On August 3, 1994, approximately 0750 mountain daylight time, N5641A, a Maule M-5-210TC, was substantially damaged when it impacted terrain near Mosca, Colorado. The private pilot received serious injuries. Visual meteorological conditions prevailed. According to the pilot/operator report, the pilot remembered taking off from his ranch airstrip to inspect his goats, but could not recall the landing or the accident. The pilot said he was familiar with his airstrip, having flown into and out of it for the past 15 years. The pilot added he believed he may have experienced a problem with the throttle. There were no known witnesses to the accident. According to the Federal Aviation Administration inspector who went to the accident site, the beginning of tire tracks was noted 500 feet down the 800-foot dirt runway. The inspector said the tire tracks went off the west end of the runway and through two fences. Past the fences was a highway, but there were no contact marks on it. An additional set were found on the other side of the highway that went through a third fence. The tracks terminated at the airplane, which was located against an abandoned railroad track berm. The inspector reported finding no evidence of mechanical failure or malfunction of the engine or flight controls.