Formula One Brake Systems

Braking is the first element in a Formula One car’s cornering phase. If the car isn’t slowed down at the right point and with the right pressure on the pedal, it will compromise the remaining phases – hitting the apex, taking the right line, carrying the optimum speed through the corner, getting the power down on exit and completing a clean run to the next turn. This can have a major impact on a driver’s lap time. 

Similar to a road car, the brakes on a Formula One car work on all four wheels. So how exactly does the system work? When the driver steps on the brake pedal, it compresses two master brake cylinders – one for the front wheels and one for the rear – which generate fluid pressure. At the front, the system is very straightforward.

The fluid pressure is delivered directly to the front brake callipers. Inside each calliper, six pistons clamp pads against the disc – and it is this friction that slows the car down. At the rear, things are a lot more complex… 

At the rear, the wheels can be decelerated by three separate sources: friction from the brakes, resistance from the spinning engine – so called “engine braking” – and finally, electrical braking that results from harvesting energy by the hybrid electric motor – the MGU-K (Motor Generator Unit – Kinetic).

Although the driver can adjust each of these effects independently on his steering wheel, when he presses the brake pedal, the three systems act in concert via the Brake By Wire (BBW) system to provide the driver the overall retardation he has requested.

When the driver presses the pedal, the fluid pressure he generates in the rear braking circuit is picked up by an electronic pressure sensor. The signal from this sensor represents the overall rear braking demand from the driver and is passed to the Electronic Control Unit (ECU) where it is turned into a series of commands to brake the rear of the car.

The harder the driver presses, the larger the signal; the larger the signal the more aggressively the ECU will send out demands to the three rear systems (the brake callipers, the engine braking and the MGU-K) to provide the retardation requested.

The ECU distributes its efforts to the three systems according to the manner that the team has set up the car, modified by the way that the driver has adjusted the switch settings on the steering wheel. 

Compared with the front, at first glance, the rear system looks byzantine in its complexity. Why would we ever want to use a hydraulic master cylinder to generate pressure to be picked up by a pressure sensor simply to generate an electronic demand signal to an ECU?

Why would we not do it much more simply by measuring the position of the brake pedal to get an electronic demand signal?

Why would we ever want to have a rear braking system that arbitrates between three separate systems when we could simply use conventional brakes like a normal car?

The answers to these questions fall in two camps: safety and performance. Once you have committed to using a Brake By Wire system to control the rear braking, you need to ensure that there is a safe backup in the event that the system fails.

This is why teams go to all the trouble of using the driver’s pedal action to produce hydraulic pressure in a brake line. If the BBW system ever fails (and there is a set of sensors and a computer routine continuously devoted to checking its integrity), then it is immediately bypassed, and the pressure generated by the driver’s foot is passed directly to the rear brake callipers just like in a normal car.

If you spend any time with a driver listening to them talk about the car, one of the most common terms you will hear them refer to is “braking stability”.

Drivers, of course, want brakes that have good “bite” (sharp initial deceleration when they stamp on the pedal), they want strong deceleration without any “fade” (more of this later), they want good “feel” (a sort of predictable response, push harder = stop more, push less = stop less), but above all, they want good braking stability.

Unlike bite, fade and feel, something that all drivers will be able to relate to, it is much harder to understand what a driver means when they talk about “braking stability”. This is because we do not use brakes in the way that racing drivers use brakes. When we use the brakes in a road car, we are generally pointed in a straight line, and we rarely push them hard enough to make the tyres come close to activating the anti-lock brake system.

Racing drivers operate in a very different place. Every time they press the brakes they want to slow down as rapidly as the car will permit them. This means that they push the brakes right up to the point where the tyres will lock up – every corner, every lap.

Furthermore, they don’t only press the brakes when the car is in a straight line. They push them from the end of the straight, they keep pushing them as they are turning in, and they only finally come off the brakes right at the apex of the corner, an instant before they start to apply the power for the exit of the corner.

Throughout this entire time, the brakes are almost as important as the steering wheel for controlling the direction that the car is pointed. During this manoeuvre, if things are going well for the driver, then the car is held with all four wheels right at the very limit of skidding but without the car deviating from the driving line that the driver wants to follow through the corner.

