BRABHAM BT46B Alfa Romeo

   The 1978 World Championship season was dominated by Colin Chapman’s innovative ground-effect Lotus 79. Brabham owner Bernie Ecclestone instructed his designer, South African engineer Gordon Murray, to find a solution to counter Lotus’s superiority. However, the bulky Alfa Romeo flat-12 engine prevented the use of the underbody venturi tunnels characteristic of wing cars, forcing Murray to seek an alternative approach.

BRABHAM BT46B, Niki Lauda
Anderstorp, Swedish GP 1978

   The solution was suggested by Gary Anderson and David Cox, Murray’s assistants, who proposed a rear-mounted fan capable of creating an artificial vacuum to "stick" the car to the ground. However, the idea was not entirely original, it was "borrowed" by Cox, who, during discussions with Tyrrell about a potential job opportunity, had seen a similar project inspired by the Chaparral 2J, a 1970 Can-Am car. In Formula 1, the use of a fan driven by an auxiliary engine was prohibited, as it was considered a movable aerodynamic device and would effectively increase the engine's total displacement.BRABHAM BT46B, Niki Lauda

Anderstorp, Swedish GP 1978

BRABHAM BT46B, Niki Lauda
Anderstorp, Swedish GP 1978

   After carefully studying the regulations, Murray developed a legal workaround: the fan was connected to a radiator, officially making it a cooling device. Its movement was powered by an extension of the crankshaft rather than a separate engine. Thus, the Brabham BT46B was born, debuting at the Swedish Grand Prix in Anderstorp. During practice, the fan’s effect was so strong that the car was sucked down to the ground, forcing the team to replace the 1,000-pound springs with 3,000-pound ones to prevent the floor from scraping the track.

BRABHAM BT46B, Niki Lauda
Anderstorp, Swedish GP 1978

   To conceal the car’s superiority, the team sent it out with a full fuel load (210 liters) and the hardest available tires. Despite this, the BT46Bs qualified second and third. In the race, Lauda dominated and won effortlessly. After the event, nearly all the teams lodged protests with the FIA. Initially, a compromise was reached, allowing the fan to be used for three more races to give competitors time to adapt. However, following increased pressure, the decision was reversed, and the BT46B was banned immediately, though Lauda’s Swedish Grand Prix victory remained valid.

BRABHAM BT46B, Niki Lauda
Anderstorp, Swedish GP 1978

   The FIA’s official reasoning, backed by testimony from other drivers, was that the fan had the "side effect of lifting gravel and sand from the rear, creating a hazard for trailing cars and a clear safety risk for drivers." The BT46B remains unique in F1 history as the only car to compete in a single World Championship race, and win it.