Racing | Formula 1 | 1978 Swedish Grand Prix — Lauda Wins in the Brabham BT46B Fan Car

On 17 June 1978, two Brabham-Alfa Romeo cars appeared on the Scandinavian Raceway grid with large fans mounted at their tails, making the IX Swedish Grand Prix a test of both engineering and the rulebook.

The BT46B's rear fan drew cooling air through the car while also reducing air pressure beneath its skirted floor to increase grip, a response to the ground-effect advantage demonstrated by the Lotus 79.

Rival entrants protested that the fan was a moving aerodynamic device, but the pre-race protest was rejected and both Brabhams were allowed to start.

Mario Andretti put his Lotus-Ford on pole in 1 minute 22.058 seconds, with John Watson's Brabham second and Niki Lauda's number 1 BT46B third in 1 minute 22.783 seconds.

Andretti led the opening phase, but Lauda stayed close and moved ahead on lap 38 after the Lotus driver made an error; Andretti retired on lap 47, leaving the Austrian clear at the front.

Lauda completed 70 laps in 1 hour 41 minutes 0.606 seconds and set the official fastest lap on lap 33 in 1 minute 24.836 seconds.

Riccardo Patrese finished second for Arrows-Ford, 34.019 seconds behind, while Ronnie Peterson placed third for Lotus-Ford at 34.105 seconds; the Formula 1 archive and independent classification agree, and no later penalty changed the podium.

This was the BT46B's only Formula One World Championship race, so its competition record became one start and one victory, although Brabham continued the season with other BT46 variants.

The place is part of the engineering story: the 1978 event used Scandinavian Raceway's newly revised 4.031-kilometre layout, whose long Flight Straight also served as an airfield runway and whose pit lane sat away from the start-and-finish line.

The accompanying image is a diagram of the 1978–1997 Anderstorp configuration, not a photograph of the race or the BT46B.

Sources: Formula 1, “1978 Swedish Grand Prix — Race Result” (https://www.formula1.com/en/results/1978/races/398/sweden/race-result), “Starting Grid” (https://www.formula1.com/en/results/1978/races/398/sweden/starting-grid), and “Fastest Laps” (https://www.formula1.com/en/results/1978/races/398/sweden/fastest-laps); Motor Sport, “1978 Swedish Grand Prix” (https://www.motorsportmagazine.com/database/races/1978-swedish-grand-prix/); Grandprix.com, “Swedish GP, 1978” (https://www.grandprix.com/races/swedish-gp-1978.html).

Image: Cherkash, CC BY-SA 4.0, via Wikimedia Commons; a white-background derivative is used without changing the depicted layout (https://commons.wikimedia.org/wiki/File:Scandinavian_Raceway_1978.svg).