Jules Bianchi emerged as the quickest driver on the second and final day of the Silverstone test on a gusty Wednesday in his Ferrari but was marginally slower than the top time from the preceding day.
The Frenchman, a member of the Ferrari driver academy, filled in for Kimi Raikkonen who was left bruised and is now recovering from his shunt at the British Grand Prix on Sunday.
Bianchi was only 0.020 seconds off the pace set on Tuesday by Williams' Felipe Massa and just 0.018 seconds slower than Fernando Alonso's fastest time over the British GP weekend.
"By the end of the day I got a really good feeling in the car, even if at the start, it was not so easy adapting to a car that's very different to the one I race," said Bianchi, who is racing for Marussia this season. "The parameters are completely different and I spent the first runs getting used to it.
"Putting on a Ferrari race suit is always a special feeling and I hope one day I can wear it as a race driver, even if I have a lot to learn," he added.
Danill Kvyat was second in the Toro Rosso ahead of McLaren driver Kevin Magussen, who clocked the most number of laps.
Sauber reserve Giedo van der Garde escaped injury after he lost the car and went off, crashing into the guardrail in the Copse Corner towards the end of the session. His time was enough for fourth.
Lewis Hamilton admittedly didn't have an easy day either as he caused an early red flag after he spun out at Stowe, following which an engine change limited his track time. The Briton featured fifth on the charts, nearly a second and a half adrift from the top time.
"At the end of the day, we were going to do more important runs but the red flag came out," Hamilton said. "It could have been a lot worse as it could have been raining or we could have even done no laps."
Valtteri Bottas was sixth but completed only 40 laps as Williams continued evaluating several new components on the car, which included bits for next year.
"The focus was mainly on testing aero parts with a few mechanical changes, so it was just out one lap and then back in to change a part and back out again," the Finn explained. "As a result we didn't do too many laps, but we have plenty of data."
Max Chilton was seventh in the Marussia followed by Daniel Juncadella in the Force India.
Red Bull and Lotus carried out development work for Pirelli with Sebastian Vettel ninth and Charles Pic in tenth. Power unit issues continued to dog the defending world champions, this time losing three hours of track time before it could be replaced.
"Even with that delay we were still able to complete Pirelli's plan for the day," said Red Bull race engineering co-ordinator Andy Damerum.
Julian Leal was last in the Caterham but the mileage accrued made the Colombian eligible for a Formula One superlicence. Due to a power unit issue in the morning Caterham was unable to run Rio Haryanto. The Indonesian had been due to drive in the afternoon session but with the time lost repairing the car he was unable to do so.
LARGER F1 TYRES TESTED
|© Andy Hone/ Pirelli
A set of new 18-inch concept tyres were introduced with Pic giving the new design its debut in the morning completing 14 laps on the rubber. The tyres were designed principally to showcase aesthetics rather than performance and lap times were not the focus.
"These are just a prototype concept, but if the teams decided that they wanted us to proceed in this direction, we have the capability to carry on development in this area and come up with a production-ready version in a comparatively short space of time," said Pirelli's motorsport director Paul Hembery.
The key technical advantage of an 18-inch tyre is a stiffer sidewall that helps maintain the structural rigidity of the tyre and also makes it easier for the tyre to maintain a constant pressure – as there is less actual air inside the tyre.
The new tyre is physically bigger, which makes it much more relevant to the tyres that are seen on the road, leading to greater technology transfer.
The new tyres tested have the same width as the current 13-inch tyres but a diameter that is bigger by 30mm. The weight is approximately the same as well, because although the diameter is bigger, there is a smaller sidewall. The total weight, including the rim, is around four kilograms heavier.
"It was a very early evaluation test and the different tyres and wheels affect the aerodynamics of the car quite a lot, but you could certainly feel that the tyres felt different to those we’re used to on an F1 car," Pic reported.
||Giedo van der Garde