On August 05, 2018, about 0800 mountain daylight time, an experimental Jensen ICP Savannah airplane, N951RA, encountered a downdraft and impacted terrain short of the runway at the West Desert Airpark, Fairfield, Utah. The private pilot received minor injuries; the airplane sustained substantial damage to the right wing. The airplane was registered to and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. Day visual meteorological conditions prevailed, and no flight plan had been filed. The personal cross-country flight originated from Spanish Fork Airport Springville-Woodhouse Field, Spanish Fork, Utah, about 0700 and was destined for Fairfield. The pilot stated that while on the base leg of the traffic pattern, the airplane experienced a loss of lift. Despite his attempts to arrest the descent by adding full throttle, the airplane collided with the desert terrain short of the runway. The pilot opined that the airplane had likely encountered a severe downdraft and the engine power was not sufficient to overcome the resulting descent rate. He thought that the accident may have been prevented if he had configured the airplane to land in a steeper and higher approach combined with more airspeed. He further stated that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation.