Inspiration from racing: from Chaparral to McLaren
The basic idea of using fans to increase downforce originally comes from motor racing. Back in the 1960s, American racing pioneer Jim Hall used movable aerodynamic elements in his Chaparral racing cars. The Chaparral 2J from 1970 became particularly famous: two fans driven by a snowmobile engine sucked air out from under the vehicle, creating a vacuum that literally pressed the car onto the track.
This technology later made a brief but spectacular comeback in Formula 1 with Gordon Murray’s Brabham BT46B. Although the car complied with the rules, it withdrew from competition after just one win to avoid a costly development battle. Murray took up the concept again years later – first with the BMW-powered McLaren F1 and later with the T.50 hypercar. The latter generates up to 2200 pounds (around 998 kg) of downforce with a 7000 rpm fan.
The McMurtry Spéirling demonstrates an even more radical implementation: the all-electric 1000 hp vehicle uses fans to generate around 4400 pounds (1995 kg) of downforce even when stationary – more than twice its own weight. As a result, the car can allegedly even cling upside down to a ceiling.
BMW’s concept: jet technology instead of passive wings
BMW is going its own way with its current developments. Instead of relying solely on movable winglets or passive aerodynamic elements, the recently published patent provides for a complex nozzle system. A central fan unit draws in air, compresses it and directs it via a network of channels to adjustable nozzles on the motorcycle frame.
The nozzles could point in different directions:
- To the rear to aid acceleration.
- To the front to generate additional air resistance when braking.
- Upwards to generate downforce.
- To the side to provide additional thrust when cornering.
Switchable flaps within the duct system control where the air is directed – depending on the driving situation. In contrast to explosive gas generators, such as those tested by Bosch in 2018, BMW relies on a continuous flow of air. At that time, Bosch, a long-standing BMW partner, presented a type of “airbag nozzle drive” that could briefly counter-steer in the event of an imminent crash. The BMW technology, on the other hand, is designed to continuously stabilize handling and raise the traction limits – without one-off components.
Use in upcoming super sports cars expected
On May 24, 2025, BMW presented a concept motorcycle at the renowned Villa d’Este Concours that allegedly contains elements of this blow-aero technology – the BMW Concept RR. However, it is also conceivable that it could be used in future mid-range sports cars.
The system is apparently still in the testing and development phase, but BMW’s intensive patent activities and close collaboration with suppliers such as Bosch indicate that active aerodynamic systems could soon be a reality in motorcycle construction – and not just in the high-end segment.
