07:59 Good morning from a dry and sunny Barcelona, where day two of the latest Formula 1 winter test is set to get underway.

08:00 The green came out slightly early here this morning, so the first few cars are already setting off on installation laps, led by Lotus.

08:01 Nick Heidfeld's Renault is the other car going for an immediate run, while Heikki Kovalainen takes the Lotus onto a second lap.

08:03 Correction, we think that's Vitaly Petrov in the Renault. The team has amended its plans after KERS software issues kept Petrov in the garage for much of Friday, so the Russian is driving this morning with Heidfeld taking over for the afternoon.

08:03 Jaime Alguersuari has taken the Toro Rosso out and back in following an installation run.

08:04 Installation laps happening thick and fast now, with Rubens Barrichello's Williams, Paul di Resta's Force India and Nico Rosberg's Mercedes making sure all is well.

08:05 Yesterday the track was damp at first and it was almost lunchtime before slicks could be used, but today is dry - albeit cold, with an air temperature of just 4.8 degrees and 10.6 on the track.

08:06 Fernando Alonso is giving the Ferrari a two-lap installation run this morning. Timo Glock is also heading out in the Virgin.

08:07 Next out is Jenson Button in the McLaren.

08:07 Alonso completes his run in the Ferrari.

08:08 Button is also doing two laps of checks on the McLaren.

08:09 The Red Bull is firing up ready to go out, and Sebastian Vettel emerges.

08:11 Everyone has now completed at least one installation lap, though no times have been set yet, as usual.

08:12 Novelty sight of the day is Tonio Liuzzi in the 2010 Hispania, with the Italian in the car today potentially as the precursor to a deal for the 2011 season.

Liuzzi: Hispania has good potential

08:13 There will also be a new sight at Lotus, where former Formula 2 driver Ricardo Teixeira will get 30 laps today. The Angolan is being considered for a test role, having also driven the car during a filming session at Valencia a fortnight ago. Story coming shortly.

08:15 Petrov sets off again for Renault - clearly eager to make up for the time lost yesterday when a KERS software issue kept the car in the garage for several hours.

08:16 Petrov told AUTOSPORT last night that he's getting frustrated with reliability at Renault: "We've still not found the limit or something close to it. We still need to work and understand how the tyres work and a lot of things." More on that later.

08:17 The Russian is going to set our first flying lap of the morning.

08:17 He starts off with a 1m38.223s.

08:18 Rosberg is coming out in the Mercedes too.

08:18 Petrov improves to 1m31.620s.

08:19 The track is totally dry this morning, Petrov is just working through Renault's planned test programme so may not be going for absolute flying laps at first.

08:19 Barrichello comes out too - Williams is another team that hasn't been able to notch up the sort of mileage it really wants yet.

08:20 As ever if you've got any questions for our testing team, you can email live@autosport.com. We've had a huge number over recent days so we can't answer everyone, but we'll get through as many as we can.

08:20 Petrov improves to a 1m29.124s as Rosberg does a 1m40.072s and Button sets off.

08:21 Less squinting and peering for AUTOSPORT Live today - we've got better seats in the commentary area so can see more of the pitlane.

08:21 Barrichello starts his day with a 1m32.168s.

08:22 Here's more on Teixeira's Lotus appearance today.

08:24 Barrichello goes fastest with a 1m28.363s, while Petrov improves to 1m28.922s and Rosberg does a 1m35.640s.

08:24 Kovalainen is onto a lap now as well.

08:24 Barrichello gets down to a 1m27.032s on his fifth lap of the day.

08:25 Button returned to the McLaren garage without setting a time. Toro Rosso and Red Bull are both going out.

08:25 Here's what Lotus is up to, via@MikeGascoyne: "Engine mapping runs at the moment for Heikki"

08:26 Sauber's plan for this morning is to concentrate on heavy fuel long runs to evaluate tyres.

08:27 Here's the full driver line-up for today: Vettel, Button, Alonso, Rosberg, Petrov/Heidfeld, Barrichello, di Resta, Kobayashi, Alguersuari, Kovalainen/Teixeira, Liuzzi, Glock

08:28 Red Bull is currently doing some pitstop practice. The team began this earlier by wheeling the car into the pitbox before the start of the session. Now Vettel is going round and coming at them at full speed.

08:28 Barrichello remains quickest, but Alguersuari is now up to second with a 1m27.372s.

08:29 After another practice pitstop from Red Bull, Vettel is brought back into the garage. He's yet to do a full flying lap.

08:29 Barrichello lowers the benchmark to 1m26.910s.

08:30 Red Bull is no longer covering up the rear of the RB7 as soon as it arrives in the pits, as it was yesterday. That could mean the car's not running whatever secretive part was on there on Friday.

08:30 Alguersuari improves to 1m27.101s, staying second.

08:31 Slightly quicker for Alguersuari with a 1m27.088s, while di Resta goes fourth with a 1m29.176s.

08:32 The session has been stopped.

08:32 The red flag is out, just looking to see who caused the problem.

08:33 Looks like it's either di Resta or Alonso, who had just gone out.

08:34 It's Alonso's Ferrari that has stopped on the track. It came to a halt at Turn 4.

08:34 Timing screen information says the track is clean, so nothing has been dropped by the car.

08:34 Recovery vehicles and a throng of marshals (who look excited) are around Alonso.

08:38 While the Ferrari is retrieved, you can catch up on yesterday's events in testing here, and PLUS subscribers can read Gary Anderson's analysis too.

08:39 Looks like Alonso just pulled to a halt and stopped on the edge of the circuit down at Turn 4.

08:39 Ferrari has been down and put a cover over the car as usual, and the marshals are about to lift the car onto the recovery truck.

08:39 In the meantime Alonso has returned to the pits in a SEAT people carrier - which raises a huge cheer from the stands.

08:40 The SEAT was red, so it did have something in common with a Ferrari.

08:41 As Alonso got out, the crowd watching from the roof of the pits rushed over to see if he appeared through the back of the garage.

08:41 Looking back at Turn 4, the Ferrari came to a halt on the inside of the track, before the turn-in point.

08:42 The crowd is still quite sparse at present, though fans have tended to flock in later in the day so far.

08:42 There's a constant, if not overwhelming, stream of people coming through the gates.

08:44 Before things got underway this morning, the Renault team got together to send a message to Robert Kubica.

Here's the latest news on the Pole's recovery: Kubica to leave intensive care

08:45 The Ferrari mechanics come out into the pitlane as the recovery truck arrives with Alonso's car, covered in a red sheet.

08:45 And as it returns, the session begins again.

08:45 They open the pits here while still unloading the car from the truck.

08:46 Kovalainen is first to get going in the Lotus.

08:46 Closely followed by di Resta, Rosberg, Kobayashi and Glock.

08:47 The Ferrari is wheeled back into the garage.

