On July 28, 2001, approximately 0750 mountain daylight time, a Cessna 172RG, N401TA, registered to Top Notch Aviation, Inc., of Austin, Texas, was destroyed when it collided with terrain while climbing 9 miles east of Gunnison, Colorado. The private pilot and two passengers were seriously injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the personal flight being conducted under Title 14 CFR Part 91. The flight originated at Gunnison approximately 0730. According to the pilot's accident report, he took off from Gunnison County Airport (elevation 7,673 feet msl), climbed to 9,700 feet msl (above mean sea level), and decided to cross the mountains. The airplane encountered a "300 foot updraft, and then a 2,000 foot downdraft." The pilot said he decided to "land the plane without the use of the landing gear on the side of the mountain. All passengers walked away." According to one passenger, this was the pilot's first time flying in the mountains. It was their intention to follow State Route 114 to Saguache, Colorado, then direct to Amarillo, Texas. The airplane was at 80 knots and 8,300 feet as they approached Flat Top Mountain. The pilot pulled back on the control yoke in an attempt to gain sufficient altitude to clear the peak but the airplane was slow in responding and "we literally came straight down" and "the belly [struck the ground] pretty hard." He and the pilot were able to extricate themselves from the airplane but were seriously injured and their movements were restricted. The injured second passenger was unable to extricate himself, but did manage to retrieve his cellular telephone and call for help. According to rescue personnel, all three occupants sustained fractured vertebrae. They reported the accident site to be at an elevation of 8,510 feet. The accident site and reported route of flight were plotted on a Denver Sectional Chart. Terrain in the immediate vicinity of the accident site rises to 9,000 feet msl. State Route 114 crosses the Cochetopa Hills via North Pass, the summit being 10,149 feet. The highway is bordered by numerous 10,000 and 11,000-foot peaks. The straight line distance between Gunnison County Airport and the accident site was 9 nautical miles. The difference in accident elevation and airport elevation (8,510 - 7,673) was 837 feet. This computes to a climb rate of 93 feet per nm. The airplane was estimated to weigh 2,670 pounds at takeoff (maximum certificated gross weight is 2,650 pounds). This was based on aircraft papers retrieved at the accident site, the pilot's medical certificate weight, the passengers' weights from hospital admission records, and estimated weight of baggage removed from the airplane. Using the Gunnison altimeter setting of 30.49 inches of mercury, the pressure altitude was computed to be 7,103 feet msl. Referring to the Cessna 172RG "Maximum Rate of Climb" chart and interpolating, it was computed that the airplane was capable of achieving a climb rate of 464 fpm (feet per minute). At a climb speed of 79 knots, it was computed that the airplane was capable of climbing 352.4 feet per nm.