On September 5, 1970, in preparation for the Italian Grand Prix at Monza, Lotus driver and Formula One World Championship leader Jochen Rindt crashed during practice. He died on impact. By the end of the season, no one had been able to usurp his points lead, and he became F1's first and only posthumous World Champion.

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Rindt, an Austrian racer, started competing in 1961 and swapped to single-seater racing two years later. He made his F1 debut in 1964 and signed on first with Cooper, then Brabham, then Lotus.

The Lotus drive was a double-edged sword. On the one hand, Colin Chapman provided Rindt with a competitive car. On the other, the cars were notoriously unreliable; the Lotus 72 was still working out the worst of its growing pains, and Rindt was often a guinea pig for Chapman’s experiments with faulty wings.

Rindt wasn’t afraid to criticize the team for its faults. He hated the concept of the racing wing, which provided more aerodynamic downforce but which could also be unreliable and dangerous. He was vocal about the fact that he had little trust in Lotus, and that left him often butting heads with Chapman, who didn’t take kindly to the criticism.

During practice for the 1970 Italian Grand Prix, the Lotus team decided to remove the Lotus 72's wings. This was thought to make the cars even faster on an already high-speed track, but Rindt’s teammate John Miles felt that the car was unreliable and wouldn’t run straight.

Rindt didn’t report those problems, but during practice on Friday, Rindt crashed heavily at the Parabolica corner on his fifth lap. The crash barrier parted, and the vehicle slid under the barrier. Rindt, who didn’t wear the crotch strap of his five-point harness, slid down into the cockpit as a result of the impact. The force of the other belts slit his throat. Lotus had no idea what caused the crash.

Rindt’s death was a dark moment in F1's history and within the Lotus team’s. Chapman was earning a reputation as a visionary, but his cars were just as well known for being dangerous as the team attempted to stay ahead of the curve when it came to technical advancements.

That year, no one was able to usurp Rindt’s points lead, though Jacky Ickx certainly tried. Rindt’s wife, Nina, accepted her husband’s Championship on his behalf at the season-ending ceremony.