US GP: Sebastian Vettel takes new chassis after practice problems
Precautionary change on Friday night after troubled practice
Monday 30 October 2017 12:42, UK
Sebastian Vettel will use a new Ferrari chassis for the remainder of the US GP weekend after experiencing problems with his car in Friday practice.
Vettel, whose title challenge could be ended in Sunday's race, completed limited mileage in Practice Two after a spin into the gravel was followed by a suspected problem with his SF70-H's axle. As he returned the car to the pits, Vettel reported the front of the car felt like "jelly".
Ferrari have opted to change the chassis on precautionary grounds ahead of Saturday's running.
The car will be re-scrutineered ahead of Practice Three, with the change of monocoque approved by the FIA and not triggering any penalty.
Vettel finished third on the Practice Two timesheet but was half a second adrift of title rival Lewis Hamilton, who dominated the opening day's running at the Circuit of the Americas.
Hamilton can clinch his fourth world title on Sunday if he wins the race and Vettel finishes outside the top five.
Vettel described P2 as "complicated" but stressed that "the car is quick, so we don't need to worry too much about it".
"The only lap I had was the one with the ultrasofts. Before that, I made a mistake taking too much risk and pushing too early," he said after practice.
Hamilton fastest, Vettel falters
Why has Verstappen re-signed?
"The track was quite slippery and I lost the rear under braking. So, we lost a set of tires, and then again, towards the end of the session, I felt that something was not right with the car. So, we checked a couple of times and now we are looking at the car to see if we can find something. I need to find the rhythm tomorrow and make sure everything's in order.
"It's important to feel comfortable. Obviously we're missing some laps but I'm sure with a couple of successive laps tomorrow it should be better."
