A restaurateur and highly proficient amateur racer and hill-climb expert, Fischer enjoyed great success with his own single-seater Ferraris in the early fifties, run under the Ecurie Espadon banner.
Encouraged by his form in a Simca in 1949, and a sixth place in the Prix de Berne, sharing an HWM with Moss, he acquired a V12 Ferrari for the 1951 season, which he drove to great effect, particularly in non-championship events, finishing second at Bordeaux, third at San Remo and Syracuse and fourth in the Dutch GP. That season he also won F2 events at AVUS, Aix-les-Bains and Angouleme and enjoyed success in hill-climbs.
For 1952 Rudi managed to buy one of the latest T500 Ferraris, and did justice to it by finishing second in the Swiss GP and third in the German GP at World Championship level, while victories at AVUS and in the Eifelrennen were the highlights of a productive programme of lesser races.
It was some surprise when this excellent and most underrated driver quit international racing at the end of the season, although he continued to make occasional appearances, mostly in hill-climbs, into the late fifties.