Ahead of today's second free practice session, the air temperature is 24 degrees, while the track temperature is 41 degrees. It remains bright, but with a bit more cloud.

World Championship leader Jenson Button could only manage eighth this morning, however, Brawn GP's honour was upheld by Barrichello who topped the timesheets.

There were problems aplenty for Red Bull with Vettel suffering an engine failure and Webb complaining of a vibration. Things didn't look too good for Toyota either, with Glock and Trulli rooted to the bottom of the timesheets.

Ferrari once again shows signs of improvement, as does McLaren, while BMW had a disappointing morning with Kubica describing his car as a "disaster".

When the lights go green, Buemi, Piquet and Rosberg lead the way. The German no doubt looking to do his 'usual' and top the Friday timesheets.

Buemi posts the first time of the afternoon (1:23.542), as Piquet goes second and Rosberg third. However, moments later Bourdais goes quickest with a 23.207. As in session one it is fast and furious.

As Red Bull attempt to find the root of Webber's vibration problem, the Australian reveals that he will miss the first half-hour of this afternoon's session. The Milton Keynes crew are working on Vettel's car also.

A 19.433 sees Rosberg go quickest as smoke and flames pour out of Kubica's BMW on the hill heading up to Casino. The Pole's 'disaster' of a day takes a turn for the worse.

"I can't push, I can't do anything," Bourdais tells his crew. Clearly another disgruntled driver.

Rosberg consolidates the top spot with a 18.486, as Kovalainen takes second, ahead of Massa and Buemi, only to be ousted by Button who crosses the line at 19.215.

An 18.361 sees Kovalainen go quickest, as Hamilton and Raikkonen take second and third.

Hamilton posts 18.124 to go quickest as Raikkonen improves to second with an 18.207. Kovalainen remains third ahead of Rosberg, Bourdais and Buemi.

Barrichello, currently eleventh, goes quickest in the middle sector finally crossing the line at 18.216 to go third.

From out of nowhere, Trulli produces an 18.190 to go second, however, he is quickly demoted by Alonso and Piquet who go first and second. Trulli subsequently splits the Renaults with a 17.801.

There's clearly little difference between the two tyre options - soft and super-soft - at this stage. Though it remains to be seen whether this will change as the weekend progresses.

Barrichello, Kovalainen, Alonso and Nakajima all take their turn at the top of the timesheets, the order constantly changing.

Hamilton goes quickest in the first sector, finally crossing the line at 175.294 to go fourth. The Englishman driving beautifully here this weekend and clearly enjoying himself… despite being disillusioned with the sport. Next time around he improves to second (16.881).

Hamilton goes quickest in the first two sectors but a poor final sector sees him fail to improve. Elsewhere, Trulli goes third as Glock goes quickest in the first sector.

A 16.637 sees Massa go quickest, the Brazilian having only been quickest in the middle sector. However, Hamilton continues his long and very fast run, posting a 16.523 to take the top spot.

Thirty-five minutes into the session, Vettel finally leaves the pits, however, the Red Bull crew continues to work on Webber's car.

Raikkonen posts 16.622 to go second, bringing back memories of the old days with McLarens and Ferraris filling four of the first five places.

"Try a little experiment," Massa is told by Rob Smedley, "adjust the front wing to minus-1 and hold it for the rest of the lap".

Vettel is up to eighth and pushing hard, but still no sign of his teammate. Barrichello improves to second as Buemi posts 16.983 to go ninth.

At half-time, it's: Hamilton, Barrichello, Raikkonen, Massa, Kovalainen, Alonso, Trulli, Vettel, Buemi and Bourdais.