08:48 Glock and Vettel set off too.

08:49 Liuzzi is on track again for Hispania too.

08:50 Vettel is doing pitstop practice again.

08:50 The flatbed lorry that brought the Ferrari back to the pits was making its way back to its position by driving the wrong way up the pitlane. Fortunately it ducked through a gate before Vettel arrived.

08:51 Di Resta goes third with a 1m28.423s, as Rosberg follows him with a 1m28.545s and fourth place.

08:53 Liuzzi does a 1m35.824s in the Hispania.

08:53 Narain Karthikeyan said after his first try of the 2010 Hispania that it had been better than he expected. But he was coming from NASCAR Trucks, Liuzzi is coming from Force India...

08:54 The important thing for Liuzzi is the speed of the 2011 Hispania, and he's optimistic about that.

08:54 The Italian does a 1m33.467s next time around, while di Resta has improved his time slightly, remaining third with a 1m28.382s.

08:55 We have plans for some more guest appearances on Live over the next few days. We're hoping to line one up for today - though we won't say who until we know he can make it.

But we definitely have Toro Rosso reserve driver Daniel Ricciardo tomorrow afternoon and Pirelli boss Paul Hembery on Monday afternoon, so send in any questions you have for a fast Australian or the 2011 tyres, and we'll put as many as we can to them.

Our technical correspondent and veteran F1 designer Gary Anderson is here with us too, so send any questions you have for him to live@autosport.com and we'll get him on a few.

08:55 Liuzzi improves to 1m32.626s.

08:58 Vettel does another practice pitstop, overseen by Red Bull team manager Jonathan Wheatley.

08:58 Quite busy on the circuit now - Barrichello, di Resta, Robserg, Kobayashi, Liuzzi and Vettel all out.

08:59 Di Resta and Rosberg are doing high 1m28s, while Kobayashi is clearly doing the heavy fuel work Sauber promised as he laps in 1m31s and 1m32s.

08:59 An hour in, everyone has set a time except Alonso's broken Ferrari, Button and Vettel, though the latter's pitstop practice has included eight out/in-laps.

09:00 Rosberg has completed the most running so far with 17 laps, one ahead of current pacesetter Barrichello.

09:00 Kobayashi has pitted while Button comes out.

09:01 Di Resta has completed a six-lap run averaging 1m29.8s.

09:03 Vettel is finally pushed into the garage to end pitstop practice.

09:04 Alguersuari deposes Barrichello at the top of the times, a 1m26.885s makes the Toro Rosso fastest by 0.025s.

09:05 The situation in Bahrain is still at the forefront of everyone's thoughts. Here is the latest news:

Extra test planned if Bahrain cancelled

09:06 @InsideFerrari explains what went wrong for Alonso: "Not a good start of the second day of the session. Fernando stopped on track due to an electric problem. Anyway, the issue has been solved.

"Fernando will run again very soon. Tyres and set-up changes are the main objectives of today's programme."

09:06 Faster again for Alguersuari on his next lap, a 1m25.964s. He's now quickest by 0.9s.

09:06 Ferrari was right, Alonso's problem was fixed. He heads out again now.

09:08 Alguersuari trims another 0.017s off his best time to lower the benchmark to 1m25.947s.

09:08 Other than the Toro Rosso, it's currently just Rosberg and Alonso on the circuit.

09:11 Alguersuari pits at the end of the run that put him to the top of the times. He did four laps, averaging 1m26.277s.

09:12 As no one else has gone below 1m26.9s yet today, it seems a fair guess to say Alguersuari's tyres were near the softer end of the range and he wasn't over-loaded with fuel.

09:14 Kobayashi improves his time to a 1m30.849s, but remains seventh. Sauber is doing heavy-fuel work this morning.

09:16 After that earlier electrical glitch, Alonso proves the Ferrari is now in great health by banging in a 1m25.908s to go fastest of all.

09:17 The crowds are building up in the area of the grandstand opposite the Ferrari pits - and they're predictably happy to hear that Alonso is now on top.

09:18 Quicker again for Alonso with a 1m25.438s.

09:19 That puts him half a second ahead of Alguersuari. That's the second morning in a row that we've had a spell with a Spanish one-two on the timing screens.

09:20 Alonso follows that lap up with a 1m25.9s. Also on the circuit at present are Liuzzi, lapping in 1m33s, and Glock's Virgin.

09:22 Vettel comes out to commence what will be a six-lap run.

09:22 Di Resta is now out as well, while Glock has come in. Virgin still to do a proper lap time this morning.

09:23 AUTOSPORT.com's @gcreighton provides weather news: "Weather still bright and sunny here. Light clouds building from the direction of the city - expecting a bit more of that during the day "

09:24 He's now back in the pits.

09:24 Vettel sets his first flying lap of he day and goes third on a 1m26.558s.

09:24 Di Resta has improved his time to 1m27.826s.

09:26 Vettel improves to 1m26.158s, but stays third.

09:27 Barrichello comes back out for Williams, joining Vettel and di Resta.

09:29 Another slight improvement from di Resta, who laps in 1m27.708s, staying fifth.

09:30 Rosberg, Alguersuari and Glock start new runs.

09:31 Barrichello trims 0.4s off his time and does a 1m26.595s, which keeps him fourth.

09:33 Di Resta has pitted following a four-lap run, all in 1m27.7s and 1m27.8s bar a stray 1m32s in the middle.

09:34 Barrichello takes third from Vettel with a 1m26.093s.

09:34 That was a short run for Alonso - five laps averaging 1m25.849s.

09:35 Alguersuari caught Rosberg on his last lap, came past at the chicane, and then pulled away by about 5s.

09:36 Lotus has had a small problem to attend to, @MikeGascoyne: "Small water leak fixed, Heikki about to go fo a longer run"

09:36 Petrov improves his time by 0.9s to 1m28.027s, staying sixth.

09:38 Getting busy again: Alonso, Alguersuari, Barrichello, Petrov, Rosberg, Kovalainen and Glock all either on laps or just setting off.

09:39 Pitboard suggests another four-lap run for Alonso.

09:40 Alonso improves his fastest time by 0.2s, lapping in 1m25.299s to go 0.6s clear of second-placed Alguersuari.

09:41 Kovalainen has done his best time of the day too in the repaired Lotus, a 1m28.691s.

09:41 Vettel is out of the Red Bull, the car going up on stands for some work.

09:42 Di Resta jumps to second with a 1m25.859s, 0.5s behind Alonso. Kovalainen has improved his time by another half a second too.

09:44 Another small improvement from Kovalainen, the Lotus now on 1m28.028s.

09:45 A new best from Liuzzi as he gets to grips with the 2010 Hispania, he does a 1m31.058s.

09:45 Glock comes past the pits doing a constant-speed aero test in the Virgin.

09:47 Glock has yet to do a proper flying lap today, hence his best remains a 1m44.923s.

