At about 1750 Eastern time, the airplane collided with terrain. The private pilot and three passengers were killed, and the airplane was substantially damaged. Visual conditions prevailed. At 1745, the pilot reported smoke in the cockpit and an engine-compartment fire. Between 1745 and 1749, ATC offered an airport three miles closer to the airplane than the destination, but the pilot declined, adding that the smoke was dissipating. At 1750, the pilot advised ATC he was going to land on a highway. The pilot then reported the airplane was on fire; this was the last transmission from the airplane. Review of radar data revealed that the airplane was at 3000 feet agl and 110 knots when radar contact was lost. A witness observed the airplane flying low and trailing black smoke. The engine stopped, and the airplane appeared to pitch up before rolling inverted and impacting terrain in a near-vertical attitude. The engine was 230 hours past its TBO.
