1968 turned out to be a turning point in the history of Formula One, in terms of technicalities and safety. Wings were used on Formula One cars and aerodynamics really played a part in terms of the cars' performance, and 5 Grand Prix drivers were killed in this year – including Jim Clark, Mike Spence, Jo Schlesser and Ludovico Scarfiotti – Clark at a Formula 2 race at Hockenheim in a Lotus in April, Spence during practice for the Indianapolis 500 in a Lotus in May, Scarfiotti during a hillclimb event in Germany driving a Porsche sportscar in June, and Schlesser during the French Grand Prix driving a Honda in July. It was the last year where all the races were run on tracks with almost no safety modifications. The rather dubious events of the season included Schlesser's almost recklessly caused fatal accident at Rouen Les Essarts and the German Grand Prix run in atrocious rain and thick fog at the dangerous and long Nürburgring, a race that was even questioned at the start to be run in the almost intolerable conditions.