On July 7, 2008, about 1115 mountain daylight time, a Mooney M20E, N5652Q, was substantially damaged when it struck a parked vehicle during an aborted landing at the Big Creek Airport (U60), Big Creek, Idaho. The private pilot and his passenger were seriously injured. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the cross-country flight that originated from the Mc Call Municipal Airport, Mc Call, Idaho, about 30 minutes prior to the time of the accident. The pilot reported that upon arriving at U60, he over flew the airport and performed a low altitude pass over runway 19 to observe the condition of the runway. The pilot stated that while landing on runway 19, a 3,550-foot long and 110-foot wide turf runway, he thought the airplane was a little fast and applied power to abort the landing. The pilot added that as he initiated the go-around, the airplane reacted normally but did not gain enough altitude prior to colliding with a parked vehicle about 75-feet beyond the departure end of the runway. According to United States Forest Service (USFS) Personnel, witnesses adjacent to the accident site observed the airplane land about three-quarters down the runway prior to the pilot applying power and aborting the landing. Examination of the airplane by USFS personnel revealed that the left and right wing were structurally damaged. The fuselage aft of the cabin area was buckled and twisted. The pilot stated that there were no mechanical anomalies with the airplane prior to colliding with the parked vehicle. The automated surface observation system at MYL, located about 36 miles southwest of U60 reported at 1050, wind calm, visibility 10 statute miles, clear sky, temperature 19 degrees Celsius, dew point 07 degrees Celsius, and an altimeter setting of 30.12 inches of Mercury. Using the reported weather conditions at MYL and a measured field elevation of 5,743 feet mean sea level at U60, the NTSB investigator-in-charge calculated the density altitude to be 7,383 feet.