If things are going slightly less well, then the front wheels might start to slide a little more than the rear wheels, giving the driver a lazy, understeering car that will not turn.

If things are going less well still, then it might be the rear wheels that slide more than the front wheels, and if they slide too much, then the car will start to spin. 

For this reason, the driver cares enormously how much braking happens on the front wheels compared to the rear wheels. If the car is unstable, and wanting to spin on corner entry, then you probably need to ask less of the rear brakes, and more of the front.

If the car is lazy and understeery, then you would do the opposite. 

Furthermore, as the corner progresses from initial braking to turn-in to corner apex, the driver wants different things. As the car starts to turn in, the car can often have a natural tendency to oversteer which is progressively replaced by understeer as the apex approaches.

This tendency can be counteracted to some extent by a clever braking system which would ask less of the rear brakes on turn in (to stabilize the car) and then ask progressively more of the rear brakes (compared to the front) as the apex approaches.

This clever process is called Brake Migration – a dynamic change of the brake balance as a function of the brake pressure. It is this cleverness that the Brake By Wire system provides.

Guided by the rotary switch settings that the driver has made on their steering wheel, the BBW system juggles the braking input of the three main actuators (the callipers, the engine and the MGU-K) to provide the driver with a smooth, predictable shape to the rear braking action that allows him to keep the car at limit of adhesion (without any anti-lock brakes) while steering the car through the braking phase of the corner. 

A lot of force. The drivers really have to stamp on the brakes with every application, almost standing up in the car to do so.

On road cars, servo-assisted brake systems multiply the pressure you apply to the master cylinder but the regulations in Formula One demand that the braking force has to be generated by the driver alone.

They need very strong legs to do this, but they do get some help from the violence of the braking manoeuvre itself. The cars decelerate at around 5G (compared to the 1G we might see during an emergency brake in our road cars).

At this deceleration, their leg will weigh approximately 100kg, and the weight of their leg on the brake pedal provides its own form of servo-assistance to help them – the harder they press, the more the car slows, the more it slows, the more their leg weighs which helps them to press harder.

What is remarkable is that in the midst of all this, while pressing the pedal with well over 100kg of force, the driver is required to modulate his effort on the pedal with all the delicacy of a concert pianist in order to coax the car through the corner at the very limit of what the tyres will permit – it is a delightful contrast of violence and gentleness 

The perfect spot to hit the brakes in an F1 car will depend on a lot of variables – fuel loads, tyre compound, the amount of degradation on the tyre and the levels of management a driver is doing.

Therefore, in the race, this will constantly be shifting, as fuel burns off and tyres wear down, with drivers having to be reactive. Qualifying is less variable owing to similar fuel loads and fresh tyres, meaning the braking points remain largely the same.

Drivers ramp up the braking as the weekend goes on, using practice to really find the limit. They’ll start off conservatively, before pushing deeper and deeper into the corner until they find the right marker to begin applying the brake pedal.

Undoubtedly the trickiest moment of the weekend is braking for the first corner on lap one.

First, drivers don’t receive a whole lot of opportunity to drive on track on Sunday before the race begins. This means that drivers have to base the crucial decision of when to brake into Turn 1 on a rough estimate of the day’s grip levels which they form on the laps to grid and the formation lap.

Second, despite the usual weaving to warm the tyres on the formation lap and the fact that tyre blankets are fitted to the car as long as possible, brakes and tyres are still not at the optimal temperatures at the start of the race, making it harder to judge just how much stopping potential they’ll provide.

Finally, the field is bunched up at the start of the race, with all cars vying for the same patch of track.

So, drivers need to react to many different elements – making sure they get into the right slipstream, predicting what rivals will be doing, estimating grip levels, ensuring they don’t brake too early and lose positions, but also taking any opportunity to gain places. 

Very hot, is the simple answer. Maximum temperatures for the brake discs can reach 1,000°C or more. The carbon discs can easily handle these individual peak temperatures; however, high temperatures over a prolonged period can create some issues.

Cooling mainly takes place on straights, when the car is travelling at high speeds, allowing for a lot of air to pass through the brake ducts.

On a track like Monaco, for example, cooling the brakes can become a real problem despite the relatively low speeds as there are a lot of corners and thus a lot of braking with only very short straights in between. 

