On September 6, 2001, at 1120 eastern daylight time, a North American P51-D, N551CB, registered to Carrier Aviation, Inc., of Advance, North Carolina, and operated by the airline transport pilot, collided with terrain and caught fire six miles east of the Lincoln County Regional Airport in Lincolnton, North Carolina. The personal flight was conducted under the provisions of Title 14 CFR Part 91 with an instrument flight plan on file. Visual meteorological conditions prevailed at the time of the accident. The airplane was destroyed. The pilot sustained minor injuries, and the commercial pilot-rated passenger sustained serious injuries after both bailed out of the airplane. The flight departed Rowan County Airport in Salisbury, North Carolina, at 1103, en route to Springfield-Beckley Municipal Airport in Springfield, Ohio. While in cruise flight in instrument meteorological conditions at 8,000 feet, the pilot noticed coolant on the windshield and advised air traffic control of an engine overheat problem. The pilot requested nearest airport and weather information and was informed by air traffic control that Lincoln County Regional Airport was 10 miles behind the airplane's current position. The pilot declared an emergency and began a descent through the clouds, and the cockpit filled with smoke and condensation. At approximately 1,200 feet, the airplane broke out of the clouds, and the pilot saw an unpopulated wooded area and made preparations with the passenger to bail out of the airplane. As the pilot and passenger prepared to jump, the airplane's engine seized, the airplane snapped to the right, and the pilot and passenger were thrown clear. Both the pilot and passenger pulled their parachute ripcords and fell into the trees. Examination of the wreckage revealed the cowl flap was found crushed in the open position. A small amount of fluid was found in the radiator. The water pump and accessory assembly were damaged. The airplane's maintenance history could not be reviewed, because the registered owner failed to respond to repeated requests for the information.