Practice 3 Report - Damp

By Dan Knutson

Overnight rain left the track damp at the start of Free Practice 3 for the Mexican Grand Prix. Only in the last third of the session were the drivers able to get up to speed on slicks, and the fastest of all was Max Verstappen in the Red Bull.

The line-up for the weekend was: Mercedes – Lewis Hamilton and Valtteri Bottas; Ferrari – Sebastian Vettel and Kimi Raikkonen; Red Bull TAG Heuer – Daniel Ricciardo and Verstappen; Racing Point Force India Mercedes – Sergio Perez and Esteban Ocon; Williams Mercedes –Lance Stroll and Sergey Sirotkin; McLaren Renault – Fernando Alonso and Stoffel Vandoorne; Renault – Nico Hulkenberg and Carlos Sainz; Toro Rosso Honda – Brendon Hartley and Pierre Gasly; Haas Ferrari – Romain Grosjean and Kevin Magnussen; Sauber Ferrari – Marcus Ericsson and Charles Leclerc.

The Red Bulls had dominated Friday, posting times a full second faster than the opposition. Verstappen was the best of all with a time of 1:16.720 on Pirelli's hyper soft tire. The other two compounds available were the super soft and ultra soft.

Tires were the challenge on Friday.

"The difficulty is that you don't have any grip," Vettel said after posting the seventh quickest time Friday, "so we are sliding a lot, and the problem is if you don't have a lot of grip and downforce because the air is so thin, you don't get the tires to work. When the tires don't work then it is really tricky. So that is why you can see sometimes quite big jumps in lap times. If you don't get it right you are quite far off the pace. That will be the main job to get right for tomorrow because you have one lap in qually. With the hyper soft it should be a bit easier, but still it is tricky to keep a clean balance from the beginning to the end of the lap."

But the weather changed dramatically overnight with rain and cooler temperatures.

The ambient temperature at the start of the 60-minute session was 59 degrees Fahrenheit (15 degrees Centigrade) and the track temperature was 63 degrees Fahrenheit (17 degrees Centigrade).

Compare that to FP2 when the ambient temperature was 73 degrees Fahrenheit (23 degrees Centigrade) and the track temperature was 113 degrees Fahrenheit (45 degrees Centigrade).

Still, while the track had some damp patches, it was dry enough for some of the drivers to go out on slick tires in FP3. The rest were on Pirelli's intermediate rain tires.

"Some corners are still pretty wet, especially on the inside line on the exit of corners, but I think it should be dry pretty quickly," Gasly told the Toro Rosso team.

"Be careful in the pitlane, it is very slippery," McLaren told Alonso.

After the drivers had done their reconnaissance laps they headed back to the garages. Nobody was anxious to do any more running on the damp track, but a couple drivers tried another single lap.

"You are going to see teams just hanging out until the track gets drier," Red Bull boss Christian Horner told Sky TV.

At the midpoint of FP3 Alonso went out on hyper soft slicks and completed the first flying lap of the session with a time of 1:21.213. And soon several other drivers were on track.

"I know you don't hear this very often but we are P1," the team radioed to Alonso.

That P1 didn't last long as Raikkonen posted a 1:20.785 and then a 1:19.013.

The track was getting faster, and Leclerc got down to a 1:18.952. Vettel turned a 1:17.836.

Fifteen minutes remained in FP3 when Bottas parked his Mercedes in the stadium section. "Hydraulic failure," he radioed.

The Virtual Safety Car was deployed to that his car could be moved. Bottas was able to walk back to the paddock.

When things got going again, Leclerc set a lap time of 1:17.059.

Most of the drivers were on track in the final five minutes. Verstappen topped the times with a 1:16.284.

The session came to an end with Verstappen ahead of Hamilton, Vettel, Ricciardo, Raikkonen. Leclerc, Sainz, Gasly, Ericsson and Hulkenberg,