The brakes need air passing through the brake ducts and out through the uprights to cool them down. There are over 1,000 holes drilled into the sides of the brake disc to maximise the surface area and therefore the cooling potential. While those holes help to drop the temperatures significantly when the car is going down the straight, they also mean that the discs reach higher temperatures because the thermal mass of the disc is lower.

The issue with a brake disc that is too hot is that you experience a phenomenon known as ‘fade’. Fade means that there is not enough mutual friction between the pads and discs, rendering the brakes much less effective to slow the car.

And it’s not just the brake performance that suffers from high brake temperatures: the dispersed heat from the brakes also needs to be managed, as it exits around the wheels and tyres, which work in their own temperature windows to achieve peak performance.

The brake duct brings in air to cool the temperatures down, but this also impacts aerodynamic performance. The bigger the air duct, the worse the impact on aero performance, but the more cooling that is gained.

So, a balance must be found in order to provide the right level of cooling while also not negatively impacting the aerodynamic flow around the brakes.

The brakes can run as low as 200°C. If the brakes are too cold, there isn’t enough bite or initial grip to slow the car down. So, temperature management is a decisive factor in the performance of the brakes on an F1 car and getting them in the right window is crucial.

This is particularly tough at key points in the race weekend like the race start or a Safety Car restart. F1 drivers will therefore oftentimes swerve around when they follow the Safety Car or press the BW (“Brake Warming”) button on their steering wheels which lets them override the brake balance.

F1 circuits can pose challenges for different reasons when it comes to braking. Somewhere like Baku features a lot of twisty, lengthy sections of corners, where speeds are relatively low. So, the brakes can’t be cooled as much. The long start/finish straight provides a welcome chance for the brakes to reduce in temperature, but they are then potentially too cold for the heavy stop of Turn 1.

Monaco is tough owing to the fact the car speeds are so low, therefore less air is going through the ducts to cool the brakes down. It’s also a relentless track for corners, with very few straights. So, brakes can get very hot.

Somewhere like Canada also punishes the brakes, as there are continuous long straights and heavy stops, which puts the braking system through its paces and can lead to higher wear rates or higher temperatures than at other circuits. 

Lock-ups are a relatively common phenomenon in Formula One. They happen when too much force is applied to the brakes, causing the disc to stop or rotate slower than the car’s motion. The tyre then scrubs along the surface of the track, sometimes creating white smoke.

While you can see this happen relatively often in F1, lock-ups have become very rare in the road car world. There are two reasons for that. Aerodynamics play a major role in Formula One and means that the faster an F1 car goes, the more downforce it creates.

When the downforce increases, so does the grip level – which means that the cars have more stopping potential at high speeds than they have at low speeds. This also means that the grip level constantly changes while the car is slowing down.

It would be relatively difficult to lock the wheels when the car is going 300 km/h; however, it is much easier to do at speeds below 100 km/h.

Drivers therefore typically hit the brake pedal harder when entering a braking zone as this is when the car has its maximum stopping potential, before easing off as they get towards the turning phase to try and avoid a lock-up.

But there’s another reason why F1 cars lock up more often than road cars: modern road cars are all equipped with anti-lock braking systems (ABS); however, the regulations in F1 don’t permit ABS.

F1 drivers brake without ABS by using a combination of heel-toe downshifting and threshold braking techniques.

Heel-toe downshifting involves pressing the brake pedal with the right foot while blipping the throttle with the right heel to match the engine and transmission speed when downshifting.

Threshold braking is a technique where the driver applies maximum braking force without locking up the wheels. This requires the driver to have a good feel for the brake pedal and the ability to modulate braking force precisely.

F1 drivers practice these techniques extensively to develop the necessary skills to brake without ABS and to maximize their braking performance.

F1 drivers avoid locking their brakes by using a combination of techniques, including brake balance adjustment, tire pressure management, and precise braking modulation.

Brake balance adjustment involves changing the distribution of braking force between the front and rear wheels to optimize braking performance and prevent lock-ups.

Tire pressure management is also critical, as F1 drivers need to ensure that their tires are at the optimal temperature and pressure to provide maximum grip and prevent lock-ups.

