About 7:25 a.m., central standard time, on November 16, 1980, an intercity-type bus was traveling south on U.S. Route 183, a two-lane rural highway in south-central Texas. It was raining and the pavement was wet. As the bus approached and attempted to negotiate a curve to the left, the rear tires of the bus lost traction. The bus skidded across the opposing traffic lane and onto the shoulder before it could be steered back onto the highway. As it crossed the highway again, the bus spun 180 degrees and slid into a drainage ditch where it struck the side of the ditch and overturned onto its left side. Two bus passengers were killed, and the busdriver and 35 passengers were injured.