N8715UCessna 172F · 1965

On October 5, 2013, about 1600 eastern daylight time, a Cessna 172F, N8715U, was substantially damaged during a forced landing following a total loss of engine power near Gainesville, Florida. The commercial pilot and pilot-rated passenger sustained minor injuries. The local banner tow flight departed Gainesville Regional Airport (GNV) about 1540. Visual meteorological conditions prevailed, and no flight plan was filed for the flight, which was conducted under the provisions of Title 14 Code of Federal Regulations Part 91.

The pilot stated that a preflight inspection of the airplane revealed no anomalies, and he subsequently departed on the flight and performed the banner pick-up. He proceeded toward the stadium around which he was to tow the banner, leveled the airplane at 1,200 feet above ground level (AGL), reduced engine power to 2,250 rpm, and leaned the mixture. He then extended the wing flaps to 10 degrees, and slowed the airplane to 50 mph. About 20 minutes into the flight, the pilot noticed that the airplane had descended about 100 feet, and he responded by increasing engine power and enriching the mixture, while observing that the oil temperature gauge indicated "hotter than normal." The airplane continued to descend and the oil temperature continued to rise into the red arc, and the engine subsequently experienced a total loss of power. The pilot released the banner, attempted to restart the engine to no avail, and then conducted a forced landing to a nearby field. He stated that due to "excessive airspeed" upon touchdown, the airplane bounced and impacted a parked truck, resulting in substantial damage to the fuselage and both wings.

The pilot held a commercial pilot certificate with ratings for airplane single- and multi-engine land, as well as an instrument rating; and flight instructor certificate with ratings for airplane single- and multi-engine, and instrument airplane. His most recent first-class Federal Aviation Administration (FAA) medical certificate was issued in September 2013. Following the accident, he reported 2,513 total hours of flight experience, of which 1,402 hours were in the accident airplane make and model.

The airplane was manufactured in 1965, and was equipped with a Lycoming O-360-A1A, 200 hp, reciprocating engine. Its most recent annual inspection was completed July 24, 2013. At the time of the accident, the airplane had accumulated 4,989 total hours of operation. According to the operator, the airplane was being operated on automotive fuel. Review of the airplane's airworthiness records showed that no supplemental type certificate had been issued authorizing the use of automotive fuels.

Following the accident, the airplane was removed from the site and subsequently examined by an FAA inspector. The engine exhibited little impact damage. The carburetor remained attached; however, the carburetor heat cable was disconnected and hanging free from the firewall. The magnetos remained attached and undamaged. The engine contained 7 quarts of oil. The oil filter was removed and opened, with no anomalies observed. The spark plugs were removed and appeared "blackish" in color. The electric fuel pump and starter were replaced, and the engine was secured for a test run. Utilizing the fuel onboard at the time of the accident, the engine started and ran for several minutes with no anomalies observed.

A fuel sample was taken from the carburetor prior to the test run, and sent for analysis at an aviation fuel testing laboratory. According to the laboratory, a Karl Fisher water test revealed "high" water content, and a microbial test was negative for bacteria and fungus. The quantity of the sample provided was insufficient to conduct distillation and flash point tests; therefore it could not be determined if the sample contained ethanol.

The 1553 recorded weather at GNV, 5 miles southwest of the accident site included wind from 090 degrees at 6 knots, 10 miles visibility, sky clear, temperature 31 degrees C, dew point 19 degrees C, and a barometric altimeter setting of 30.00 inches of mercury. Review of an FAA carburetor icing probability chart revealed the potential for serious icing at glide power given the atmospheric conditions present about the time of the accident.