Following a business arrangement with Alejandro de Tomaso, Williams switched to a newly designed De Tomaso chassis for the 1970 Formula One season. Unfortunately for Courage, the De Tomaso proved to be overweight and unreliable, and only a third place in the non-championship International Trophy alleviated a poor string of results in the early season. The Dutch Grand Prix seemed to be going slightly better, with Courage qualifying in ninth place around the Zandvoort Circuit. Running in the middle of the field, the De Tomaso's front suspension or steering broke on the bump at Tunnel Oost, causing the car to suddenly go straight on instead of finishing the high-speed bend. It then rode up an embankment (one of the Zandvoort dunes) and disintegrated, with the engine breaking loose from the monocoque, upon which it burst into flames. To lighten the De Tomaso, magnesium was used in its chassis and suspension. The magnesium burned so intensely that many nearby trees and bushes were set alight.