Opinion ID: 537057
Heading Depth: 3
Heading Rank: 1

Heading: Evidence of Design Defect

Text: 15 The expert evidence presented at the first trial concerning the design of the VW van was extensive and contradictory. The Roys contended that the swing-axle suspension system employed in the 1958 VW van was unstable and defective. William P. Thomas, who directed the race car programs for the Chevrolet Division of General Motors from 1956 to 1970, testified that when the van is turned, the VW suspension caused the back of the van to rise up and the wheels to drop. This reaction is known as jacking. The jacking exacerbated the high center of gravity and narrow wheel base that makes a van inherently more unstable than other vehicles. Dr. Igor Paul, a tenured associate professor of mechanical engineering at the Massachusetts Institute of Technology, also testified that the van would jack when turned. Dr. Paul suggested that jacking made the van susceptible to rolling over under circumstances that would not have caused similar American vans to roll. 16 The Roy's also presented to the jury the results of a bunji cord test developed by Paul O'Shea to monitor the reaction of vehicles when turned sharply. 3 Mr. O'Shea's test showed that the VW van would roll when turned sharply at between 18.2 and 18.4 miles per hour, whereas a 1967 Chevrolet van would not roll under the same conditions. 17 Dr. Paul and Mr. O'Shea further testified that the 1958 VW van had a tendency to change abruptly from understeer to oversteer. During an evasive maneuver, this tendency could cause the van to turn more sharply than the driver intended or expected, compounding the instability of the van. 18 VW's experts challenged the credibility and conclusions of the Roys' experts. Some testified that jacking and the change from understeer to oversteer did not make the van less stable. In fact, Edward Heitzman, an automotive test engineer, testified that several top sports cars are designed to change from understeer to oversteer at high G's and that this characteristic was helpful in an emergency. VW also showed the jury a videotape of tests it performed on its own van and comparable American vans. These tests indicated that the VW van was no less stable than other vans on the market. In short, each side presented persuasive evidence in support of its position. 19