MIA06LA062 · Cessna 180

The pilot stated that he had topped off the airplane's fuel tanks in Gallatin, Tennessee, and he had 60 gallons of fuel onboard. He departed at 0625 central daylight time, climbed to 9,000 feet, and the flight's duration was 3 hours 30 minutes. He said he leaned the fuel mixture, observing fuel flows of about 10.5 to 11gallons per hour on his JPI analyzer, and that the quantity of fuel remaining never was less than 20 gallons. Upon reaching his destination airport he said he over-flew the airport to observe the winds, and then flew 6 miles south, twice circling his friend's house, and then returned to land. During the approach, while turning to base he applied 30 degrees of flaps, at which time the engine ceased operating. He said obstacles included trees and utility wires, and during the glide, after avoiding the trees, he selected 40 degrees of flaps in an attempt to balloon over the wires, and the airplane stalled and descended impacting the ground. During the pilot's report of the accident to the NTSB he stated that there were no mechanical failures or malfunctions to the airplane or any of its systems. A witness stated that he saw the accident airplane on downwind, rocking its wings, and he saw it on final approach and as it came over the trees. He said the propeller had stopped rotating, and as he continued watching, it appeared as if the pilot was trying to stretch the glide. He said he saw the airplane stall and descend, impacting the ground a short distance from the runway. On the day of the accident, an FAA inspector responded to the scene of the accident and found no evidence of fuel spillage at the scene. When the airplane was checked, the inspector found about 2 gallons of fuel in the left tank, and no fuel in the right tank. On March 10, 2006, an FAA licensed mechanic, under the supervision of the FAA inspector, conducted a detailed examination of the airplane's airframe and engine, and no anomalies were noted. The accident airplane was equipped with a Texas Skyways Incorporated conversion O-520 -U/TS engine. On July 17, 2007, a technician at Texas Skyways stated to the NTSB that Texas Skyways did not publish endurance documentation for their conversions because of the various models of engines they modified, and their variability in fuel consumption. He further stated that from his experience, climb to cruise fuel consumption for the O-520 U/TS engine, at a rate of climb of about 1,000 feet per minute, at full power, without leaning for changes in altitude would yield a fuel consumption of about 23 gallons per hour. He further stated that with leaning the mixture, and with other climb related adjustments, the average fuel consumption during the climb should be about 18 gallons per hour. At an altitude of 9,000 feet, the technician also estimated that the airplane should consume about 14 gallons per hour, while in cruise flight. In addition, the technician also said that JPI endurance data was consistent with the exhaust and cylinder head temperatures noted.

Verbatim NTSB analysis and probable cause from the NTSB dataset