On September 1, 2001, at 1830 hours Pacific daylight time, a Sparke Air Command 582 Dual, N301CS, descended to the ground during the takeoff initial climb from a dry lake bed, 10 miles north of Gerlach, Nevada. The private pilot, who was the sole occupant, was uninjured, and the gyrocopter was substantially damaged. Visual meteorological conditions prevailed for the flight conducted by the pilot under 14 CFR Part 91. The experimental gyrocopter's flight was originating at the time, and no flight plan was filed. The pilot stated that the gyrocopter was still in the testing phase of the certification process. He had built it about 2 years ago and had been modifying it in order to reach an acceptable performance level. It had been flown approximately 10 times since construction, but the pilot stated that the engine and propeller combination was not giving him the performance needed to operate the gyrocopter safely. He had recently moved the pilot and passenger seats closer together to improve the airflow to the propeller, and was testing this latest modification at a dry lake bed near Gerlach. The gyrocopter was taken to the lake bed by trailer and assembled on site. The pilot made one test flight and returned to readjust the propeller pitch setting. On the second flight, the pilot departed upwind and climbed to 30 feet. When he turned to a downwind heading, he lost forward speed and the gyrocopter began to descend. The gyrocopter contacted the ground on the left tire, which resulted in a rollover. The rotor blades then contacted the ground and were destroyed. The pilot did not note any mechanical malfunction prior to or after the accident. A report of the accident on NTSB Form 6120.1/2 was not provided.