Why Do Sparks Come Out Of F1 Cars?

F1 cars generate sparks due to titanium skid blocks embedded in the “legality plank” on the underside of the vehicle. At high speeds, aerodynamic downforce pushes the car towards the track, causing the skid blocks to make contact with the surface. This contact creates friction, especially on circuits with uneven kerbs or bumps, resulting in visible sparks as the titanium scrapes along the ground.

It’s important to note that the titanium skid blocks were reintroduced deliberately in 2015 for aesthetic purposes. The sparks had largely disappeared due to design changes in the 1990s, but the FIA decided to mandate the use of titanium to bring them back. As former FIA Race Director Charlie Whiting explained at the time, “We were keen to reintroduce them as they look spectacular, especially at night.”

Why do F1 cars spark? 

As F1 cars reach incredible speeds, the aerodynamic downforce increases proportionally, forcing the vehicle closer to the track surface. When the downforce becomes substantial enough, it causes the underside of the car to compress against the circuit, a phenomenon known as “bottoming out.” It’s at this moment, when the car’s floor kisses the tarmac, that the titanium skid blocks make contact, igniting a dazzling display of sparks that trail behind the speeding car.

Titanium skids were used previously in the ’80s and ’90s. To distract the drivers behind him, Nigel Mansell used to find bumps on the track to generate sparks. Titanium skids were reintroduced in 2015 for both safety reasons (titanium is lighter than tungsten) and to improve the show. 

The low ride height and stiff suspension of modern F1 cars also contribute to the sparks. As Mercedes AMG F1 Chief Engineer Andrew Shovlin noted, “The cars are running very close to the ground, and the stiff suspension means that any bumps or undulations in the track surface can cause the car to hit the ground, producing sparks.”

Charlie Whiting further explained “the plank is the long bit of wood, the skids are bits of metal within the plan. The skids have formerly been made of a heavy metal, which has been very resistant to wear, and they put the skids around the points in the plank where thickness is measured. Planks have to start off at nominally 10mm thick and they can’t be less than 9mm thick. However, we only measure them around certain holes in the plank. So they position the skids around those holes.

“This metal is extremely heavy and when pieces detach they can be extremely harmful. We saw two punctures in Spa previously because of bits of this metal that lay in a kerb and caused damage. In a worst case scenario they could fly off and hit someone.

“The purpose of making them out of titanium is threefold: Firstly, it’s safer, because if they do come off they are about a third of the weight of the existing ones.

“Secondly, the titanium wears some 2-2.5 times more quickly than the metal currently used. Thus cars will have to be run a little bit higher to manage wear and teams won’t be able to drag them on the ground quite as much as they have in the past.

“The third effect is that you will see a lot more sparks, which some people think will look a little more spectacular”.

The titanium skid blocks are mounted on the rear crash structure, positioned behind the gearbox. Former Ferrari Team Principal Mattia Binotto shed light on this, stating, “The skid blocks are strategically placed to protect the car’s floor and diffuser, while also creating the sparks that have become an iconic part of modern F1.”

Titanium skids and the FIA Technical Regulations

The skids are defined in the FIA Technical Regulations…

3.7.11 Skids

The lower surface of the plank may be fitted with flush-mounted metal skids which:

a) May only be fitted in place of plank material.

b) Have a total area no greater than 20000mm² when viewed from directly beneath the car.

c) Are no greater than 4000mm² in area individually when viewed from directly beneath the car.

d) Are fitted in order that their entire lower surfaces are visible from directly beneath the car.

e) Must have a minimum cross-sectional thickness of 15mm across its external boundaries in plan view. The minimum wall thickness between an internal fixing hole and the external boundaries of the skid must be no less than 7.5mm.

f) Must have an upper surface no more than 3mm below the reference plane.

g) Must be designed such that they are secured to the car using the fasteners described in Article 3.7.12 and that, when viewed from directly beneath the car, no part of the skid is more than 50mm from the centre line of a fastener which passes through that skid.

h) Must be made from Titanium alloy.