About 1:55 p.m., July 15, 1970, a chartered tour bus carrying a group of young people, aged 10 to 17, and counselors on a sightseeing trip was westbound on U.S. 22 (interstate 78, four lanes, limited access) about 12 miles west of Allentown, Pennsylvania, at a speed of (about) 55 miles per hour. A light rain was falling and had been preceded by a heavy shower.
While it was on a 2 degree curve to the right, just east of the Berks-Lehigh County line, the bus started to slide on the wet highway, then rotated 180 degrees clockwise through the guardrail and off the northern embankment. It overturned at the bottom of the embankment, ejecting 18 persons and pinning six of them under the left side of the bus. Seven children were fatally injured. No fire ensued.
The highway at the accident site when wet was found to have a skid number lower than the minimum recommended by Federal Highway Administration, and improper drainage resulting from inadequate maintenance of the median. It had a significantly high accident record involving skidding and loss of vehicle control. After the crash, a dramatic reduction in accidents resulted from the surface grooving, grading and paving of the median and shoulders, and replacement of the cable-type guardrail with a W-beam type.
The two left-rear tires of the bus were smooth; all others had adequate tread. Steering-system damage, found after the crash, could not be positively established as being pre-crash, in-crash, or post-crash induced.
The driver, a 45-year-old male, had a poor health history and a substantial record of traffic violations and accidents, but no specific health factor or driving error was involved in this crash.