Five Seconds Flat: The Anatomy Of A Pitstop

Five Seconds Flat: The Anatomy Of A Pitstop

Imagine, if you will, standing on the hard shoulder of motorway. Cars are whizzing by at 70mph without a care in the world, safely cocooned in their survival cells. Exposed to the elements though, you stand there, your hair being swept backwards by the rush of air flowing from the speeding motorists. You look up towards the traffic, eyeing the cars and accepting your fate. One driver makes eye contact, the stare piecing your mind as fear grips your motionless body. He kinks the car in your direction, aiming for you and seemingly not giving any thought to stopping. As your muscles tense you become aware of people around you, preparing for a surge of activity and rush of adrenaline. Your eyes close in blind panic. When you open them again, just a few moments later, the car is out of sight, hiding beneath you with only the intense heat giving away its position. You look down to where you hope your shins still are and see the front wing of a Formula One car, just inches away from a certain, painful catastrophe.

This is a Formula One pitstop, and you don’t have time to stand and stare.

Brief Introduction

Pitstops are an important part of any Formula One grand prix. In an era where strategy plays a huge role in the outcome of a race, a tenth gained while the car is stationary can win a driver or race. Conversely, loosing a tenth because of sticky wheel-nut can send a driver from the lead to midfield in next to no time. So how is this possible, how is this achieved? Let’s take a look at how a team pit a car, from hitting the limiter line at the start to hitting the delimiter line at the end, having changed the tyres and filled the tank, all in the time it took you to read the first paragraph.

Before I begin, I should quickly point out that some circuits have slightly different rules regarding the pitlane, but on the whole whenever I make blanket statements in this post I am excluding Monaco for the time being. The small Principality will be discussed later on.

On average a driver pits twice during a race. There are many factors to consider when figuring out a strategy, but during 2007 most drivers stopped by twice for new tyres. The reasons governing this partly come down to a new rule that came into force last season, whereby each driver had to run both sets of tyre during the grand prix. While it was possible to run a short stint on the soft compound and the remainder on the harder, it was judged that this would have placed too much pressure on the tyres and drivers and an extra stop would be beneficial.

The Call

As the driver starts the lap he will pit on he would usually get a radio message from his engineer. The language used varies and is likely to be the most easy to hear and understand phrase for the driver; remember, he is sitting only a few centimetres away from an engine that revs 19,000 times each minute. Listening doesn’t really play a big part in his job.

In this lap. In this lap.

Box. Box. Box.

Two of the most common phrases that pass into a drivers ear as they race towards the pitlane. Teams used to utter the word “Box” quite a lot in Formula One. When radios were in their infancy the quality of sound was terrible, and combined with the general noise the driver has to endure, the word to pit needs to be as clear and as concise as possible. The word “Pit” is actually quite soft. The “P” and “I” don’t come over very well on the radio and this can lead to confusion. Instead, the teams started to use the word “Box”. I cannot find the exact source of this word, but I do recall two possible resons for its use. The first possible explanation is that the teams are referring to the pit box, the part of the pitlane where the car stops. The second is that the word is the Italian for pit, but this doesn’t ring true with some searches online. Either way, the reason for its use is straight-forward; the “X” sound is much clearer and far less ambiguous. If a driver hears an “X” sound, it can only mean one thing.

The Approach

Kazuki Nakajima - 2007 Brazilian Grand PrixThe speed at which a Formula One car can travel down a pitlane is limited for safety. It never used to be this way but in the mid-nineties the governing body realised that pitting a car is actually quite dangerous. Limits were introduced at this time and currently they rest at 80kmh (~50mph) during the race. The limit starts at a designated point in the entry to the pitlane, well before any team personnel should be moving around, and the drivers can tell the point at which the limit begins by a white line painted across the pitlane.

Whenever a driver pits it is almost a given fact that his tyres will be changed, thus, the tyres currently on the car will be disgarded. Thus you will occasionally see a driver locking his front wheels just prior to the limit line, obviously not caring if they end up with a flat-spot. This is often called “attacking the line” and something Michael Schumacher became quite a master at. Of course, should a driver get this wrong and pass the line faster than the limit, a penalty will almost certainly be handed out.

At the limit line, the car must be travelling at less than the limit. The driver brakes and downshifts just prior to the line, and once there he activates the electronically controlled rev-limiter by pressing a button on his steering wheel. The driver would then release the brakes and floor the throttle. This causes the car to hit rev-limiter at just the right point to prevent the car from moving any faster than the limit. As the limiter is activated the fuel cover pops open in preparation for the pitstop, although much like your road car, the fuel is still kept safe from spillage.

