The airline transport pilot was on a Title 14, CFR Part 91, personal flight which included taking off and landing at an off-airport site. In a written statement to the NTSB, the pilot reported that when the airplane touched down at the off-airport site, it bounced about 8 feet, and touched down again. He said with maximum braking he did not think he could stop the airplane in the landing area, and he added power to abort the landing. He reported that as the airplane became airborne, he encountered a downdraft, and the airplane collided with terrain. He said he should have aborted the landing sooner. He noted there were no known mechanical problems with the airplane prior to the accident. The airplane received substantial damage to the fuselage and both wings.