Still slick track. Factory driver Mark Webber is in the midst of a thrilling race, clocking very good lap times in the 919 Hybrid. “Box, Mark, Box,” radios the racing engineer, requesting full service: refueling plus a new driver and tires. The pit team now takes over the race for around 50 seconds. Every movement is perfectly coordinated and has been practiced thousands of times. Just as on the track, every tenth of a second is crucial, and the crew wants to be faster than the competition. The pressure is enormous. Cars are refueled at every scheduled stop during endurance races. While the car is being fueled, it’s forbidden to change the wheels. That has to be done afterward. To minimize the downtime, tires and drivers are usually changed at the same stop. An extra break would take too much time. At the entrance to the pit, Mark slows down to 60 km/h. He unplugs the radio cable and pulls out the drinking tube. Then the action starts.
The pit lane is a dangerous place, and here it’s also slick from rain. It’s a real skill to bring the prototype to a perfect landing. The “lollipop man,” holding a large carbon-fiber sign to guide the car, is the only one allowed to be out in the pit lane. He is not permitted to touch the car and has to ensure that the lane is clear when the car leaves. The mechanics have to wait behind the line until the car has come to a complete stop.
The car has to stand on its wheels during the refueling process. A maximum of two mechanics may do it. At the same time, Mark pulls off the safety belt and opens the tiny car door. The switch is about to take place: Brendon Hartley runs up to him. One mechanic perches on the front hood, like a frog, to clean the windshield for good visibility. A maximum of two people are allowed to clean the windshield, headlights, rear lights, and camera. One person transfers data.
Mark and Brendon share the Porsche 919 Hybrid, sporting the number 17; the third member of their team is Timo Bernhard. Timo is ten centimeters shorter than the other two, which is why he drives in his own seat shell which he now has to remove when getting out. The car is permitted to carry a maximum of 68.3 liters of fuel. The full fueling procedure takes about 30 seconds, and will be performed around thirty times over the 24 hours.
As soon as the fueling mechanics have left the car, a crew member springs to the rear of the vehicle with a pneumatic line. The 870-kilo prototype rises up with a rumbling sound, and he dashes back behind the line. In the meantime, Brendon has closed the door but needs assistance buckling up. A mechanic lies on the side pod to help him.
In the WEC, only two mechanics are allowed to change the wheels at any time, and only one impact wrench may be active at a time. Sophisticated choreographies make this process run as rapidly as possible. One mechanic loosens the wheels on each side and takes them off. One man mounts the new wheels on the front axle and another on the rear.
Everything is finished after around 50 seconds. The crew practiced this procedure 1,053 times in Weissach during the year of preparation alone. The pit stops are extremely strenuous physically. A complete wheel with a tire weighs around 25 kilos. The pneumatic line is removed. The car hits the ground. Brendon steps on the gas. But no racing start, please – there’s a penalty if the wheels spin when starting up.
Text first published in the Porsche customer magazine Christophorus, No. 367.