​FIA Issues New Technical Directive to Limit Porpoising

Anyone who watched the post race coverage of the Baku GP will have noticed Sir Lewis Hamilton having a seemingly difficult time exiting the cockpit of his AMG Petronas w13. The 7 time champion would go on to describe the race as the most painful and miserable experience he’s endured behind the wheel, noting significant back pain. 

This pain was caused by the phenomenon coined “porpoising”. This refers to the tendency of the ‘22 cars to bounce in high speed track sectors. This bouncing is caused by the “ground effect” principle dictated by the ‘22 technical directives. All cars on the grid use ground effect, and thus to some degree, all experience this phenomenon. 

Ground effect cars generate the majority of their downforce by exploiting airflow under the car. The floor designs of these cars feature fascinating and complex tunnels that accelerate the air beneath the car and creating a low pressure zone or near vacuum effect. This actually sucks the car closer to the ground. This was done to reduce the dirty air coming off of the heavy out-washing wings and appendages of the previous generation cars to allow for closer racing. Save for the tremendous speed of the ferrari and Red Bull camps, the new regulations have indeed closed the gap between the field and have created a compelling midfield battle. 

However, very few teams anticipated the porpoising phenomenon as it is difficult to simulate in a virtual environment or in the wind tunnel. Porpoising occurs when the ground effect works too well or too aggressively. The low pressure zone beneath the car can become so strong that it will stall itself out or cause the car to make physical contact with the ground. Contact with the ground or stalling of the low pressure zone will bounce the car upward until the low pressure zone can work again. On long straights the car will experience this hundreds of times making it quite difficult to drive. 

Some teams have been able to control this and reduce the effect on the driver and performance. However, as each team has designed their own car and pursued completely different design philosophies, one solution will not fit all. 

After continuous driver pleas, the fia has issued new technical directives to reduce the potential harm to drivers caused by porpoising.

The directive states that the skid plates beneath each car will be examined more closely to monitor wear and evidence of aggressive bottoming out. Secondly, the fia is working to develop a formula that will identify the allowed rate of oscillations experienced during porpoising. Porpoising will never completely vanish, it is baked into the basic design principle of these new cars. However, it will need to be controlled to prevent damage to the pilot. 

If a team is found to have significant damage to the skid plates or exceed the acceptable oscillation range, it stands to reason that they will be granted a penalty. 

One way to reduce the aggression of porpoising is to raise the ride height of the vehicle and stiffen the rear suspension to limit the squat resulting from the low pressure zone. This action will reduce the porpoising but it will also reduce the downforce and therefore overall performance of the vehicle. 

Until now teams have had to decide whether to pursue driver safety or performance. Mercedes namely was reluctant to raise the ride height of the vehicle as it would too greatly compromise performance. It appears that the FIA has forced the hands of teams to protect their drivers and accept the performance losses. 

A.F.