ERA14LA401

The private pilot reported that he had flown the airplane to another airport earlier in the day and was returning to his home airport. The pilot stated that, when the airplane entered the downwind leg of the traffic pattern, he applied carburetor heat and 10 degrees of flaps. He added that, when he turned the airplane onto the base leg of the traffic pattern, he noticed an "unusually" low airspeed. The engine did not respond to throttle adjustments, so the pilot secured the carburetor heat, which had no effect. He then turned the airplane onto the final approach, and the propeller stopped. The pilot subsequently performed a forced landing to a cornfield, during which the right wing spar and propeller sustained substantial damage. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. A small amount of water was observed in the gascolator. The pilot reported that, when he initially sumped fuel before the first flight, he saw about 2 inches of water in a "standard" sump tube. The pilot also noted an additional 1/4 inch of water after adding 8 gallons of fuel. He further noted another 1/2 inch of water after adding 5 more gallons at the intermediate airport. Given the reported water in the fuel system before the first flight and after adding additional fuel, it is possible that water could have built up over time in the carburetor bowl and entered the engine as the airplane was making a descending turn. However, it is also possible that carburetor ice had formed given that the temperature and dew point at the time of the engine stoppage were conductive to serious carburetor icing at glide power. The pilot did not note if the engine rpm (fixed-pitch propeller) had decreased slowly but did note that the airspeed had decreased, indicative of lower rpm and, therefore, possibly carburetor icing. Also, although the pilot added carburetor heat in the landing pattern, with previously reduced power for the descent, carburetor ice could have already formed or the engine could have cooled to the point that initial heating efforts would not have provided heated air. However, with no substantive evidence that carburetor ice had formed and given the small amount of water found in the gascolator, the reason for the total loss of power could not be determined.

On August 20, 2014, about 2000 eastern daylight time, a Cessna 150G, N2466J, was substantially damaged during a forced landing while approaching Sky Manor Airport (N40), Pittstown, New Jersey. The private pilot was not injured. There was no flight plan for the flight, which originated at Princeton Airport (39N), Princeton, New Jersey. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91.According to the pilot, he flew from N40 to 39N earlier in the day, then later back to N40 at an altitude of about 1,500 feet above ground level. When he performed a preflight inspection of the airplane at N40, sumping both fuel tanks resulted in about 2 inches of water in a "standard" sump tube. The pilot also noted an additional ¼ inch of water after adding 8 gallons of fuel before departing for 39N. At 39N he noted another ½ inch of water after adding 5 more gallons of fuel. The pilot also stated that when he entered the downwind leg of the traffic pattern at N40 for runway 25, he applied carburetor heat and 10 degrees flaps. When he turned the airplane onto the base leg of the traffic pattern, he noticed an "unusually" low airspeed. The engine did not respond to throttle adjustments, so the pilot secured the carburetor heat, which had no effect. He then turned the airplane on to the final approach leg of the traffic pattern, and the propeller stopped. The pilot saw high tension lines, pulled back on the yoke, and the airplane just barely cleared the lines. The airspeed then decayed to the point where the airplane could not reach the runway, so the pilot turned it to the left and landed the airplane aligned with rows in a cornfield. During the landing, the airplane sustained damage to the right wing spar and the propeller. The responding Federal Aviation Administration (FAA) inspector noted a "small" amount of water in the gascolator, but did not examine the carburetor bowl. He was able to confirm engine compression but could not run the engine due to the bent propeller. The pilot did not note whether engine rpm had slowly decayed. The temperature and dew point, recorded at an airport about 15 nautical miles to east, were 24 degrees C and 14 degrees C respectively. For the ambient temperature and dew point, a carburetor icing probability chart found in FAA Special Airworthiness Information Bulletin CE-09-35 indicated "serious icing at glide power."