Sebastian Vettel will use a different chassis for the remainder of the United States Grand Prix weekend, after a mysterious issue cost him significant running during Friday practice in Austin.
The German, who needs a top five finish to ensure the championship carries on for at least one more week to Mexico, was the third quickest man in Practice 2 at the Circuit of the Americas, but would not complete any significant long runs after returning to the pits with a strange feeling at the front of his Ferrari.
Though far from ideal as rain also caused some disruption in the morning, Vettel insists there is no immediate cause for concern going into the weekend based on the pace shown when out on track.
“It was a messy afternoon and not an easy session but the car is quick so we don’t need to worry,” he claimed.
“The main thing was that Kimi did some running so I think we got enough information but obviously I didn’t get too many laps so I need to find the rhythm tomorrow but as I said the car is quick so I am not too worried. We just need to make sure we get everything in order then it should be a good day.”
Just as frustrating, the issues meant Vettel and Ferrari couldn't complete a full assessment of the hefty upgrade package that has been brought for this weekend.
Explaining exactly what happened in the afternoon, which restricted the four-time world champion to just the qualifying simulation on the Ultrasoft tyre, he continued: “Before I probably took too much risk earlier in the session and lost the rear into Turn 19, it has been quite slippery there all day, it was my mistake.
“We lost a set of tyres but in the end I felt something was not right with the car so we came in a couple of times to check and then go out to double and triple check. We are looking into it to try to see something."
The introduction of a new chassis was later confirmed with no immediate cause found for the looseness that he reported over the radio, that car will have to be scrutineered before Vettel can head out on track for Practice 3 on Saturday.
