Nico Rosberg sets the pace in opening practice at Silverstone as Williams weekend gets off to the worst possible start.

Ahead of today's opening practice session the air temperature is 17 degrees C, while the track temperature is 27 degrees.

Tyre options this weekend are hard (prime) and medium (option). There are two DRS zone, the detection point of the first is before Turn 3, with the activation point after Turn 5, while the second detection point is at Turn 11 with the activation point after Turn 14.

A number of reserve drivers on duty this morning, most notably Susie Wolff who replaces Valtteri Bottas at Williams. Daniel Juncadella is in Adrian Sutil's Force India, Giedo Van der Garde is in for Nico Hulkenberg at Sauber and Robin Frijns replaces Kamui Kobayashi in the Caterham.

The lights go green and Magnussen gets the weekend underway, he is followed by Kvyat, Vergne, Gutierrez and Grosjean.

One by one the drivers take to the track, and within a couple of minutes all but Massa, Wolff and Hamilton have made an appearance. Indeed, the mechanics are working on the cars of the two Britons.

Raikkonen is told of strong head winds at Copse as Wolff finally leaves the pits.

Hamilton finally emerges from the pits his car sporting flo-vis in the sidepods. As he returns to the pits he complains that his steering wheel isn't straight. Massa also completes his first lap of the weekend.

The TV cameras pick up on Christijan Albers on the Caterham pit-wall.

Despite the extra set of tyres which usually mean more track action, there is a surprisingly long wait before any further action. Fourteen minutes into the session, Maldonado fires up the Renault power unit in his Lotus. He stops at the end of the pitlane to perform a practice start - a queue forms behind - but there is a problem and he has to be rescued and pushed back to his garage. Not a good start for the Enstone team.

Ericsson posts the first time of the weekend (50.811) but this is soon beaten by Button and then Wolff, who stops the clock at 44.212.

No sooner has Rosberg posted 40.100 than Button bangs in a 38.412.

Oh dear, Wolff has stopped on the run-off at Vale, she complains of a loss of oil pressure. As her car is pushed to safety the Scot shakes her head in obvious frustration.

As the times tumble - Vergne going quickest with a 38.020 - Caterham reveals a problem on Frijn's car which has meant having to remove the floor.

"It feels like we're overheating the fronts," claims Button.

Williams day gets a whole lot worse as Massa goers off into the barriers at Stowe. The front of the car is badly damaged but the Brazilian - celebrating (or rather not) his 200th Grand Prix - is OK. Replay shows that he ran wide and lost it on the Astroturf damaging the front and rear.

As Massa walks slowly back to the pits, the mood in the Williams garage is decidedly down, the team losing precious track time.

The resultant red flag means that at least the team can rescue Wolff's car. Indeed, both drivers and their cars eventually arrive back in the pitlane. However, the Scot is told that the issue on her car is not an easy fix and as a result she won't be going out again.

Officials announce that the session will re-start at 10:43.

The lights go green and Kvyat is first out of the box.

On-board lap with the Russian is quite disturbing, the car is on the very limit as nervous as hell.

At half-time, even with so little running, it's: Rosberg, Raikkonen, Alonso, Ricciardo, Magnussen, Kvyat, Vergne, Button, Hamilton and Gutierrez.