Finally, precise braking modulation is essential to prevent lock-ups, as F1 drivers need to apply the right amount of braking force at the right time to slow down the car without locking up the wheels.

These techniques require extensive practice and experience to master, and F1 drivers spend a lot of time fine-tuning their braking performance to minimize the risk of lock-ups.

Yes, F1 cars have brake fluid. The brake system in an F1 car is hydraulic and uses brake fluid to transmit the force from the brake pedal to the brake calipers, which then apply pressure to the brake pads and slow down the car

F1 cars use Endless RF-650 brake fluid. This brake fluid has a dry boiling point of 323 degrees Celsius and a wet boiling point of 218 degrees Celsius.

Endless RF-650 brake fluid is a high-performance brake fluid that is specifically designed for racing applications, including F1.

It has a high boiling point, which means it can withstand the extreme heat generated by the brakes of an F1 car during a race.

The dry boiling point of the fluid is 323 degrees Celsius, which means it can withstand heat up to this temperature without boiling.

The wet boiling point of the fluid is 218 degrees Celsius, which means it can withstand heat up to this temperature even when it has absorbed some moisture.

This makes it ideal for racing where the brakes are often subjected to high temperatures and moisture. 

F1 brakes cost around $80,000. This cost doesn’t include the price of replacing sets of brake discs and brake calipers throughout a season, which can cause the expenses to gradually increase over time. As brakes are one of the most essential parts of a car, they have to be maintained well.

F1 brakes last for about 500 miles. In practice, a new pair of brake discs and pads will be bedded in during the first practice session, then removed and reused as the qualifying or race brakes. Meanwhile, a used set will be fitted for the rest of free practice, which gives the parts a life of just 500 miles. This means that F1 teams have to replace the brake discs and pads frequently throughout the season to ensure that they are always in good condition.

F1 brakes can catch fire when stopped due to a phenomenon called “heat soak”.

When an F1 car is stopped, the brakes no longer receive airflow to cool them down, and the heat generated by the brakes can build up and radiate to the surrounding components.

The high temperatures can cause the brake dust and other debris to ignite, resulting in flames. This is more likely to happen when the brakes are already very hot, such as after a long stint of hard braking during a race.

F1 teams take steps to prevent brake fires, such as using heat-resistant materials and designing the brake ducts to provide adequate cooling. However, brake fires can still occur, especially in extreme conditions.

The hardest braking zone in F1 is Turn 8 at Abu Dhabi. This is a tight left-hander at the end of the long back straight, which requires drivers to drop from 204 to 44mph in the space of just 1.6 seconds. The braking force experienced by the drivers during this maneuver is around 5.2G, which is equivalent to the force felt by a fighter pilot during a high-speed turn.

F1 brakes are made of carbon fiber composite materials.

The brake discs are made of carbon-carbon composite, which consists of a matrix of carbon fibers and a carbon-based resin.

This material is extremely lightweight and has excellent thermal conductivity, which means it can absorb and dissipate heat quickly.

The brake pads are also made of carbon composite, which is designed to provide high friction and wear resistance while generating less dust than traditional brake pad materials.

F1 teams use a variety of suppliers for their brake components, including Brembo and Carbon Industrie.

Formula One cars are equipped with highly specialized braking systems, distinct from those found in standard vehicles. These systems are a critical component in the performance and safety of the cars, allowing them to decelerate rapidly from high speeds during races.

Material Composition: The brake discs and pads in F1 cars are made from a carbon fiber composite. This material choice is due to its ability to withstand the extreme heat generated during braking – temperatures can soar to 1,000°C. Carbon fiber composites offer excellent thermal conductivity, which helps in managing these high temperatures effectively.

Brake By Wire (BBW) System: The rear brakes of an F1 car incorporate a sophisticated electronic system known as Brake By Wire. This system works in conjunction with traditional mechanical braking, engine braking, and energy recovery systems to provide precise control over the car’s deceleration. The BBW system allows for adjustments in braking force distribution between the front and rear wheels, adapting to different racing conditions and driver preferences.

Cooling Mechanisms: Given the intense heat generated by the brakes, F1 cars employ advanced cooling solutions to prevent performance degradation. Brake ducts channel air to the brakes, while the design and materials used in the brake discs themselves help dissipate heat. This cooling is vital for maintaining the integrity of the brake system throughout a race.

