N8254SCessna 150F · 1965

On March 20, 2015, about 0830 eastern daylight time, a Cessna 150F, N8254S, experienced a total loss of engine power near Grass Roots Airpark (06FD), Masscotte, Florida. The non-instrument rated private pilot subsequently made an off airport forced landing to a wooded area and was not injured. The airplane sustained substantial damage to both wings, empennage, and fuselage. Instrument meteorological conditions prevailed and no flight plan was filed for the flight destined for Kissimmee Gateway Airport (ISM), Orlando, Florida. The airplane was operated by a private individual under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight, which departed about 0815.According to a witness, the airplane taxied to the end of the runway 36 and visibility was limited due to the fog in the area. Then he heard the airplane depart the airport to the north about 0815. Following the accident, the witness talked to the pilot and stated that the pilot told him that after he departed the airport, the engine "sputtered, came back up, and then quit." According to another witness, the pilot stated he unsuccessfully attempted to restart the engine. Subsequently, the airplane landed in woods about a half mile from the airport.

When questioned by a local mechanic after the accident, the pilot reported that he did not use carburetor heat during the accident flight.

According to the Pilot/Operator Aircraft Accident/Incident Report (NTSB form 6120.1/2), the pilot indicated that the engine lost total power about 1,500 feet above ground level and that there were no mechanical malfunctions or failures with the airplane that would have precluded operation. However, he did not complete the narrative section of the report.

According to the pilot, he held private pilot certificate with a rating for airplane single-engine land. The pilot did not hold an instrument rating. He held a Federal Aviation Administration (FAA) third-class medical certificate that was issued on December 1, 2012, with a limitation of "must wear corrective lenses." He reported 2,400 total hours of flight time, of which, 400 were in the same make and model as the accident airplane.

According to FAA records, the airplane, manufactured in 1965, was registered to the pilot/owner in 2012. It was equipped with a Continental Motors O-200-A, 100-hp engine. According to the pilot, the most recent annual inspection was completed on March 16, 2014, and at that time, the airplane had accumulated 3,513.8 hours in-service.

Examination of the wreckage by a FAA inspector revealed that the airplane landed in a wooded area about a half-mile northeast of the runway. The left fuel tank was ruptured and an undetermined amount of automobile gas was draining from the tank. In addition, the right fuel tank was not ruptured and it contained an undetermined amount of automobile gas.

Examination of the engine revealed that engine continuity and thumb compression was confirmed on all cylinders by rotating the crankshaft. Both magnetos were tested, sparked on all towers, and no anomalies were noted. The spark plugs were removed from the cylinders, were light grey in color, and no anomalies were noted. The carburetor was fractured from the engine; but, examination of it revealed no anomalies. The fuel inlet screen was removed from the carburetor and no debris was noted.

The airport was privately owned at the time of the accident and did not have a control tower. There was one runway designated as 18/36. The turf runway was 3,400 feet long and 120 feet wide. The airport was about 105 feet above mean sea level and was surrounded by open pasture and farmland.

The 0835 recorded weather observation at Leesburg International Airport (LEE) , Leesburg, Florida, located approximately 11 miles to the north of the accident location, included calm wind, visibility less than one-quarter of a mile, fog, vertical visibility 200 feet, temperature 21 degrees C, dew point 21 degrees C; barometric altimeter 30.08 inches of mercury.

The carburetor icing probability chart from FAA Special Airworthiness Information Bulletin (SAIB): CE-09-35 Carburetor Icing Prevention, June 30, 2009, shows a probability of serious icing at glide power at the temperature and dew point reported at the time of the accident.

According to "The Use of Automobile Gasoline (MOGAS) in Aviation," a publication produced by Transport Canada, it stated that "the likelihood of carb icing while flying on mogas is higher. Although the severity of the carb icing and the methods to deal with it are similar for both Avgas and Mogas, its onset is likely to occur at higher ambient temperatures and a lower humidity with Mogas. In other words, conditions under which a pilot may feel there is only a slight risk for carb icing on Avgas may in fact be ideal for the formation of ice while using more volatile Mogas. This will result in the need to select 'carb heat on' in less severe icing conditions and for a longer duration while using Mogas."