On November 27, 2002, at 1000 Pacific standard time, an experimental Clyde K. Carrier Team 1400Z, N9190U, experienced a partial loss of engine power while in cruise flight and collided with a ditch during a forced landing near Woodland, California. The student pilot/builder was operating the airplane under the provisions of 14 CFR Part 91. The pilot sustained serious injuries, and the airplane was substantially damaged. Visual meteorological conditions prevailed, and a flight plan had not been filed. The personal local flight originated at Watts-Woodland Airport, Woodland, California, about 0950, with a planned destination of Yolo County-Davis (Woodland) Winters Airport, Davis/Woodland/Winters, California. In a written statement the pilot reported that about halfway to his intended destination, about 800 feet above ground level (agl), the engine experienced a loss of power. With a field below the airplane, the pilot initiated a sharp decent in an effort to make a forced landing on the field. About midfield, with the airplane about 15 to 20 feet agl, he noticed an irrigation ditch in front of the airplane. Upon touchdown, he stalled the airplane just before reaching the ditch. The wood reinforced plywood body of the airplane failed upon impact. The National Transportation Safety Board conducted a telephone interview with the pilot about 2 years after the accident. The pilot stated that the engine was operating all the way to touchdown, but he was unable to sustain level flight. After the accident, he conducted an examination of the airplane; he found no mechanical anomalies with the engine or airframe. He noted that prior to the accident flight he had installed new vented wing fuel caps, which were located in a negative pressure area of the wing. He opined that the low pressure area created a vacuum in the gravity fed fuel tank, restricting fuel flow to the engine, which resulted in a partial loss of power.