SILVERSTONE -- Valtteri Bottas was the fastest driver in the opening practice session for the British Grand Prix after setting a new lap record at the Silverstone circuit on Friday morning.
Bottas held a 0.078s margin over Merceds teammate Lewis Hamilton, even though Hamilton set faster times in sectors one and two. The two Mercedes drivers opted not to use the super-soft tyre compound in the morning session, suggesting there is even more time to come from the world champions in the afternoon. Both cars also have new power units fitted this weekend -- their third of four for the season -- which should offer a performance boost this weekend.
Max Verstappen was 0.498s off Bottas in third after using the super-soft tyres on a five-lap run in his upgraded Red Bull. He was 0.338s ahead of teammate Daniel Ricciardo, who also used the super-soft tyres but over a longer run.
The Ferraris of Kimi Raikkonen and Sebastian Vettel were over a second off the pace after they both set times on the super-softs. Vettel completed one installation lap with the FIA's latest cockpit protection device -- the Shield - attached to his car. The Shield is a clear screen that wraps around the cockpit, leaving an opening above the driver to allow him to climb out in case of an accident. Vettel later spun at Becketts while on his super-soft tyre run, but managed to stop the car in the gravel and avoid a collision with the barrier.
Daniil Kvyat was seventh fastest in the Toro Rosso but encountered an issue at the end of the session that left him down on power. The Russian driver was 0.098 ahead of Fernando Alonso in eighth, who was running Honda's Spec Three power unit again after the team fitted a new Energy Store ahead of the session. The addition of the new component means Alonso will get a five-place grid penalty for Sunday, but that figure is expected to rise as the team makes further changes to his power unit after Friday practice.
Using the soft tyre, Felipe Massa was ninth fastest despite damaging the floor of his car on the exit of Copse. Both Williams suffered the same damage at the same corner during the session, forcing the team to change the floor on both cars during the session. Stoffel Vandoorne rounded out the top ten in the second McLaren, also running the Spec Three Honda power unit.
Carlos Sainz was 11th fastest for Toro Rosso ahead of the two Force Indias of Esteban Ocon and Sergio Perez that opted not to use the super-soft compound. Romain Grosjean was 14th for Haas ahead of Lance Stroll's Williams and Ferrari reserve driver Antonio Giovinazzi who was given an outing in Kevin Magnussen's Haas during the morning session.
Nico Hulkenberg and Jolyon Palmer were over three seconds off the pace in the Renaults and only faster than the two Saubers of Pascal Wehrlein and Marcus Ericsson.