Ground-effect aerodynamics in Formula One were pioneered by Colin Chapman's Lotus team with the Lotus 78 and 79 cars, which used shaped sidepod tunnels sealed to the ground with flexible skirts to generate enormous downforce. When other teams, particularly smaller and less-funded British constructors, attempted to copy the concept, they often lacked the wind tunnel resources to refine their designs properly. The result was a generation of cars built as much by intuition as by detailed aerodynamic knowledge.
These cars were extremely pitch-sensitive. As the centre of aerodynamic pressure on the sidepod aerofoils shifted depending on the car's speed, attitude, and ride height, the forces interacted with the suspension in a feedback loop. At certain speeds the car would begin to resonate, rocking back and forth — particularly at lower speeds — sometimes quite violently. Some drivers reported symptoms similar to sea-sickness. The effect was compounded by the extremely stiff suspension setups these cars required to maintain a consistent ground clearance, making the oscillations even more unpleasant for the driver.
The root cause of porpoising lies in the sensitivity of underbody aerodynamic performance to ground clearance. As the car moves closer to the ground, downforce increases — but if the car moves too close, airflow under the car stalls, downforce drops suddenly, and the car rises. As it rises, flow reattaches, downforce returns, and the car is pulled back down again. This cycle repeats rapidly, causing the characteristic bouncing motion. Without sufficient aerodynamic data or simulation tools, teams could not predict or suppress this behaviour effectively.
The dangers of relying on extreme ground-effect downforce, combined with several severe accidents in 1982, led the FIA to mandate flat undersides on Formula One cars from 1983, effectively ending ground effect in the top category for four decades. However, Group C sportscars and other racing series that continued to use ground-effect aerodynamics suffered from porpoising until improved aerodynamic knowledge eventually allowed designers to minimise the problem through better floor profiling and suspension calibration.
Ground-effect aerodynamics returned to Formula One with the sweeping regulation changes introduced for the 2022 season, which mandated underbody tunnels in place of the front wings and bargeboards that had dominated car design for years. Porpoising re-emerged as an immediate and serious concern. At the first pre-season test in Barcelona ahead of the 2022 Formula One World Championship, George Russell warned that extreme porpoising could create safety issues. He later stated he was suffering from chest pain caused by porpoising during the 2022 Emilia Romagna Grand Prix.
At the 2022 Azerbaijan Grand Prix, Lewis Hamilton struggled to exit his car after the race as a result of the physical strain inflicted by sustained bouncing at high speed along the Baku street circuit's long straight. The episode drew significant attention from the FIA and prompted debate about technical solutions and whether interventions were needed to protect driver health, with some teams suffering far worse than others due to differences in floor designs and ride-height sensitivities.
Porpoising serves as a reminder that the interaction between aerodynamic downforce and suspension compliance is one of the most complex challenges in racing car design. The phenomenon has appeared in multiple eras of the sport whenever teams push ground-effect performance without sufficient understanding of the boundary conditions at which underbody flow stalls. The 2022 recurrence was ultimately brought under control as teams refined their floors and raised ride heights, but not before it had cast a shadow over the opening months of the new regulations era.
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