A FORMULA 1 RACER IS IN THE MIDDLE OF A RACE, dozens of laps to go. Everyone’s zooming over 300kph. But it’s time for repairs and tyre changes — time for a pit stop. The racer pulls in. Close to two dozen workers swarm on the vehicle. The car rises on jacks, all four tyres are changed, the driver's helmet visor is cleaned, the jacks drop and the car bolts away.
The most amazing part of all this — beyond the sheer precision and coordination required — is that the entire process is carried out in less time than it takes to read this sentence. In a pit stop, every millisecond counts, and even one extra could spell win or loss for the team.
The racing limelight may go to the stars in the cars, but despite appearances, they don’t top the podium all on their own. Pit stops are an integral element of racing, and the crews have it down to a fine art. In Nascar, a fast four-tyre pit stop typically takes between 11 to 13 seconds by a team of up to six people.
In endurance races like the Le Mans 24 Hours, meanwhile, pit stops tend to skew a little longer, though they still take less than a minute. It’s that kind of precision that broke records in June.
British F1 company Williams flew through a pit stop at a mind-blowing, blink-and-miss-it 1.89 seconds at the European Grand Prix in Baku, Azerbaijan last month. The first sub-two second pit stop record in F1 was set by the Red Bull team at the US Grand Prix in Texas in 2013 at 1.92 seconds. (The Williams run was originally clocked at 1.92, as well, but the team analysed data that suggests a slightly faster time.)
So, what actually happens in a pit stop? Too many things to list — but we’ll try anyway.
Precision is paramount.
First, in F1, the driver pulls into the tiny pit lane, right in front of the front jack operator at speeds approaching 60kph (37mph), and as many as 12 crew members change all four tyres. In endurance races, the driver may change, and the car may be filled with fuel, and with certain types of cars, crew dart in to clean headlamps and windscreens.
Whatever the race, precision is paramount. The driver’s stop must be perfectly timed to avoid hitting the waiting crew member, who then lifts the car hydraulically with the assistance of a rear jack operator, while another two crew members stabilise each side of the car.
Also crucial? Preparation. Three crew members are ready and waiting at each tyre. One uses a high-torque air wrench called a "wheel gun" to remove the singular lug nut from the car’s wheel. (In some cases, these crew are so practiced, they have fastened their wheel gun’s socket over the wheel nut before the car has even come to a complete stop.) The torque of these guns is so powerful, improper use can cause serious injury.
Next, the loose wheel is removed by another crew member. Yet another might attach the new wheel and the gun operator sets it in place. Once the operator removes the gun’s socket from the wheel’s axle, a watchful mechanic checks to make sure everything is properly secured. Finally, a signal to the crew: The driver is good to go.
The car hits the floor and the jack operators and stabilisers leap out of the way as the pit light indicates the driver can take off. And then it’s back to the races — ideally, only a few seconds later.
In the electric racing environment of the recently created Formula E, pit stops require the driver to swap between different cars, so only two pit team members are used to assist the driver with exit and entry. There’s little doubt, however: Formula 1 pit stop crews are the most extravagant.
“Pit stop speed is at its pinnacle right now”, says Pat Symonds, CTO of Williams F1. “I remember when a three-second stop was considered unbeatable. Now we’re constantly hovering around the two-second mark and occasionally breaking into the sub-two second times, as we saw in Baku.”
Crews have been able to achieve their record-breaking times due to a number of factors. For starters, they put in an incredible amount of practice. “Including any live (i.e. non-practice) stops during a race we will complete around 1,700 pit stops over the course of a season”, explains Symonds. “Practice is done at the track during a weekend and on a practice car we have at the factory.”
An F1 refuelling ban implemented by the FIA (Federation Internationale de l’Automobile) from the 2010 season — following on from a previous ban from 1984 to 1994 by the now-defunct body FISA (Fédération Internationale du Sport Automobile) — has notably decreased pit stop times over the last few years.
Pit-stop speed is at its pinnacle right now.
Why was refuelling banned in the first place? It's risky: There are a lot of health and safety concerns. Jos Verstappen’s car was engulfed in a fireball during the 1994 German GP (he escaped with minor burns to his face), while Kimi Räikkönen’s Ferrari caught fire in the 2009 Brazilian GP when Heikki Kovalainen, pulling out in front of his fellow Finn, sprayed fuel from a detached hose over his car. Due to such incidents, modern pit crews are made to sport fire-resistant Nomex suits similar to those used by the drivers themselves. It’s safer — and faster.
It will be interesting to see how pit stops evolve over the next few years, particularly if refuelling ever makes a return. It is a move that remains contentious, having the backing of many prominent racers due to the speed gains it brings, but the FIA remain divided on the issue. It’s hard to imagine how current pit times could possibly be improved further — 1.5-second stops, perhaps? However they evolve, F1 crews are the unsung heroes of professional race teams.
As Symonds says, “Other categories still have the same pit stop principle”, says Symonds, “But there’s just no category that can conduct a pit stop like Formula 1. It’s the pinnacle.”
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