Finding Your Garage

Lewis Hamilton - 2007 Malaysian Grand PrixAt this point the driver is able to relax a little. The car is travelling relatively slowly in a straight line. Often this is a good time to discuss anything with his engineer or take a sip of his drink. If the driver is sitting in the previous title winning car, his garage will be first in the pitlane. It is advantageous to have this spot because the angle needed to turn into the other spots is hindered by other teams; pitlanes tend to be quite cramped at the best of times. With the first spot though, the entry line is much smoother and the driver doesn’t have to worry about other team’s equipment or even cars getting in the way. For 2008, McLaren will be at the very far end of the pitlane as they were disqualified from the 2007 championship. With Ferrari at the beginning of the pitlane, the Scuderia will have an advantage over them, albeit very slight.

The pitlane is divided into two lanes. The fast lane is where the cars travel down at the speed limit, located nearest to the pitwall. The inner lane is where the cars are worked on by the mechanics while it is stationary. If a driver enters the pitlane with a problem and stops in the fast lane, the car may not be worked on by the mechanics. Should the mechanics touch the car (in an attempt to recover it), the car and driver are out of the race. If however a car stops in the inner lane part at or very close to the correct garage, the car can be pushed into place and worked on; this is considered a normal pitstop.

As the driver approaches his garage, often highlighted by the lollipop holder standing at the edge of the inner lane waving his instrument at the driver, the driver slows the car and turns into the slow lane. This is one of the most dangerous parts of a pitstop and where experience and practice really pays off. The garage isn’t an empty space. You can’t just pull in at any-old-angle and jump on the brakes. The garage is actually lined by 20 of your colleagues. Get it wrong and you face hitting a member of your team at 50mph. This is exactly what happened to Kazuki Nakajima during the 2007 Brazilian Grand Prix. As he pulled into his first F1 pitstop in anger, he got it wrong and clipped one mechanic, causing him to fall into another. Thankfully the mechanic wasn’t seriously injured, but it compromised Nakajima’s race and was generally unpleasant.

The Actual Stop

A pitstop in Formula One these days comprises of two essential parts; tyres and fuel. Fuelling wasn’t always a part of a pitstop as it is a very dangerous thing to be handling while under extreme pressure. However, systems have since been introduced to minimise and control the danger and since 1994 refuelling has played its part in a pitstop.

The Tyres

Giancarlo Fisichella - 2007 Turkish Grand PrixAs the car pulls into the garage, and assuming the driver hits his stopping mark exactly, to the centimetre, the wheel-gunners follow the wheel they are designated with. As the car stops the gunner leans forward, connects the gun to the nut and squeezes the trigger. By now the car will have been lifted by the jacks at the front and rear. Once the nut is off he leans back and his colleague, who already has a firm grip of the hot tyre slides it off while a third mechanic slides the new wheel on. As the new tyre is slid on the gunner leans forward again and replaces the nut. Once the gunner is happy the nut is firmly on he leans back, and ensuring no equipment is near the car raises a hand to indicate he is done.

Once all four tyres are changed, the car is lowered off its jacks and the lollipop man spins his lollipop around to tell the driver to pull in the clutch and select first gear. Some teams have introduced a light system on the lollipop, but as of 2007 most still still use the spinning technique.

Believe it or not, this is the easy part of a pitstop and only takes five seconds or so for the four tyres to be switched. Currently, McLaren hold the record for the fastest tyre change; it took them just 3.8 seconds.

The refuelling of the car almost always takes longer, so while the gunner sits on the tarmac with his hand in the air the other mechanics remove the old tyres to the garage along with any other bits and pieces that could interrupt their or someone else’s stop. It is also worth mentioning that a wheel gunner has a spare air-gun to hand in case the primary one fails as well as spare nuts. This forethought came in handy for BMW during the 2007 Spanish Grand Prix. As Nick Heidfeld registered his cue to leave the pitlane the front-right gunner was struggling with his nut. As the BMW pulled forwards the nut came flying off and rolled down the pitlane to the neighbouring garage. Heidfeld was forced to leave the pits and complete a slow lap before returning to get the wheel put on properly.

The Fuel

Giancarlo Fisichella - 2007 Turkish Grand PrixWhile the tyres are being changed, two large burly men lean forward over the engine cover just behind the drivers head and attach a heavy hose to the car. This is the refuelling rig, and when I say it requires two large burly men I’m not being sexist, I mean it really does take two large burly men. The rig is heavy even without fuel passing through it and the resulting dangers of getting it wrong can be catastrophic.

The fuel rig is prepped for each driver, pre-filled with the correct amount of juice for the next stint. Often there is a back-up rig as they can be notoriously unreliable, made so because of the stringent safety measures involved. Inside the lead-refuller’s helmet are two lights, red and green. As the hose is lowered down to the engine cover, the lead-refuller has to carefully align the hose with the cap and squarely insert one into the other. The action has to be precise as any awkwardness involved leads to the electronic device refusing to pass fuel. If done correctly, the hose pushes into the car and is locked into position by the refueller. The light inside the refuller’s helmet changes from red to green meaning fuel is now passing at no more than 12.1 litres per second.

