McLaren’s extra brake pedal that disrupted Formula 1

McLaren’s ingenious little secret that won them several F1 Grand Prix

McLaren are known to be innovators. Just look at their production cars and you’ll soon find several interesting technologies and examples of ‘outside-the-box thinking’ that separate them from their competitors.

For instance, the 600 LT features top mount exhausts which are only found in a handful of other cars. They weigh less, are cooled more effectively and also minimise aero disturbance.

The McLaren F1 from the 90s was the first all-carbon-fibre supercar and weighed just 1,138 kg which is still lighter than most of today’s supercars. It was also the fastest car in the world for a whopping 11 years and is still the fastest naturally aspirated car in the world today, over 25 years after its release.

These are just some examples of McLaren’s industry-leading genius that not only let them create interesting and very attractive supercars, but have also allowed them to become the second most successful Formula 1 team in history, second to Ferrari, of course. The ridiculously simple extra brake pedal allowed drivers Hakkinen and Coulthard to gain almost half a second per lap, which in Formula One terms, is a huge leap.

From a bathtime realisation to a race-winning technology

In 1998, McLaren’s sneaky extra brake pedal was banned in F1 racing, mainly because it was an innovation that was too advanced for the competition to handle. It all started as a Eureka moment that came to McLaren’s chief engineer, Steve Nichols, while he was laying in the bath at his parents’ house, just as Archimedes was when he coined the term ‘Eureka’!

Nichols was thinking about how the cars were set up to have a lot of understeer with thick front tyres and thin rear tyres. To counteract the understeer, Nichols thought about the possibility of using the rear brakes during corners.

Nichols recalls how he talked to Paddy Lowe, head of R&D at the time, about the possibility of an extra brake pedal to operate a rear brake on one side of the car.

“I told him I wanted to try this thing where we have an extra pedal in the car, and we put the right-rear or left-rear brake on to balance the car.”

“All we had to do was put an extra master cylinder on the car, and a length of Aeroquip [brake hose] that went to the right rear calliper, so that when you pushed the normal pedal it would put both rear callipers on, and when you pressed the fiddle-brake it only activated the right rear.”

The modification was very basic, especially for Formula One, and Nichols said the innovation cost just “fifty quid’s worth of parts that we already had in the truck!”.

McLaren’s steer-brake / fiddle-brake explained

In the footwell of Hakkinen’s F1 car was three pedals; the ‘steer-brake’, the normal brake pedal and the throttle. The steer-brake pedal was quite stiff and the driver would have to press quite hard on it to use it. This way, Hakkinen and Coulthard wouldn’t have to worry about tapping it and spinning out.

The steer-brake pedal operated one rear brake on one side of the car. The side of the car that it operated changed depending on the race and was decided on a track basis. The main deciding factor was long high-speed corners in which drivers would normally experience a high amount of understeer. So if McLaren were set to race on a circuit with a few tricky righthand turns, the engineers would set up the cars to have the brake-steer pedal to operate the rear right brake.

“As you applied the brake mid-corner it would brake one of the rear wheels, and as you didn’t want to slow the car down, you’d open the throttle to compensate.”

“So it was a combination of pressing on two pedals at the same time. In doing that you’re putting more torque through the outside rear wheel and less through the inside, and that puts a yaw moment on the car to steer the car around the corner.”

Not only did the innovation help correct understeer, but it also improved cornering aerodynamics as the front wheels would be straighter and drivers didn’t have to carry as much front wing on corner entry, making the car more stable.

It didn’t take long for an eagle-eyed photographer to notice

McLaren began using their brake-steer trick in the second half of 1997 and were quickly found out in early 1998. During the Austrian GP of 1998, a photographer for F1 Racing magazine, Darren Heath, noticed that he could see both McLaren drivers’ rear brakes glowing mid-corner. This was very unusual to see, let alone on both cars of the same F1 team.

Thanks to some great instinct and intuition, Heath had a hunch that McLaren were using some sort of extra brake, a theory that eventually proved to be bang on the money. Heath was able to luckily, with just the right exposure settings, capture a shot of the footwell of Hakkinen’s car, revealing three foot pedals rather than two. 

As events progressed, the secret was revealed to the world, competitors tried to replicate and understand the technology and in the end, it was banned on the basis of four-wheel steering.

“obviously it was not realigning the wheels,” Tim Goss, chief test team engineer at the time, commented. “We called it brake-steer, which was unfortunate when we tried to argue that it wasn’t anything to do with steering! It was a bad choice of name from ourselves.”

By then, it was too late to change the name to ‘fiddle-brake’, a term invented by Ross Brawn, Ferraris technical director at the time. The ingenious, race-winning ‘fifty quid’ invention was already banned.

Although the infinitely clever steer-brake was banned in the end, it managed to serve a great purpose for a good few months and helped McLaren to win several grand prix.