Morning: Lewis Hamilton has been the man who has done more laps this morning. After a first contact, the Englishman has made four lengthy stints, lowering his times every time he went back to the track. On the opposite side is Kimi Räkkönen, who could not make any time, since we have not seen the Lotus anymore after the installation lap, presumably because of problems with the gearbox.
Williams has also made a handful of laps, the majority of them have been in short stints, except one long stint in which Valteri Bottas went through boxes all the time. In Williams have said this morning that they have focused on aerodynamic tests and checks on the car.
Fernando Alonso was the second driver who has done fewer turns since, before 12 in the morning, the engine has had some problems, according to Ferrari, because it had reached the end of his life (that was the same engine used in Jerez).
The best time of the morning has been done by Sebastian Vettel, again, and with the medium compound. The Red Bull has approached the best time in Q3 of last season, which is sure to be overtaken soon.
McLaren has done sets of 6 or 7 laps the whole morning. In the last, Sergio Perez has used the soft compound, taking the third fastest time.
Caterham have carried out a similar program. Marussia have done lots of verifications, continuously entering to boxes and not marking many times. Force India hasn’t focused on the times as well, but they have done many laps in and out of box too, probably doing aerodynamic testing, and have not done any time until late in the morning, in very short runs. Sauber’s session was identical to Force India.

Afternoon:

Most teams have done long stints, testing adjustments to the car and working to obtain data on the behavior of the tires.
Mercedes completed 121 laps in total, but we have seen that the times of Lewis Hamilton started being very fast, but quickly collapsed. The stints of Sergio Perez started with much slower times, but were much more consistent, which suggests that teams have proven quite different things and, as usual, the times that we see do not allow comparisons between teams.
Ferrari has finally fixed their problems and come out when there were two hours, making two long runs, the two similar: beginning in 1:23.9, then 1:24 to get to do high 1:27 s and 1:28 s, therefore again this cannot be used to draw many conclusions, but certainly the teams have gained a lot of information, very important for the use of the tyres.
At Red Bull, the afternoon was worse than the morning, being the RB9 the causer of the only red flag of the day, when there were 50 minutes. It seemed that Sebastian Vettel was doing a race simulation, when the car has stopped at the end of the main straight, just after making a pit stop.
In contrast, Lotus have rolled for nearly an hour, times also fell a lot every lap made Kimi.
Williams has also made a couple of long runs, with times that at first glance appear to be far below the top teams, but just remember that it was the second day of the FW35 on track.
Force India have not done many laps, and were enclosed in boxes although the session had an hour and a half to finish. But they have just surpassed Lotus in relation to laps done.
Marussia has been testing all day. They haven’t practically done times, but have come to complete 67 laps.
Toro Rosso has made a few runs of 5 to 8 laps, surely proving adjustments to the car, and Caterham were the ones who, after Mercedes, have worked the most. After completing 102 laps and some quite long stints, they were more consistent with the times of the whole grid, reaching 11 consecutive laps performing at 1:31, we do not know under what conditions.
The only thing we can say seeing the stints of the top teams, is that it seems Pirelli tires become worn soon, we’ll see if this is confirmed the next days.

Time table:

Pos Driver Team Laps Time
1 S. Pérez McLaren 97 1:21.848
2 S. Vettel Red Bull 84 1:22.197
3 K. Räikkönen Lotus 43 1:22.697
4 L. Hamilton Mercedes 121 1:22.726
5 F. Alonso Ferrari 76 1:23.247
6 V. Bottas Williams 98 1:23.561
7 D. Ricciardo Toro Rosso 70 1:23.718
8 P. di Resta Force India 62 1:23.971
9 N. Hulkenberg Sauber 88 1:24.205
10 M. Chilton Marussi 67 1:25.115
11 C. Pic Caterham 102 1:26.243