Has the secret of McLaren tire cooling been revealed?

      McLaren's advantage in the past and this season is largely due to the more efficient performance of the tires on the track, with their rapid warming up and keeping the temperature in the operating range. The MCL39's ability to control tire temperature has attracted considerable interest from rivals. An attempt to explain how the team could achieve such an effect appeared on the channel of Martin Buchan, a former McLaren engineer.

      Buchan suggests that the MCL39 brake drum plays a major role in temperature control, which is confirmed by Red Bull's comments – the team admitted that it monitors the brake drums on rival cars using a thermal imager. They noticed that the brake drums of the MCL39 are cooler than those of competitors, which means less heat is transferred from the hub to the wheel and the tire itself.

      According to Buchan, the reason may be the combination of cooling air flows of the brakes and the brake drum under certain conditions. In a normal situation, the flows are separated, but as the tires heat up, the airflow changes direction due to the use of bimetallic plates that redirect the air. According to him, this is achieved through the use of materials with a changing phase state.

      Adding credibility is the fact that Buchan, while working at McLaren, defended his thesis on the use of phase–change materials in motorsport - it was about battery cooling, but a similar principle can be used in other areas.

      "The system is completely passive. It needs neither a mechanical nor an electric drive, and who looks inside the drum lid? Such a system is completely legal," says Buchan.