At an altitude of 660 metres, the Red Bull Ring is high enough that there are some serious technical implications. Nothing cools as well, less downforce is produced, the effect on each type of engine varies. Combined with a grunt-rewarding layout – a significant uphill drag, lots of acceleration bursts from slow speed corners – this was all great news for Ferrari, bad for Mercedes.
The Mercedes is packaged so tightly at the rear that in this heatwave, at this altitude, its bodywork needed to be opened up significantly more than that of either Ferrari or Red Bull. The extra area of radiator outlet peeking above the suspension at the base of the engine cover was visibly greater on the Mercedes than its rivals. This not only interrupts an aerodynamically sensitive area around the diffuser, but that hotter air is less dense, thereby less effective in creating the pressure differentials that in turn create downforce.
Mercedes had to significantly open up bodywork to improve cooling in the Austrian heat
So the Mercedes’ usual downforce advantage was reduced, possibly even cancelled out. And even though the lap time cost of the car’s extra drag over the Ferrari was reduced by the high altitude, that altitude took more of Mercedes’ lap time (relative to Ferrari) than it gave.
The track was measured at 56C at 3pm, 10 minutes before the start. This was extreme – and very bad news — for the marginally-cooled Mercedes.
The two Mercedes were in no position to chase the Ferrari, regardless of tyre compounds. Their limitation was temperatures of engine, control electronics and tyres, but mainly engine. These conditions were beyond the design limits of the car – and they couldn’t even begin to contemplate running close behind other cars. So Bottas backed away from Leclerc and Hamilton did the same to Bottas.