These components and systems together form the backbone of an F1 car’s braking capability, enabling drivers to navigate tracks with confidence and precision. The design and technology behind these brakes are a testament to the innovation and engineering excellence that Formula One represents.

Yes, Formula One teams frequently choose Brembo as their provider for braking systems. Brembo, a leader in the development and production of high-performance brake systems, has a long-standing association with the sport. Their products are renowned for their reliability and performance, making them a preferred choice among many teams.

Partnership and Innovation: Brembo’s involvement in Formula One is marked by a commitment to innovation and development. The company works closely with teams to supply brakes that meet the demanding requirements of F1 racing. This partnership extends beyond supplying parts; it involves continuous research and development to push the boundaries of what’s possible in brake technology.

Customization and Support: Brembo provides teams with brakes that are not just off-the-shelf but are developed in close collaboration with each team to meet their specific needs. This customization ensures that the brakes integrate seamlessly with the unique characteristics of each car, optimizing performance. Additionally, Brembo offers comprehensive support to teams, ensuring that the brakes perform reliably throughout the racing season.

Technological Excellence: The choice of Brembo by F1 teams underscores the company’s technological excellence. Brembo’s brakes are designed to withstand the extreme conditions of F1 racing, from the high temperatures generated during braking to the need for rapid deceleration. Their carbon fiber composite brake discs and pads set the standard for performance, durability, and heat resistance in the sport.

Brembo’s presence in Formula One highlights their status as a key player in the development of advanced braking systems. Their commitment to excellence and innovation ensures that F1 cars are equipped with brakes that offer superior performance, reliability, and safety.

No, Formula One teams do not change brakes after every race as a standard practice. The durability and performance of F1 brake systems, particularly those made from carbon fiber composites, allow them to last for several races under normal conditions. However, the frequency of brake changes depends on a variety of factors including the track layout, braking demands of specific circuits, and the wear and tear experienced during races and practice sessions.

Track Demands: Circuits with heavy braking zones, like Monza or Montreal, place greater stress on the braking system, potentially leading to increased wear. In contrast, tracks with fewer hard braking points may result in less wear, allowing brake components to last longer.

Wear and Performance Monitoring: Teams closely monitor the condition and performance of brake components throughout race weekends. Advanced sensors and data analysis tools help engineers assess wear levels and make informed decisions about when to replace parts. This ensures that the cars always have optimal braking performance without unnecessary changes.

Regulations and Strategy: FIA regulations and team strategies also influence decisions on brake changes. Teams must balance the need for peak performance with the desire to avoid penalties for exceeding component usage limits. Strategic considerations, such as the timing of brake changes to coincide with other car maintenance activities, also play a role.

While F1 brakes are built to withstand extreme conditions and do not require replacement after every race, teams make strategic decisions on when to change them based on track demands, wear levels, and regulatory considerations. This approach ensures that the cars maintain high performance while adhering to the sport’s regulations.

Formula One cars utilize regenerative braking through a sophisticated system known as the Energy Recovery System (ERS). This system captures kinetic energy that would otherwise be lost during braking and converts it into electrical energy, which can be stored and later used to provide additional power to the car. The ERS is a key component of the hybrid power units used in modern F1 cars, contributing to their efficiency and performance.

Components of ERS: The ERS comprises two main elements: the MGU-K (Motor Generator Unit – Kinetic) and the MGU-H (Motor Generator Unit – Heat). The MGU-K is directly involved in regenerative braking. It functions by converting the car’s kinetic energy into electrical energy during deceleration, which is then stored in the car’s energy storage system, typically a lithium-ion battery.

Operation During Braking: When an F1 driver applies the brakes, the MGU-K goes into action. Instead of the brake pads converting all the kinetic energy into heat through friction (as happens in conventional braking systems), the MGU-K captures a portion of this kinetic energy and converts it into electrical energy. This process reduces the load on the physical brake components, contributing to their longevity and reducing wear.

Boosting Performance: The stored electrical energy can be strategically deployed by the driver to boost the car’s performance on the track. This is particularly useful for overtaking maneuvers or defending a position, as it provides a temporary increase in power output from the car’s power unit.

