NTSB Factual Report

On April 22, 2017, about 0915 eastern daylight time, an experimental amateur-built Sonex, N212AG, was substantially damaged during a forced landing, while attempting to land at the Leesburg Executive Airport (JYO), Leesburg, Virginia. The private pilot was not injured. The airplane was registered to and operated by the pilot as a 14 Code of Federal Regulations Part 91 personal flight. Marginal visual meteorological conditions prevailed near the airport about the time of the accident, and no flight plan was filed. The flight originated from JYO about 0845 and was destined for the Blue Ridge Airport (MTV), Martinsville, Virginia.

The pilot stated that he purchased the airplane three months before the accident but had to wait for the weather to improve before he could fly the airplane back to his home in Washington state. On the day of the accident, he topped off the airplane's 16-gallon fuel tank and reviewed weather conditions along his intended route of flight. He said it was "drizzly" but the ceiling was "good." The pilot conducted a preflight inspection of the airplane and performed an engine run-up before he departed. The pilot said when he got about 20 miles south of the airport, weather conditions deteriorated, and he elected to turn back to Leesburg. When he was on final approach to runway 35 at an altitude of 700 ft, the engine "just stopped." The pilot attempted to re-start the engine, but to no avail, and he made a forced landing just short of the runway. The pilot said he "ran out of airspeed" when the airplane was about 100 ft above the ground, and that it then "pancaked" onto the ground and slid for about 100 ft before coming to a stop.

The pilot said that the weather conditions (high humidity and visible moisture) were conducive to carburetor icing, but he did not apply carburetor heat until he tried to re-start the engine. Even then, he did not use full carburetor heat. When the airplane was recovered, the pilot said he drained 13 gallons of fuel from the fuel tank and it was absent of debris and water.

A postaccident examination of the engine revealed that it rotated freely, and compression and valve train continuity was established for each cylinder. A borescope was used to examine the inside of each cylinder and no anomalies were noted. No oil leaks were observed, and oil was present in the sump. The magnetic drain plug was removed, and it was absent of debris. External and internal examination of the distributor, rotor, and points revealed no evidence of anomalies that would have precluded normal operation. Neither of the two ignition coils displayed any evidence of damage. Examination of the sparkplugs revealed the electrodes were gray in color and exhibited normal signatures. The carburetor heat linkage and air door were functional. External and internal examination of the carburetor revealed no evidence of malfunction, the accelerator pump was functional, the floats showed no sign of leakage, and the float bowl contained fluid consistent with 100LL Aviation Gasoline. The fuel was then tested with water finding paste and no water was detected.

The weather conditions reported at JYO, at 0915, included wind 010° at 8 knots, visibility 10 miles, light drizzle, scattered clouds 1,600 ft, broken clouds at 2,400 ft, overcast clouds at 3,600 ft, temperature 55° C, dewpoint 54° C, and a barometric altimeter setting of 29.94 in Hg.

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

The pilot held a private pilot certificate with a rating for airplane single-engine land, and instrument airplane. His last FAA third class medical was issued on January 4, 2015. The pilot reported a total of 932 hours, of which, 2 hours were in the accident airplane.

NTSB Probable Cause

The pilot's failure to use carburetor heat appropriately, which resulted in a total loss of engine power due to the formation of carburetor ice.