09:47 Liuzzi has improved again with a 1m30.627s.

09:48 Alonso's last run was five laps, all between 1m25.2s and 1m25.8s, except a mid-run 1m28.2s.

09:48 Di Resta's run to second place came on a stint of just two laps: a 25.8 and a 26.3.

09:48 Glock pits after another slow run down the straight.

09:49 Liuzzi finds another half-second in the Hispania and does a 1m30.192s. He's now ahead of Kobayashi, who has run with heavy fuel all morning.

09:50 Haven't seen much of Button this morning. He's only done seven laps, all of them installation runs, and there's little sign of activity down at McLaren at present.

09:50 Barrichello flies to the top of the standings with a 1m24.264s - that's 1.035s quicker than previous pacesetter Alonso.

09:52 Di Resta and Alguersuari are coming back out again.

09:54 Alguersuari jumps to second with a 1m25.259s, 0.04s ahead of Alonso and 0.9s behind Barrichello.

09:54 Barrichello is still out, his pace now up to mid-1m25s.

09:58 Alonso takes second back with a 1m25.247s, 0.983s behind Barrichello.

09:59 Rosberg goes from eighth to sixth, lapping in 1m28.001s.

10:02 Pictures are starting to flood in from the early action, so here's what Liuzzi driving a Hispania looks like.

10:03 Barrichello is onto his 10th lap of this run, which started with current top time 1m24.264s. He then did a 24.6 followed by a 25.3, and though he has dipped into the 1m26s region a little, he's now back into high-1m25s.

10:04 Alonso is onto lap five of this run. He did a 25.4, a 25.2, then backed off for a 1m34s, and is now back to 26.3.

10:04 Looks like Rosberg is beginning a long-ish run as his pace so far on this stint is all 1m28s and 1m29s. He's onto lap six.

10:05 Halfway through the morning session, it's still Barrichello on top by 0.9s over Alonso, with Alguersuari, di Resta and Vettel next up.

10:05 Barrichello is also top of the mileage list so far this morning with 44 laps in the bag already, three more than next-best man Rosberg.

10:06 The lowest tally belongs to McLaren. Button has only done seven laps, none of them timed runs, and has been in the garage for a long time, with no sign of activity or the car emerging soon.

10:06 The session has been stopped.

10:06 Red flags come out at Catalunya.

10:07 The session has been stopped due to debris on the track.

10:07 Reports of a piece of detached kerbing on the circuit at Turn 2.

10:09 It's warming up at the circuit, with the air temperature now 11.3 degrees and the track temperature 23.3.

10:10 There have been a lot of calls on live@autosport.com for some long-run analysis, so while we've got a break here is some from Friday afternoon's action by AUTOSPORT.com features editor @TeamAnglais:

Looking back over some of the longer runs from yesterday afternoon while the circuit was dry, I've picked out a few comparisons. Usual small print, we don't know the tyre compound or excess fuel for any of the runs so this is by no means conclusive. All we can do for now is look for trends in the laptimes.

Here are two 17-lap runs by Ferrari, with less than 10 minutes between them. On the first, Alonso starts out in the 1m27s and slips back through the 1m28s towards the end of the stint, ending with a solitary 1m29s lap before pitting. The steady drop-off of the tyre and the fact that he's lost just 1.7s in 16 laps suggest it wasn't either of the softer tyres.

One the second run, he takes it easier at the start - in the 1m30s - before getting down briefly to the 1m26s and then slipping back through the 1m28s. The sharp change in times between laps one and four suggests that fuel weight was not the determining factor, and the similarity of times throughout the stint indicate that both runs were probably on the same tyre compound - it could well be the hard, given that he did another 27 12 laps into each run. But by then, the two sets of tyres seem to be in the same condition regardless of what they did at the beginning.

Alonso
27.1, 27.3, 27.3, 27.7, 28.5, 27.4, 27.6, 28.0, 27.7, 28.3, 30.0, 27.9, 28.1, 28.7, 28.4, 28.8, 29.3

30.6, 30.4, 28.8, 26.8, 27.9, 27.0, 27.4, 27.4, 27.7, 27.4, 27.9, 27.7, 28.3, 28.4, 28.1, 28.8, 29.0

10:12 The session has restarted.

10:12 Kerbing problem solved, we're underway again.

10:13 No one immediately keen to rush back out on track.

10:14 Now Glock gets going in the Virgin.

10:16 Glock is doing another constant-speed aero test.

10:16 Di Resta comes out as well.

10:18 Renault update from @OfficialLRGP: "Vitaly is getting on with the programme he should have done yesterday. That means tyre work on scrubbed and new sets and set-up changes too."

10:19 Doesn't mean much at this stage of course as he's yet to do a 'real' lap time, but Glock's latest constant-speed aero test was his quickest yet, a 1m41.670s.

10:19 Alguersuari comes out again in the Toro Rosso.

10:24 While it's relatively quiet, @TeamAnglais provides some more long-run analysis:

Yesterday we also had a 13-lap run by Mercedes and an 11-lap run by McLaren, two teams that have question marks about their abilities over longer runs - Mercedes because its drop-off has been steeper than the other frontrunners in the previous tests, McLaren because it hasn't yet done enough long stints to show anything one way or the other.

Schumacher begins with a 27.5 but his time drops straight into the 28s and is nearly three seconds slower after just nine laps. Button meanwhile, starts in the 28s and is just two seconds slower than that after 10 laps - but by that time he would have been five seconds behind Schumacher if these times were set in a race.

Schumacher
27.5, 28.3, 28.6, 28.7, 28.4, 28.4, 29.4, 31.2, 30.2, 29.8, 29.8, 30.5, 30.2

Button
28.1, 28.9, 28.9, 29.1, 29.4, 30.2, 42.9, 30.1, 30.3, 30.2, 30.7

10:25 Liuzzi comes back out in the Hispania.

10:27 Toro Rosso has tended to do shorter runs so far in testing, but while Alguersuari is only three laps into his current stint, his 1m30s, 1m31s pace suggests heavy fuel this time.

10:27 Another man doing long runs this morning is Kobayashi, who is coming back out now.

10:28 Rosberg sets off as well.

10:31 Part three of @Team Anglais' long-run analysis:

Mercedes also did what looks like a race simulation run yesterday afternoon, with Schumacher out for 13, 16 and 16 laps with just quick tyre stops in between. The drop-off from the beginning to the end of the first stint was 3-4s, in the second stint it was 2.5-3s, and in the third 2-2.8s. We'll have to make our own guesses at tyre compounds - mine would be soft, medium or hard, medium or hard (the medium and hard tyres are the most difficult to distinguish between on laptimes alone).

