilot held a private pilot certificate with a single-engine land rating but no instrument rating. His most recent FAA third-class medical certificate was issued July 22, 2009. According to his logbook, he had 329.6 total flight hours, including 24 hours of simulated instrument experience, none within the preceding 10 months, and no actual instrument time. He had flown 5.6 hours in the 90 days prior, excluding the recent flights.
Aircraft Information
The two-seat, high-wing, fixed-gear Cessna 150F (serial number 15064015) was built in 1966. It was powered by a Continental O-200, 100-horsepower engine with a McCauley fixed-pitch propeller. The last annual inspection was on July 3, 2010, at which time the airframe and engine had 3,582.8 total hours; the engine had 1,986.8 hours since overhaul. Since the inspection, about 13 hours had been flown.
Meteorological Information
The pilot had filed a VFR flight plan for the previous day's flight from UBS to RYY and was briefed on adverse weather. No record existed of a briefing for the accident flight. At RYY at 0947, conditions were calm winds, 10 miles visibility, scattered clouds at 700 feet, an overcast ceiling at 4,800 feet, temperature 21°C, dew point 19°C, and altimeter 29.92 inHg. At Monroe County Airport (MNV), located at 1,031 feet msl, at 1056, winds were from 320° at 4 knots, visibility 9 miles, overcast ceiling at 600 feet, temperature 17°C, dew point 17°C, and altimeter 29.93 inHg.
Wreckage and Impact Information
The wreckage lay at about 1,300 feet msl. All components were present. Two scarred trees oriented north-south marked the impact; no debris path was noted. The airplane came to rest upright, left wing down, nose low, on a heading of about 060° magnetic. The empennage was intact with minor elevator and rudder damage. Both wings were attached; the left aileron was up, the right aileron down, and flaps were retracted. The left fuel tank was approximately three-fourths full of bright, clear 100LL fuel. The cockpit was crushed. The throttle was near idle, mixture rich, carburetor heat off, magneto switch set to "Both," airspeed indicator indicated 170 knots, and the attitude indicator was tumbled. Control continuity was confirmed for ailerons, elevator, elevator trim, and rudder. The elevator trim jackscrew measured a 5-degree tab-up position. The engine and propeller remained attached. One propeller blade showed s-bending and chordwise scratches; the other had chordwise scratching and polishing. The propeller rotated freely, and engine continuity and compression were verified. Spark plugs had intact gray electrodes. The carburetor floats and needle valve were intact.
Medical and Pathological Information
An autopsy was performed on September 27, 2010. Toxicological testing detected propranolol in the pilot's liver and blood. On his most recent medical application, the pilot had indicated "slightly high B P."
Additional Information
A handheld GPS receiver recovered from the wreckage provided track points consistent with radar data but no time or altitude information. FAA Advisory Circular 60-4A notes that during low visibility, pilots are vulnerable to spatial disorientation when supporting senses conflict with flight instruments.