Efficiency and Strategy: The use of regenerative braking in F1 not only enhances the efficiency of the cars by recovering energy that would otherwise be wasted but also adds a strategic element to racing. Teams and drivers must carefully manage the use of the stored energy, deciding when to deploy it for maximum competitive advantage.

Regenerative braking in Formula One, facilitated by the ERS, represents a fusion of advanced engineering and strategic racing. It showcases the sport’s commitment to innovation, efficiency, and sustainability, while also adding depth to the racing strategies employed by teams and drivers.

Yes, modern Formula One cars incorporate “fly-by-wire” technology in several aspects of their operation, most notably in their throttle and braking systems. This technology replaces traditional mechanical linkages with electronic systems, allowing for more precise control, quicker response times, and enhanced functionality.

Throttle System: In the context of the throttle, fly-by-wire means that the driver’s input on the accelerator pedal is converted into electronic signals. These signals are then processed by the car’s computer to adjust the engine’s power output accordingly. This system allows for very precise control over the car’s acceleration and enables the integration of complex engine management strategies, such as traction control and fuel efficiency improvements.

Brake-By-Wire (BBW) System: The braking system in Formula One has also adopted fly-by-wire technology, particularly at the rear of the car. The Brake-By-Wire system works in conjunction with the Energy Recovery System (ERS) to manage braking force and the regeneration of energy. This system allows for precise control over the braking process, optimizing the balance between mechanical braking and energy recovery. It also helps in managing the distribution of braking force between the front and rear wheels, enhancing the car’s stability and handling during deceleration.

Steering and Gearbox: While not traditionally referred to as fly-by-wire, the steering and gearbox operations in F1 cars are also heavily electronic. The steering system, though still mechanically linked, includes electronic assists and adjustments that can be made on the fly. Similarly, gear shifting is electronically controlled, with drivers using paddles behind the steering wheel to change gears, and the car’s computer system managing the gearbox mechanics.

The adoption of fly-by-wire technology in Formula One reflects the sport’s cutting-edge approach to automotive engineering. It allows for greater integration of electronic controls and driver aids, improving performance, safety, and the overall driving experience. However, it also requires teams to have a high level of technical expertise to optimize these systems for competitive advantage.

Formula One drivers determine when to brake based on a combination of pre-race preparation, experience, and real-time feedback during the race. The process is highly sophisticated, involving both the driver’s skill and the use of advanced technology.

Pre-Race Preparation: Before a race, drivers spend hours studying the track, including simulators and telemetry data, to memorize braking points for each corner. These braking points are specific locations on the track where drivers must begin to brake to navigate a turn effectively. Preparation also involves discussions with engineers about the car’s setup and strategy, which can influence braking behavior.

Visual Markers: During the race, drivers use visual markers on the side of the track, such as signs, kerbs, or changes in the track surface, as cues for when to brake. These markers are identified during practice sessions and are crucial for timing braking accurately, especially at high speeds.

Experience and Instinct: A driver’s experience plays a significant role in knowing when to brake. Over time, drivers develop an instinct for the car’s behavior and how it responds to braking at different speeds and track conditions. This instinct, combined with a deep understanding of the car’s capabilities, allows drivers to make split-second decisions about when to brake.

Real-Time Feedback: Drivers receive real-time feedback from the car’s instrumentation, such as speedometers and gear indicators, which helps them judge their approach to corners. Additionally, the team can communicate with the driver via radio, providing information about track conditions, tire wear, and other factors that might affect braking.

Adaptation to Conditions: Drivers must constantly adapt their braking points based on the race conditions. Factors such as tire degradation, fuel load, weather conditions, and traffic on the track can all necessitate adjustments to when and how hard to brake.

Physical Sensations: The physical sensations of acceleration, deceleration, and the car’s behavior provide immediate feedback to the driver. Skilled drivers can feel when the car is on the limit of grip, allowing them to optimize braking and cornering performance.

Knowing when to brake in Formula One is a complex skill that combines detailed preparation, visual cues, experience, real-time feedback, and adaptation to evolving race conditions. It’s a testament to the drivers’ skills and their deep understanding of their cars and the tracks they race on.