The first tyre drops behind the second on the seventh lap. The next two stints are faster, which could be down to a reducing fuel load, with the fastest lap of the 'race' set at the beginning of the final stint. Here are the times to draw your own conclusions from:

Schumacher
30.4, 30.6, 31.3, 31.2, 31.5, 31.9, 32.5, 33.4, 33.5, 33.5, 33.6, 33.8, 34.8, P

30.3, 30.4, 31.2, 31.9, 32.4, 32.2, 31.3, 31.7, 31.7, 31.7, 31.7, 32.3, 32.5, 32.3, 32.8, 33.0, P

29.0, 29.8, 30.2, 30.2, 30.6, 30.2, 30.1, 31.0, 30.5, 31.0, 30.6, 30.4, 30.4, 30.9, 31.0, 31.8

The only other team to attempt something similar on Friday was Virgin, with Jerome D'Ambrosio doing a 53-lap run split into 13, 20 and 20. To begin with his times are four seconds slower than the Mercedes, but it evens out to around two seconds for most of the stints (bear in mind he's probably carrying more fuel) and he was just one second slower by the time Schumacher completed his run. The drop-off rate of D'Ambrosio's tyre stayed reasonably consistent with Schumacher's in each of the segments.

D'Ambrosio
34.9, 34.9, 34.7, 35.4, 34.9, 35.3, 35.4, 35.4, 35.5, 35.4, 35.8, 36.6, 36.6, P

33.6, 32.6, 32.9, 33.3, 33.2, 33.8, 33.4, 33.6, 33.7, 33.8, 34.3, 33.6, 34.1, 34.2, 35.5, 36.0, 35.0, 35.3, 36.5, 36.2, P

30.9, 31.1, 31.7, 31.3, 32.5, 31.8, 31.4, 31.5, 31.8, 32.1, 31.6, 31.9, 31.8, 32.5, 32.2, 32.9, 33.3, 33.7, 34.1, 36.3

10:36 Alguersuari's run continues onto a 10th lap. His times went right up to 1m35s, and are now into 1m33s. Pit board says five more laps to go.

10:38 Di Resta jumps to second with a 1m25.194s.

10:39 The Force India is one of the few cars running fairly light at the moment, and is closing on Alguersuari on the track.

10:39 Alguersuari is doing 1m34s, Robserg 1m29s and Kobayashi 1m31s on longer runs.

10:40 Latest weather news via @gcreighton: "As forecast by @radarguruf1, it is getting a little hazy here - nothing like the cloudless skies we had yesterday. Air temp now 12, track 25"

10:41 Di Resta caught up with Alguersuari and had a look at getting past, but comes into the pits instead. He's been sticking to two-lap sprint runs in recent hours.

10:43 Rosberg's pace suggested a longer run was likely, but he pits after three laps in 1m29.8s and 1m29.9s.

10:44 Current pacesetter Barrichello comes back out.

10:46 Alguersuari's times are now right up to 1m37s.

10:46 A new fastest time straightaway from Barrichello, who improves by a tenth over his previous best with a 1m24.126s.

10:47 Red Bull is just reinstalling the seat in Vettel's RB7.

10:47 Petrov does his best time of the day, a 1m27.697s, putting him sixth.

10:50 Barrichello's times are dropping off slightly, he followed his 24.1 with a 24.8 and a 25.2.

10:53 Liuzzi comes out for another run in the Hispania, while Barrichello's pace reaches 1m26s. Petrov is lapping in 1m27s and 1m28s as his run continues.

10:54 Still no signs of movement at the McLaren garage.

10:56 Glock is coming back out, will we see Virgin go for a time on this run? Despite being 17s off the pace and having only done installation laps and aero tests, Glock has actually managed 20 laps today.

10:58 Petrov completes an eight-lap run, averaging 1m28.7s. He's now done 34 laps this morning, which should please him given his worries about Renault's reliability yesterday:

Petrov: Reliability needed to judge R31

10:59 The crowd is now building up in the double-deck grandstand opposite the pits, particularly across from Ferrari.

11:01 This morning the Spanish fans were concerned to see Alonso stop on-track with an electrical problem before he could do a flying lap, but the repair was carried out extremely swiftly and Alonso shot to the top of the times when he rejoined half an hour later.

He's now third, having done 25 laps in total.

11:03 Barrichello has completed a 10-lap run. He averaged 1m26.4s, having started off with 1m24.1s and ended up in 1m27s and 1m28s.

11:04 Someone in the grandstand crowd has brought an airhorn today, and they decided it was worth a blast as Alguersuari pulled out of the Toro Rosso pit.

11:05 Fortunately we seem to have been spared the loud music from the circuit PA so far today.

11:05 Vettel's Red Bull comes down from the jack stands, and the world champion climbs in.

11:05 On track at present: Alguersuari, Petrov and Rosberg.

11:06 Barrichello still fastest by a second over di Resta, Alonso, Alguersuari and Vettel, and Barrichello is still the busiest driver of the morning too, with 56 laps logged already.

11:06 The Red Bull has been in the garage for 90 minutes receiving attention from the team.

11:07 Lotus has had a couple of small glitches today, after the earlier water leak, here's the latest from @MikeGascoyne: "Just fixing a fuel pressure problem on Heikki's car, back out again before lunch"

11:07 The screens part outside the Red Bull garage and Vettel is away.

11:08 A big improvement by Rosberg, who goes up to sixth on 1m26.605s.

11:09 He goes slightly quicker again next time past with a 1m25.745s to take fifth from Vettel.

11:09 Alguersuari's latest run will last for 13 more laps. Vettel is only due to do two.

11:10 A rapid improvement from Vettel, who jumps to second with a 1m25.025s.

11:12 Vettel improves his time to 1m24.854s.

11:13 @OfficialLRGP shows how the crowds are gathering today.

11:14 We're in the glass bit at the top, on the far end.

11:14 We've got AUTOSPORT technical correspondent Gary Anderson on hand this weekend, so feel free to send your complicated technical questions to live@autosport.com while he's here to have his brains picked.

11:15 As the Red Bull pitboard promised, Vettel's run was only two laps - the 25.0 and 24.8.

11:16 Vettel now comes back out again.

11:16 Liuzzi has done his fastest time of the day on his re-emergence from the pits, lapping in 1m28.580s.

11:17 Red Bull pitboard suggests this will be another quick two-lap burst from Vettel.

11:18 For comparison when looking at Liuzzi, Karthikeyan's best yesterday was a 1m28.3s.

11:18 Vettel goes quicker again with a 1m24.649s, now within half a second of pacesetter Barrichello.

11:19 Back to Hispania for a moment, when judging Karthikeyan/Liuzzi, bear in mind the Indian is readjusting to F1 after several years spent driving pretty much every type of racing cars (NASCAR Trucks, LMP1 Audis, Superleague singles-seaters), whereas Liuzzi is coming off a full F1 season with Force India.

11:19 Consistent pace from Liuzzi, whose 28.5 is followed by a 28.6.

