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F1 Skid Blocks Explained: What Are They For?

When watching a Formula 1 race you will likely have noticed sparks shooting out the back of the cars. This isn’t the cars taking damage, but instead the result of skid blocks that have been fixed to the underside of the car. This may leave some viewers wondering what exactly these skid blocks do.

Skid blocks are titanium plates that are fixed on to a plank on the bottom of F1 cars. These planks were made mandatory by the FIA after the high-profile death of Ayrton Senna in 1994. The planks are designed to stop cars from being too low to the ground, thus improving the safety of the drivers.

Drivers must make sure they don’t erode their plank on the underside of their car by more than 1mm throughout the race, otherwise they face disqualification. In this article we will discuss the role of skid blocks on the cars, as well as the reason they were implemented in the first place.

What Is The Plank On An F1 Car?

The plank on an F1 car is a long strip of laminate material that stretches from the back of the car to the area before the car’s front wing. The plank must be 30 centimeters in width and no less than a meter in length. It is fitted along the center of the car with no gap for air to pass through.

The planks do not restrict air flow around the bottom of the car, are fire-resistant, and identical on each car. This means teams cannot use a harder, more durable material to gain an advantage on their competition. Legality planks are checked by FIA stewards at the end of every race when the cars are in Parc Fermé condition to ensure that they have not worn away more than the legal 1mm amount.

The origin of the skid block can be traced back to the late 1980s and early 1990s, when F1 teams were manufacturing their cars to be as low to the ground as possible to gain more downforce and more speed. While this led to some incredible spark-filled battles between racers like Ayrton Senna and Nigel Mansell, it was beginning to become more and more dangerous for the drivers.

The full extent of this danger was realized at Imola in 1994, when both Roland Ratzenberger and the great Ayrton Senna were involved in fatal crashes, changing the way the world viewed the sport. This prompted a reaction from the FIA who then decided they needed to improve safety in F1 and introduced mandatory wooden planks to the bottom of the cars in order to monitor ride heights.

Cars that fell under the specified ride height face punishment. Michael Schumacher was found to have broken this rule at the 1994 Belgian Grand Prix when the rule was in its infancy. Jarno Trulli of the Jordan F1 team also fell foul of the rule in 2001, but his disqualification was overturned on appeal.

Are F1 Planks Made Of Real Wood?

F1 planks are not usually made of real wood. Early on, legality planks were made of a wood-based material called Jabroc. This consisted of dried beechwood and resin that were layered and pressed together. Currently, planks are usually made of a glass enforced plastic laminate.

As of their integration in 1994, legality planks were originally made of a wood-based material called Jabroc. Jabroc is made from kiln-dried beechwood and constructed in a layered composite style. Very thin strips of the beechwood are layered together with a very strong phenolic resin in between, before being pressed together to create the final product.

Each Jabroc plank had a consistent density and identical structure, meaning that they eroded at the same rate as each other, ensuring no unfair advantages. Jabroc is still used in other forms of motorsport, but the F1 plank has evolved since its beginnings.

Nowadays, planks on the underside of F1 cars are often made with a material called Permaglass, a glass enforced plastic laminate that is even lighter than its beechwood predecessor. As well as Permaglass, the planks contain aramid fibers, which are heat resistant and incredibly light and durable, so much so that they are also used for aerospace and military machinery.

What Is A Skid Block On An F1 Car?

Skid blocks on F1 cars are small plates made of titanium that are fixed on to the ‘legality plank’ attached to the bottom of the car. The plank is designed to stop cars from being too low to the ground. Drivers are disqualified if their legality plank is worn down too much during a race.

If the legality plank is worn down by more than a millimeter by the end of the race, the driver will be disqualified for having their car’s ride height too low. This is where the skid blocks come in. The idea of fitting a metal skid block is so they will take the force of the erosion before the plank, reducing the likelihood of a disqualification.

Some may see this as the exploitation of a loophole, but the skid blocks are FIA certified, making them a totally legal addition to the car. The skid blocks are arranged in a very specific order on the plank, designed to make sure they make contact with the track rather than the wooden plank.

Why Do F1 Cars Have Skid Plates?

F1 cars have skid plates to protect the underside of the car when they go over bumps and kerbs on the track. Skid plates, sometimes called skid blocks, are usually made of titanium and are the reasons F1 cars spark, and these skid blocks are attached to the legality plank on the car’s floor.

F1 teams started to fit skid plates, originally made of hard metals, on to their cars so that they would take the brunt of the friction when going over the track, reducing the chance of losing vital driver and constructors’ points. With the miniscule number of cases where the ride height rules have been broken, the decision to fit the plates has proven to be a successful one.

What Are Modern F1 Skid Blocks Made Of?

Modern F1 skid blocks are made of titanium. Titanium replaced tungsten as the skid block material in 2015. Tungsten would fragment upon excessive wear, leaving debris on the track. Titanium is lighter, has better impact strength, and is safer than tungsten, and so has been used since.

F1 skid blocks have been through multiple stages of evolution since they first came on to the F1 scene. Originally, skid blocks were made from harder metals like tungsten, which were heavy and had a slower rate of wear. The problem with using harder metals is that when they do start to wear, they fragment, sending small chunks of metal along the surface of the track.

This fragmentation caused punctures and other dangerous situations for drivers, forcing the FIA to request that skid blocks be made of titanium as of 2015. Titanium is lighter than tungsten and is less durable with a quicker wear rate. But while it may not be as strong, it doesn’t wear in a dangerous way, making it a far more favorable material for skid plates.

Why Do The Skid Blocks Create Sparks?

As titanium is a non-ferrous metal, meaning it contains little to no iron, the updated skid blocks announced the return of the bright, white sparks to Formula 1 in 2015, leaving a positive fan reaction. The sparks are the result of friction between titanium and tarmac. Sparks mainly occur on straights, due to the strong downforce created by speeds over 200 mph pushing the cars closer to the track.

Final Thoughts

Skid blocks and planks in F1 are used to ensure that cars meet the legal ride height and are constantly redesigned to improve safety and speed. They are now safer than they have ever been and have reduced the severity of crashes in F1, while also satisfying fans with the reintroduction of sparks.