The second refueller is important at this point because it is he who needs to take the weight of the heavy hose, allowing the lead refuller to concentrate on his job. Once the fuel is in the light inside the helmet changes back to red and the rig is pulled out exactly the same way as it went in. Again, not getting it square-on causes delays. Lifting the rig out is actually harder than getting it on as the refuller is now working against gravity. As soon as the hose is clear the refuellers step back, indicating to the lollipop man that they are done. Barring complications, this signals the end of a pitstop for the crew.

The Release

Jarno Trulli - 2007 Italian Grand PrixThe release of the car from the garage is another key area that has to be done correctly. Failing to get this right can lead to an accident or at minimum, a penalty from the stewards.

The refueller steps away and the lollipop man can see four hands in the air and all jacks are away from the car. A restarter is often placed at the rear, ready to restart the motor should the driver stall it. With the all-clear from the mechanics, the lollipop man looks back down the pitlane to see if there are any cars near to his driver. If a car is very close, or the driver in the previous garage has already been released, he must hold his driver by keeping the lollipop firmly down on the bridge of the car.

Once the pitlane is clear, the lollipop man lifts the lollipop cleanly into the air and steps to the side away from the car. The driver drops the clutch and pulls out into the fast lane, ensuring the rev-limiter is still activated. The driver may take this opportunity of not having much to do and take a tear-off strip from his visor, have another sip of drink or speak to his engineer via the radio. Once the car reaches the end of the pitlane a white line designates the end of the speed-restricted area, the rev-limiter is depressed and the car gets away, rejoining the race track at speed.

Why Monaco Is Different

The Monaco circuit is a little different when it comes to pitstops because of the restricted size of the area. Being held on normal every-day roads means that where some areas of other tracks are designed to be spacious, Monaco has to put up with what is already there. Thus, the pitlane at Monaco is narrow and relatively cramped in comparison. Due to the narrow lanes, the speed limit at Monaco is reduced to 60kph for the race, ensuring that the dangers are minimised and controlled better.

Anything Else?

Felipe Massa - 2007 Spanish Grand PrixThere are a few other regulations surrounding pitstops, mostly designed to control the dangers of 22 cars thundering down a pedestrianised area of the circuit. The teams are not allowed out of the actual garage until their car is approaching the pitlane. Personnel may cross the pitlane but they must do so with upmost care. It used to be quite common to see a manager or telemetrist wandering across the pitlane in the mid-nineties, but with advancements in radio technology there is less need for team members to be moving around during a race. For some reason I have a vivid memory of Patrick Head from Williams almost being run over by a pitting Formula One car as he crossed, but I can’t remember the race or the year.

Formula One also varies from most other racing series in that it only allows one pit crew per team. This means that during a race the pitstops of both cars have to be staggered sufficiently for the one crew to reconvene with all correct equipment. Occasionally, a team may queue its cars in the pitlane. This can be advantageous during a safety car period, but I can imagine the stress imposed on the pit crew during this kind of situation must be almost unbearable.

Along with the restarter, there is another member of the pit crew who is not usually called upon to work on the car; the fire extinguisher man. It is his (or her) job to standby with a handheld extinguisher just in case the worst happens. This extra job became mandatory after the horrific fire that was triggered on Jos Verstappen’s Benetton in 1994. The extinguisher must attempt to control a blaze long enough for the crew and driver to evacuate the area. Having said that, it is worth noting that the person holding the extinguisher is also employed by the team. When Felipe Massa had a minor fire on his engine cover at the Spanish Grand Prix, I don’t remember seeing any foam. Although the fire was very minimal and happened just as Massa was pulling away (it had extinguished itself by the time he got to the end of the pitlane), I still noted at the time that little or no attempt was made to put it out by the extinguisher.

5 comments

  • I remember reading an interview with Prost where he discussed the need for radio communication to be standardised within a team. Just before one of his early McLaren pit stops he radioed in to confirm everything was OK and the reply he got was ‘no problem’. Unfortunately all he heard was ‘problem’. Needless to say by the next race they had set phrases which could not be confused.

    I have been looking for any advantages in McLaren’s end of pit lane position. Reading this article I realised that the last pit has a straight exit as they don’t need to jink round the team in front.

    One thing you missed is that the wheels have a locking pin device which needs to be set after the nut is tightened.

  • ‘When Felipe Massa had a minor fire on his engine cover at the Spanish Grand Prix, I don’t remember seeing any foam’

    Bit of a coincidence, but I was watching the F1 07 Review on DVD last night and it showed this particular incident. As Massa pulls away one of the pit crew does attempt to put out the fire with an extinguisher but by then it’s too late.

  • I’m trying to find a video of Mike Gascoyne (or some other Spyker engineer) describing how the whole wheel nut locking system works. I remember seeing a short piece after the Hamilton incident at the Nurburgring last year, and it shows how complicated a simple nut can be. If I can find it I’ll update the post.

    Well spotted Dank.

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