11:20 Vettel's second lap was a 25.1. We expect him to pit now.

11:21 Sure enough, Vettel heads for the pits.

11:22 Lotus' @MikeGascoyne explains recent gremlins and a slight change of plan for test driver candidate Teixeira: "Heikki out again, collector filter was blocked so problem fixed now. Ricardo will get his run after lunch now"

11:25 Possibly a longer run beginning from Alonso as he starts off this stint with two consecutive 1m28.1s.

11:26 Barrichello goes a little quicker than earlier, improving the day's top time to 1m24.042s.

11:26 Kovalainen improves to a 1m26.421s in seventh place, after a bit of confusion on the timing system when it initially thought Teixeira was now getting his test run.

11:27 Ex-F2 driver Teixeira will now get his 30-lap try-out after lunch. The Angolan is hoping to land a Lotus test drive.

11:29 Alonso's Ferrari comes down the pits straight right behind Alguersuari's Toro Rosso.

11:29 As the Toro Rosso is Ferrari-powered, perhaps they've agreed to try the adjustable rear wing system together?

11:29 Rosberg does a new best time of the day for Mercedes in sixth place, a 1m25.745s.

11:30 A quick drop-off for Barrichello on this run. His 24.0 was followed by a 25.6 and a 26.0.

11:32 Speaking of Williams pace, and following the analysis of some of yesterday's longer stints, Theodoros Dragonas asks: "How are Williams's long-run stints compared with Ferrari's and Red Bull's? Is the FW33 as consistent in long runs as these two cars?"

AUTOSPORT.com features editor @TeamAnglais says:

Williams has done a few longer stints this morning, but still nothing approaching the length of the comparisons I did earlier. The most recent outings were back-to-back 11 and 10-lap runs.

Both began in the 1m24s and slipped pretty quickly to the 1m26s, suggesting Barrichello was using the soft tyre. On the first run, after the initial slide on lap four, his times remained constant for the rest of the stint, whereas on the second the times kept on dropping.

With shorter stints like these it's a lot harder to read into what the team might be doing because the number of variables increases the shorter the run, with both fuel load and what the team might be trying to achieve.

Barrichello
24.2, 24.6, 25.3, 26.0, 26.2, 26.0, 25.7, 25.6, 25.8, 26.0, 25.6

24.1, 24.8, 25.2, 25.6, 26.2, 26.9, 27.0, 27.8, 27.9, 28.9

11:32 Vettel goes quickest with a 1m23.410s.

11:32 That puts him 0.6s ahead of Barrichello, as the Red Bull does what looks like another short run.

11:33 Vettel's second lap of that run was a 1m24.1s.

11:33 That was another two-lap stint for Vettel, he returns to the pits.

11:35 Looks like Red Bull is getting ready for another practice pitstop now.

11:36 Petrov improves his time very slightly, going a tenth quicker with a 1m27.410s.

11:37 But he will be encouraged to have achieved 48 laps so far today.

11:38 Virgin hasn't done a fully-fledged flying lap yet, but the team is sticking with systems checks this morning, as new parts are arriving - probably in hand luggage - for this afternoon, when it intends to do a lot of running.

11:38 Lots of people are emailing live@autosport.com to ask what's wrong with McLaren, where Button has only done seven installation laps. We're not sure yet, but are working on getting information from the team.

11:38 Vettel raises the bar with a 1m23.315s, a tenth quicker than his last benchmark.

11:39 This will be his fourth straight two-lap run, looks like Red Bull is finally showing its hand in qualifying mode. He pits again.

11:41 We're not far from the lunchbreak at Catalunya - the track will fall quiet between 1pm and 2pm local time.

11:44 Alonso recently rejoined the track after some repairs, @InsideFerrari: "Another small issue cost us a bit more time so today's programme has to be rearranged."

11:44 Vettel sets out for another run - will we see the fastest time beaten again?

11:45 Kobayashi goes a little quicker with a 1m29.498s. Sauber is doing heavy fuel work this morning.

11:46 Vettel didn't go for a flying lap that time, he's back in.

11:47 @gcreighton is out trackside for us at present: "Big lock-up under braking by di Resta at Turn 10, he's forced to take the old part of the circuit as an escape"

11:47 Testing might get a bit quiet either side of the lunch break as teams wind down their morning programmes and prepare for the afternoon. So get in touch and let us know what you're up to.

At Jerez we had the Franchittis following Live from their Citroen hire car in the paddock, DTM racers Susie Stoddart and Maro Engel reading from the top of an Alp and a Brazilian beach respectively, and one chap in Chester watching us on a boat. Can anyone beat that? live@autosport.com if you can.

11:49 Here's Lotus's plan of action via @MikeGascoyne: "Finished for lunch, Ricardo will be in for an hour after lunch and then hopefully a race distance for Heikki"

11:54 Pacesetter Vettel is now working on pitstop practice again.

11:54 After a very long wait in the McLaren garage, Button is back out and going onto a second lap.

11:54 He's yet to set a time today.

11:55 Some more trackside observations from AUTOSPORT.com's @gcreighton:

"The Red Bull has a very aggressive off-throttle exhaust note. It's a bit like the pit limiter is on as Vettel rounds the apex.

"Fascinating to see the lateral flexing of the Williams rear wing pillar. Mark Hughes has a great column on it in AUTOSPORT's current issue"

11:55 Button logs a 1m27.435s, going ninth.

11:55 Now he improves to 1m27.027s.

11:56 AUTOSPORT F1 editor @eddstrawF1 has learned that it was a hydraulic issue that kept the McLaren in the garage.

11:56 A surge in pace from Rosberg, who leaps to third with a 1m24.730s.

11:57 Petrov goes ahead of Button into eighth with a 1m26.884s.

11:58 Button does a 27.5 on his next lap.

11:59 Followed by a 27.8.

12:00 Chequered flag comes out.

12:01 It's the lunchbreak at the Barcelona circuit, so we're off for an hour's break as well while there's no track activity.

12:01 Vettel leads by 0.7s over Barrichello at this point, with Rosberg, di Resta and Alonso completing the top five.

12:02 Barrichello's 66 laps is the top tally of the morning, followed by 61 each for Kobayashi and Rosberg, and 60 for Petrov.

But Button has only managed 14 laps after hydraulic issues in the McLaren.

12:02 We'll be back when testing resumes at 2pm local time.

12:06 Just before we go... no sign of any viewers on boats yet this week, but we do have another Alpine resident among us. Yannick Daxelhoffer even took a pic of his Swiss Alps for us.

Following AUTOSPORT Live from somewhere unusual? Email live@autosport.com and let us know.

13:00 Welcome back to Barcelona's Catalunya circuit, where testing is about to resume after the scheduled lunchbreak.

