SEA07LA088

The pilot was in the process of aligning the aircraft to enter the downwind for landing when he decided that there were too many aircraft in the pattern and that he would maneuver to the west of the field until the number of aircraft practicing landings was reduced. As he turned away from the airport, he reduced his power to about 1,850 to 1,950 rpm (about 1,500 rpm below normal cruise), and then began to loiter to the west of the traffic pattern. Soon thereafter the aircraft's engine quit, and the pilot began looking for a place to make a forced landing. During the landing sequence, the pilot had to maneuver over some power lines, and just after he did so, the aircraft touched down on some soft terrain and flipped over onto its back. The pilot did not apply carburetor heat when the engine lost power, and because he had not listened to the Automated Weather Observing System (AWOS), he was unaware that at the time of the power loss there was only a one degree difference between the temperature and the dew point. According to the DOT/FAA/CT-82/44 Carburetor Icing Probability Chart, the pilot was operating in ambient conditions where serious carburetor icing could be expected at both glide and cruise power.

On March 31, 2007, approximately 1905 Pacific daylight time, an experimental Johnson Zodiac CH601, N601J, nosed over during a power-off forced landing in a field near Arlington, Washington. The private pilot, who was the sole occupant, was not injured, but the aircraft, which is owned and operated by the pilot, sustained substantial damage. The local 14 CFR Part 91 personal pleasure flight, which departed Arlington Municipal Airport about 50 minutes earlier, was being operated in visual meteorological conditions. No flight plan had been filed. There was no report of an ELT activation.

According to the pilot, who failed to submit an NTSB Form 6120.1/2, he was in the process of aligning the aircraft to enter the downwind at Arlington Airport when he decided that there were too many aircraft in the pattern and that he would maneuver to the west of the field until the number of aircraft practicing landings was reduced. As he turned away from the airport, he reduced his power to about 1,850 to 1,950 rpm (about 1,500 rpm below normal cruise), and then began to loiter to the west of the traffic pattern. Soon thereafter the aircraft's engine quit, and the pilot began looking for a place to make a forced landing. During the landing sequence, the pilot had to maneuver over some power lines, and just after he did so, the aircraft touched down on some soft terrain and flipped over onto its back. In a post accident interview, the pilot said that he did not apply carburetor heat when the engine lost power, and because he had not listened to the on-field Automated Weather Observing System (AWOS), he was unaware that at the time of the power loss there was only a one degree difference between the temperature and the dew point (five degrees Celsius/four degrees Celsius).

According to the DOT/FAA/CT-82/44 Carburetor Icing Probability Chart, the pilot was operating in ambient conditions where serious carburetor icing could be expected at both glide and cruise power.