On June 13, 2003, at 1000 mountain daylight time, a Diamond Aircraft Industries DA 20-A1, N630DA, was destroyed when it impacted terrain west of Eureka, Utah. The private pilot and his passenger received minor injuries. Visual meteorological conditions prevailed and no flight plan had been filed for the local flight being conducted under Title 14 CFR Part 91. The flight originated from Provo, Utah, at 0815. According to the pilot, he was maneuvering over the sand dunes between Eureka and Delta. The temperature was rising and it started getting "bumpy" so he elected to return to Provo. While flying over the mountains west of Eureka, approximately 1,000 feet above ground level, his "controls became mush." The airplane began descending rapidly, at which time the pilot "put in full prop[eller] and power, pitch[ing] for 75 kts." It was apparent that the airplane would not clear the rising terrain so the pilot reversed course towards the "canyon." The pilot stated the airspeed was "right above stall speed." Subsequently, the airplane collided with the trees. The airplane's empennage was separated from the fuselage. An examination of the airplane's systems revealed no anomalies.