13:03 AUTOSPORT.com features editor @TeamAnglais makes it back to the commentary position in time: "hells bells. If @MBrundleF1 thinks he has it bad trying to get from his grid walk to the commentary box in 5mins, he should try it from the other side of the paddock"

13:03 Glock is first out this afternoon in the Virgin.

13:04 We're also set to see Ricardo Teixeira having his first public run in the Lotus imminently. @MikeGascoyne: "Ricardo out for his first run, big moment for him. Longish run just to build up speed slowly"

13:04 And sure enough, it's the Lotus out next.

13:04 Former F2 and GP2 driver Teixeira is angling for a testing role with Lotus. He has already driven the car in a filming session at Valencia and is set to get an hour of running now too.

13:06 Teixeira starts off with a 1m39s then a 1m35s.

13:07 Meanwhile after a morning of system checks, Glock gets Virgin up to speed with a 1m29.963s.

13:07 Button brings the McLaren out again too. Hydraulic problems cost him most of the morning.

13:08 There's a driver change at Renault for the next session. Heidfeld was supposed to get the whole day, but Petrov was put in for the morning because a KERS issue denied him a lot of running on Friday, @OfficialLRGP: "Nick takes over the R31 this afternoon. The guys are just working on the car now so he should be out soon."

13:08 Teixeira improves to a 1m35.121s.

13:09 Button improves to seventh place with a 1m26.036s, as Vettel comes out again. The Red Bull was fastest this morning after a string of qualifying-style two-lap runs.

13:10 On the subject of following Live from unique locations, James Hamett said: "Can't quite beat the up-the-mountain live tracking, but for something a bit different, I'm sat on a 1920s electric tram from Exeter, eating my lunch alongside the River Axe in East Devon.

"Just checking out the morning's commentary before getting back to work. Great feed, shame I can't keep it live whilst at work, but will check it out later. Keep up the good work."

Shame he's probably back at work now and won't see his shout out.

13:10 Glock improves to 1m29.488s in the Virgin.

13:10 Teixeira has settled into lapping in 1m35s.

13:11 Glock pits to wrap up that outing in his Virgin.

13:12 Mercedes has been switching between the slotted and not-slotted front wing this morning. We hear its new front wing won't be ready until the next test at the earliest.

Perhaps one of the regular live@autosport.com emailers from the Mercedes GP factory can fill us in, if they've finished today's serving of much-improved lasagne.

13:15 Vettel is back in the Red Bull garage after a quick installation lap.

13:16 The word from the paddock over lunch is that Red Bull is planning a full race distance this afternoon.

13:16 Which also means Vettel's session-topping short runs before lunch were a qualifying simulation.

13:17 We'll be keeping a close eye on the Red Bull's times once Vettel heads out to begin his series of long runs.

13:19 Paul di Resta is the only man on track at the moment in his Force India.

13:22 Glock and Kobayashi join in for some post-lunch running. The latter was looking very relaxed as he headed back to the Sauber garage after the break.

13:24 The screens are pulled away from the Red Bull garage and Vettel pulls forwards, but stops with the engine running.

13:24 After a brief cooling test, perhaps simulating the grid procedure, Vettel is off out of the pits.

13:26 Vettel is through the pits after a single tour, and he's doing burn outs to warm the tyres as they do when heading to the grid.

13:28 It's a long pause at the end of the pitlane and Vettel's away after completing the start procedure.

13:29 66 laps on Vettel's pitboard so he's underway on Red Bull's race simulation.

13:30 Elsewhere, Button is out in the McLaren while Kobayashi and Teixeira also circulate.

13:32 The first lap of Vettel's race is a 1m29.759s - we also know for sure that the Red Bull is fully fuelled for another 65 tours.

13:33 Button clocks a 1m24.923s and the McLaren is now fourth fastest in the headline times. He heads to the garage.

13:34 We can now confirm that this is the second consecutive test to have AUTOSPORT Live followed from a boat.

Jeff & Lelia Robinson say: "We're on our boat in the anchorage off Cartagena de Indies in Colombia - its 0730 here, so we have checked in just in time for your lunch!"

13:34 Vettel clocks a 1m30.361 for his third lap on full tanks.

13:35 Schumacher's race simulation yesterday was a three-stopper, so it will be interesting to see what strategy Red Bull has planned.

13:40 It's a 1m30.878s on Vettel's sixth lap as the heavy car begins to sap the life from his tyres.

13:41 The only other man on track at the moment is Glock.

13:45 That's 10 laps now for Vettel at the beginning of his race distance. His Pirellis continue to fade with the latest lap a 1m32.564s.

13:46 And the Red Bull crew is out for Vettel's first stop of the race - a pretty short first stint!

13:46 There's a bit of dithering at the rear of the Red Bull and he's being held in the pitbox for the moment.

13:47 The RB7 fires up again and Vettel is away on a fresh set of tyres.

13:49 Teixeira clocks his best at a 1m32.720s. @MikeGascoyne has just revealed that the Lotus is on a new set of hard tyres.

13:49 Button is off out again in the McLaren.

13:50 Heidfeld has also taken over the Renault, a little later than originally planned. He clocks his first time at a 1m31.738s.

13:53 Vettel's first flyer of his second stint is a 1m29.846s, followed up with a 1m29.248s

13:54 Heidfeld is building up to speed on his first run of the day and is now 11th fastest overall with a lap of 1m29.414s.

13:55 L50 is shown to world champion Vettel as he flashes past his team on the pitwall.

13:55 Button is also looking to do a longer run, with his pitboard suggesting another 17 laps are planned.

13:56 Vettel is still in the 1m29s on this set of tyres after four laps, suggesting the slightly lighter car is now being more gentle on the rubber.

13:57 Of course there is no change to the rule requiring each driver to run both tyre compounds during the race, so it is also possible the Red Bull has switched to a harder tyre.

13:59 Last season's strategy almost always ended up with soft tyres used in Q3 and therefore the first stint of the race. That's possibly what we've just seen from Red Bull - and some pretty significant data on how that was handled by the tyres.

14:00 Button is now five laps into his run and lapping on a similar pace to Vettel in the late 1m29s bracket.

14:01 Rosberg has also kicked off a run in his Mercedes, lapping in the mid 1m32s.

14:03 Vettel now nine laps in to his second stint and only just edging into the 1m30s, with this set of tyres looking a lot more durable as the fuel burns off.

14:04 To answer a lot of questions we're getting in the live@autosport.com mailbox about Williams's KERS, we can confirm that the team is running the energy recovery device on the FW33.

14:06 Glock sets his fastest time of the day so far with a 1m28.972s lap in his Virgin. The German is now 12th quickest.

14:07 Button's pitboard suggests another 10 laps to on the McLaren's run. His times have been in the mid 1m30s bracket for the last few laps.

14:08 Carlos Caicedo has emailed us with a correction to the location of today's boat audience. The name is in fact Cartagena de Indias, which apparently used to be the main commercial port for the Spanish until they were kicked out of the region. In 1984 it was designated a world heritage site by UNESCO, and Carlos reckons it's a lovely tourist destination.

