Why Do F1 Cars Spark?

November 17, 2023
Tom Thorns

Why Formula 1 cars spark is one of the most interesting questions I’ve seen online. And answering it requires me to delve into a bit of race history, aerodynamic forces, and human ingenuity.

In short, F1 cars are intended to produce sparks. It’s not a sign of damage nor is there anything wrong with the car.

Instead, the sparks are a result of an engineering “sleight of hand” that race teams engage in to take full advantage of the FIA regulations.

It all has to do with the plank on the floor of F1 cars and the titanium skids embedded in it that lead to sparks flying.

Let me explain!

The Wooden Plank Under an F1 Car

You see, under every F1 car, there is a wooden plank, which you can see below.

Now, you may be wondering why F1 cars have a wooden plank? We'll give a quick overview here, but see the main article for more in-depth coverage. This plank runs along the middle section of the car from front to end (almost). And on this wooden plank there are several titanium plates.

In short, the plank is a regulatory element imposed by the FIA to prevent race teams from abusing the “ground effect” by running the car too low to the ground. and  It forces the teams to use imposing the correct safe ride height for the car to keep the driver safe. If you didn’t know, the way F1 cars are built is strictly measured by the FIA, down to every minute detail.

Here are some of the official FIA regulations regarding the plank:

  • The thickness must be 10 mm, with a margin of error of 0.2mm
  • It must be uniform across and new
  • A minimum of 9mm is acceptable due to wear during the race
  • The metal skids can only replace parts of the plank and not go over the plank
  • The entire lower surface of the metal skids must be visible from below
  • The metal skids must be 15mm in thickness at a bare minimum
  • The metal skids must be made from titanium alloy

The logic is simple. If the plank under the car suffers damage beyond a certain threshold, that car is disqualified from the race. It means that the car had a lower ride height than allowed or abused the ground effect and ran so close to the ground that the plank was worn away too much.

This happened many times before, most notably with Jarno Trulli in the 2001 US Grand Prix. However, his team successfully appealed this decision by the FIA.

Michael Schumacher was also disqualified during the 1994 Belgian Grand Prix for the exact same reason – excessive plank wear.

Essentially, the plank forced teams to increase the car's height to avoid damaging it and risk disqualification. This led to lower car performance on the race track.

So, F1 teams thought of an ingenious workaround...

The Titanium Skid Blocks Embedded Into the Plank

Credit: Twitter.com

The FIA clearly states that the car will be disqualified if the wooden plank is damaged enough.

But they don’t mention anywhere that you can’t protect the plank. And that’s exactly what F1 teams did.

To protect this plank from being damaged, race teams began installing titanium skid blocks on it. When the car bottoms out, the plates will be damaged first instead of the plank.

It is these titanium plates that let F1 cars spark during races, which are especially glorious during night races. As the car bottoms-out, the plank and the skid blocks hit the track, which will create a light show of sparks.

This allowed F1 teams to lower the height of the race cars, thus increasing their performance on the track. Without the metallic skids, the plank wears quicker.

They could lower the height enough while accounting for:

  • The necessary damage to wear the titanium skid blocks during a race
  • The maximum damage to the plank permitted by the FIA technical regulations during a race

The plank is only damaged once the titanium wears itself enough. Essentially, it allows drivers to bypass the FIA’s regulations legally and enhance their performance on the track.

The FIA knows and allows it because there weren’t any downsides to it. The plank is still there, it just takes longer for it to receive any significant damage. If the damage incurred is within certain parameters, then it’s fine.

Either way, if a race car was too low to the ground, then not only would the titanium plate receive extensive damage but the plank would as well.

So, even if the team tried some shenanigans with the car design, it wouldn’t work. The time necessary to complete a race is more than enough to damage both the titanium plate and plank well beyond the safety limits.

When Do Sparks Fly in F1 Cars?

F1 cars don’t always spark during a race. It only happens during certain portions of the track. But why is that?

Let me explain when F1 cars spark:

During long straights

The most common situation when an F1 car begins sparking is when going down a long straight portion of the track. That’s when the car achieves higher speeds than usual because it doesn’t have to slow down for curvescorners.

The higher the speed of the car, the more downforce pushes down on it, resulting in the car being compressed into the ground.

This phenomenon is called “bottoming out”, when the floor of the race car makes contact with the track. And once that happens, you’ll see sparks fly out from the skid blocks.

During the start of the race

F1 cars spark when the race begins too, because the cars will have a full fuel tank (110kg of fuel), which increases their weight.

With a higher weight, they are more likely to make contact with the track surface due to the downforce. It also doesn’t take as much speed for a car to bottom out at the start of a race when it is heaviest.

While passing over bumps in the road

F1 tracks will often develop bumpy portions where the asphalt is slightly more elevated. This happens because of the enormous heat produced by the wheels tyres when gripping the asphalt.

When the asphalt becomes hot enough, it “moves around” because it becomes fluid, forming bumps.

And when F1 cars go over these bumps, they often leave behind sparks because the wooden planks underneath the cars makes contact with the asphalt.

Then, there are also tracks that are naturally bumpier than others, most notably the street circuits. These include the Montreal, Monaco, Singapore, Baku, and Melbourne tracks.

On elevated portions of the track

On tracks with elevation changes, sparks are more likely to appear for the same reasons outlined above. Some of these tracks include the Zandvoort, Imola, Sao Paolo, Suzuka, Austin, and Spa-Francorchamps tracks.

Considering how fast F1 cars move, it doesn’t take a big shift in track elevation to create sparks. Moreover, even if the shift in elevation is smooth, sparks will still appear because of the high speeds of the cars.

Is Sparking Dangerous for F1 Cars?

No, not at all. In fact, F1 cars are expected to produce spectacular sparks while driving down a track.

If they don’t, then that means something is wrong. One of two things:

  • The plank under the car has no titanium plates, so bottoming out will damage the plank, increasing the risk of disqualification
  • The car height does not correspond to the FIA regulations, so the plank does not touch the asphalt

All standard F1 cars spark at some point. That means they’re working as intended. The titanium plates are doing their job at protecting the plank on the floor.

Remember, the plank and the titanium plates, are there for safety reasons. They exist to ensure the driver’s safety and to avoid the abuse of the ground effect on race cars.

The only issue with sparks is that they might inconvenience other drivers by blinding them. In fact, Carlos Sainz, a driver for Ferrari, said that the sparking “looks great on TV, but for the drivers it is not pleasant at all,” after a race in Bahrain.

Imagine you’re driving behind someone and you’re looking to overtake them. But their car suddenly starts sparking and you can’t make any manoeuvres until you regain full visibility.

You might ask “could drivers do this on purpose to gain an advantage?”. Yes, they could. In fact, back in the late eighties, race driver Nigel Mansell would actively drive through bumps in the track to produce sparks that would blind and distract his competitors.

Credit: MotorSportRetro.com

This is one of the reasons why titanium skid blocks were initially eliminated in the 80’s and 90’s. But they were brought back in 2015 for more engagement and better dramatic effects during races, especially night races.

And the fact that it would prolong the lifespan of the wooden plank, like I mentioned previously.

All in all, the sparks you see coming from F1 cars is not dangerous nor unexpected. It’s the way these cars work.

Stay tuned for more Formula One guides!

Sources

  1. FIA – 2023 Formula 1 Technical Regulations
  2. The Race – Nine Lost F1 Wins that Stopped Schumacher Reaching 100
  3. The Sun – Why Do F1 Cars Spark?
  4. Motorsport Retro – Nigel Mansell: “I loved the skid plates and the sparks”