I wasn't expecting I would learn about that today, as I drove through the circuit gates this morning.

14:10 Vettel has 40 laps left in his race and is now 14 laps into the second stint. His times are now slowly fading into the 1m31s.

14:11 Red Bull are out in the pitlane and here comes Vettel.

14:11 It's a slick stop this time and the world champion is away again on fresh rubber.

14:13 14 flying laps on that second stint for Vettel - the last a 1m32.146s, having started with a 1m29.846 on fresh tyres.

14:13 Button is also 14 laps into his run and in the 1m32s as well.

14:15 Button slows into Turn 10 to let Barrichello through in his Williams. He pits the McLaren.

14:16 There's no pit crew out at McLaren, so this isn't a race simulation just yet. The MP4-26 is wheeled back into the garage.

14:17 No sign of Alonso's Ferrari at the moment. The Spaniard hasn't been on track since before lunch.

14:18 Thanks to the screens across the doors, we can't see a lot of what is going on in the Ferrari garage from our vantage point high atop the main grandstand.

14:19 Vettel has kicked off his third stint with a couple of laps in the mid 1m28s bracket.

14:21 After a frustrating day one, the Renault is proving reliable so far today with Heidfeld now in the pits after 16 laps this afternoon.

14:22 Looks like Rosberg could be trying a race simulation in the Mercedes as well - he recently pitted and is straight back out on a long run.

14:23 If that was a first stint for Rosberg, it lasted 11 laps and featured a lot of running in the 1m32s and slower.

14:24 The red flag is out.

14:25 Red Bull respond immediately with a pitstop for Vettel, but this is an unwelcome interruption to his race simulation.

14:26 It looks like Paul di Resta in the Force India has caused the stoppage.

14:27 The timing screen tells us the Force India is in the gravel at Turn 1.

14:29 The recovery crew are out in force to collect di Resta and his car.

14:30 We can't see it properly from up here, but @EddstrawF1 is down there and tells us di Resta locked up and went off, but it's not clear why.

14:31 While things are quiet, let's have a look at the questions to live@autosport.com ...

14:33 Kamil in Galway asks: In all the tests this year, Ferrari has been the only team consistently doing over 100 laps each day. Others are doing most of the time 50-60. I know that problems occur, but shouldn't they use track more and make the most of it?

AUTOSPORT F1 editor @eddstrawF1 says:

"We saw this pattern last year – Ferrari has generally been able to put a car on the track straight out of the box that is pretty reliable (Felipe Massa's fire in Valencia, which I'm told was caused by a badly-clamped oil line, excepted). Ferrari has done the most mileage in the eight-and-a-half test days we've had so far, which you'd expect for a team that has produced a very reliable car.

"Ranged against that, the absurdly re-named Ferrari F 150th Italia appears more conservative than many teams, so perhaps inevitably that conservatism engineers in reliability. Both this and last year, Ferrari has got down to long runs very quickly and that pattern seems to be holding."

14:34 The Force India is back in the pits and the session resumes.

14:36 Kobayashi is the first man out, followed by Kovalainen - who is now back in the Lotus after that brief outing for Teixeira.

14:37 Red Bull has taken the opportunity to check over Vettel's RB7 and he's now off out to resume his race simulation.

14:38 Vettel was seven laps into his third stint when the red came out. The team is picking up where he left off, with 29 laps of the race to go.

14:39 Alonso is now out in his Ferrari for the first time this afternoon.

14:40 Alguersuari has improved his best time of the day in the Toro Rosso, clocking a 1m24.432s. He's third fastest.

14:41 Alonso also kicks off a run with his best time of the day so far. A 1m24.449s for the Spaniard, who is fourth fastest overall.

14:42 Vettel has unexpectedly turned up at the Red Bull garage.

14:43 The world champion's pitboard was showing 28 laps to go in his race simulation but the RB7 is now back in the garage.

14:46 Button heads out in the McLaren, joining Alonso, Rosberg, Kovalainen and Heidfeld on track.

14:47 Down at Red Bull, Vettel has stepped out of the RB7 and the mechanics are working on the car. It does look like a problem has cropped up.

14:50 Rosberg looks to be pressing on with his race simulation, but is again lapping in the 1m32s.

14:51 Gert Vermersch in Belgium asks about the constant speed aero tests we've seen many teams trying on the main straights: Greetings and keep up the good work! Could you explain to me what the use of these slow speed aero tests is? Why aren't they going full throttle?

AUTOSPORT F1 editor @eddstrawF1 says:

"As you say, the aero tests are conducted on the main straight by a driver holding a constant speed (often with the assistance of the pit-lane speed limiter set to a higher speed). These tests are all about getting a clear picture of the aero map of the car in as stable a condition as possible – by removing acceleration, you have time to gather substantial data.

"Sometimes teams will do this to correlate with windtunnel predictions, sometimes to evaluate specific aero parts by back-to-backing them, but usually with plenty of data-gathering sensors. If you added acceleration into the mix, you would get a huge number of snapshots of the car at different speeds and never see the aero map in its most stable form."

14:53 Liuzzi is currently 12th quickest in his HRT and clocks an improvement with a lap of 1m28.445s.

14:54 Kobayashi moves up a place to seventh fastest with a 1m25.059s lap.

14:56 Alonso kicked off his current run with a 1m24.449s. 10 laps later his pace is edging in to the 1m28s.

14:57 Liuzzi improves again on his first day with HRT. He's now 11th fastest with a best of 1m27.044s.

14:57 Rosberg is in and it's a racing stop for Mercedes as the team's second full-distance simulation in as many days continues.

14:59 A check of the weather with just over an hour remaining: It's pretty overcast now, with quite a lot of high-level cloud overhead.

15:00 There's no chance of rain before the sesssion ends, although AUTOSPORT Live's weather man @radarguruf1 forecasts some showers this evening

15:02 Rosberg kicks off the third stint of his race distance with a 1m30.941s lap.

15:03 Alonso is also heading out in the Ferrari. This is the Spaniard's last day here, with Felipe Massa taking over tomorrow.

15:08 Button pits after a run of 12 flying laps that started in the mid 1m29s and ended around two seconds slower.

15:09 Alonso is on the tail of Barrichello's Williams and lines up a move down the long pit straight and into Turn 1.

15:11 Kobayashi moves up to third quickest with a 1m24.243s in his Sauber.

15:12 Two laps on and Alonso is well clear of the Williams, lapping in the low 1m27s.

15:13 Alguersuari betters his time in 1m24.377s but remains fourth fastest.

15:14 It looks like the Red Bull has been fixed. Vettel is back aboard and heads out in the RB7.

15:17 Rosberg is nearing the end of his third stint, lapping in the 1m31s.

15:18 Robert Jan in the Netherlands says: First of all, I want to say great live feed, keep up the good work. I have a question: Do you know if Force India is driving with the new parts, like the adjustable rear wing and KERS?

AUTOSPORT.com features editor @TeamAnglais says:

"Force India is running with the adjustable rear wing, but it's difficult to tell from here if they are using it - or how often. Considering that it will only be used for qualifying and overtaking during the season, it is no use to use it during a lot of the race simulation work.

"And yes, all the teams apart from Lotus, Virgin and HRT are running KERS. But again, we don't know when they are using it."

15:20 Red Bull is picking up where it left off with Vettel's race simulation. The German is shown 24 laps to go on his pitboard.

15:22 Rosberg's times are now in the 1m32s. He's around 45 laps into his race distance and due another pitstop soon.

15:23 Vettel has resumed the third stint of his race after repairs to the RB7, lapping around the 1m28s mark.

15:27 Rosberg is going for a long third stint to his race. He's now 18 laps in, with times fading into the 1m33s.

15:27 Mercedes are out in the pitlane for Rosberg's final stop.

15:29 The German takes fresh rubber and is back underway.

15:31 We'll take a read on Rosberg's first flying lap, which should be somewhat faster with the fuel load in the Mercedes burning away, although we can't be sure if the tyres are brand new - or indeed what compound they are.

15:31 Alguersuari clocks a 1m23.519s and moves the Toro Rosso up to second fastest overall.

15:33 Red Bull is taking this race simulation very seriously and has both Christian Horner and Adrian Newey on the pitwall - just like a grand prix.

15:34 Vettel clocked a couple of laps in the late 1m27s earlier in this stint and 11 laps later he is in the mid 1m28s.

15:35 Heidfeld pits after improving his best to a 1m25.013s for eighth fastest in the Renault, which has been notably more reliable today.

15:37 Other than Vettel and Rosberg on race sims, Alonso and Barrichello are also lapping.

15:37 The Williams has completed a couple of long runs this afternoon, with Barrichello starting his latest outing with a time of 1m28.399s.

15:38 Alonso makes it a two-three for Spain in the headline times with a 1m23.978s tour as he begins a run.

15:42 A couple of people asking how we know the planned laps remaining for certain drivers ...

Well that's very simple - we look out of the window as the teams hang the pitboards out. We've got a great view of the leading teams' crews and garages from high up in the commentary boxes.

15:43 But it doesn't account for changes in plan cropping up. Vettel was shown 8 laps to go in his race distance the last time by ...

15:44 But he's now in the pits and wheeled back into the Red Bull garage.

15:47 Let's have some more longer run analysis from @TeamAnglais

Ferrari, McLaren and Williams all ran for stints of 12 laps at some point this afternoon. No information on tyre compounds or excess fuel, so it's another round of guessing.

Alonso was easily the quickest of the trio, starting in the 24s and dropping to four seconds slower after 10 laps. The drop-off rate looks like it could be either a looked after super soft or a thrashed soft.

Button and Barrichello both began in the 29s, though the McLaren was able to hang around the 1m30.0s or lower mark for longer than the Williams. Button slipped into the 31s for the last three laps of his stint (2s slower than it started) while Barrichello was in the 32s for his last three (finishing 3s slower than his first laps).

Alonso
24.4, 25.2, 25.8, 26.2, 28.2, 27.6, 27.0, 27.4, 27.6, 27.9, 28.4, 28.8

Button
29.4, 28.8, 28.8, 29.4, 29.8, 29.7, 29.8, 30.1, 30.8, 31.0, 31.7, 31.7

Barrichello
29.6, 29.4, 30.5, 31.0, 30.1, 30.7, 30.9, 31.3, 31.5, 32.2, 32.0, 32.5

15:49 On track, Heidfeld improves with a 1m25.013s. He's eighth fastest in the Renault.

15:49 Looks like a quick fix for Vettel's Red Bull and he's off to try and finish this very disrupted race simulation.

15:51 The pit crew are out for Red Bull, switching tyres for Vettel's run to the flag.

15:53 Perhaps that's the end of Vettel's race simulation actually as the team are out again and seem to have resorted to pitstop practice.

15:53 Rosberg is also wrapping up his race distance with a series of visits to the Mercedes pit.

15:56 @TeamAnglais has been looking at some of the earlier laps in those race runs ...

Both Red Bull and Mercedes at least attempted full race simulations this afternoon. Their plans were somewhat scuppered by Paul di Resta spinning the Force India into the gravel at Turn 1.

Vettel then lost half an hour in the garage, but we can assume from the L63 on his pit board at the beginning that he was carrying a lot of fuel.

He started out in the 29s and was still within a second of that after 11 laps. A couple of laps later he dropped to a 1m32s and then pitted. Vettel resumed in the 28s and posted a low 1m29s on his seventh lap just before the red flag. He was only on his second lap after the session resumed when he came back to the pits and the car spent half an hour in the garage.

Vettel
29.8, 29.2, 29.2, 29.4, 29.9, 30.2, 29.9, 30.1, 30.4, 30.4, 30.7, 31.0, 31.4, 32.1, P
28.4, 28.4, 28.7, 28.6, 29.1, 30.0, 29.2, RF
29.8, P

Rosberg too seemed to be fat with fuel and started his run in the 32s. He was still there after 10 and pitted a lap later. The Mercedes was down to the 30s after his stop but the red flag came just four laps in.

Once restarted, Rosberg fell from the 31s to the 33s over the next 10 laps. He pitted again then started the next 18-lap stint in the high 30s, only losing just over a second 14 laps later, The times then tailed off on the last four laps before another pitstop. So the Mercedes at least began to show improved consistency, although at best it was more than a second slower than the Red Bull on a seemingly similar run.

Rosberg
32.4, 32.3, 31.9, 32.4, 32.2, 32.2, 32.1, 32.2, 34.2, 32.7, 33.8, P
30.1, 30.4, 30.8, 30.9, RF
31.7, 31.3, 31.6, 32.0, 32.3, 32.6, 32.4, 32.6, 33.5, 33.5, P
30.9, 30.9, 31.2, 31.2, 30.8, 30.9, 31.1, 31.3, 33.7, 31.5, 31.6, 32.6, 32.2, 32.1, 32.8, 32.8, 33.5, 35.0, P

15:57 Meanwhile, Barrichello is up to fourth quickest with a late 1m24.008s lap.

15:58 Red Bull has been checking its cooling again, with the RB7 held in the pitbox for a minute with its engine running.

15:59 The chequered flag is being readied at the start/finish line.

16:00 The flag is now out to close day two at the Circuit de Catalunya.

16:00 That's all from our live coverage for today, and we're off to the paddock to speak with the drivers.

16:01 Stick with AUTOSPORT for all the reaction and we'll be back with live coverage from 08:00 GMT tomorrow.