Hamilton heads Button in Abu Dhabi GP Second Practice

Lewis Hamilton completed a Friday sweep for McLaren by setting the pace in the second free practice session in Abu Dhabi, ahead of his team-mate Jenson Button.

But while the McLaren men carried on serenely, Turn 1 claimed two world champions with both Sebastian Vettel and Fernando Alonso hitting the barriers during the session.

Alonso's accident was enough to call an early halt to his session, but he was third fastest ahead of Ferrari team-mate Felipe Massa, Mark Webber and Vettel.

Michael Schumacher, who once again ran off track more than once during the session, was seventh ahead of Adrian Sutil, Paul di Resta and Kamui Kobayashi.

A busy start to the session saw di Resta establish himself at the top of the times with a 1m42.550s, but only momentarily until Webber usurped him with a time 0.528s faster.

There followed a period of Red Bull dominance in the opening 15 minutes as Vettel then beat Webber's time, only for the Australian to respond instantly with a 1m40.723s. So it continued as Vettel produced a 1m40.514s; then Webber a 1m40.598s - 0.084s between them. Webber's lap times dropped off after that, but Vettel went faster still to record a 1m40.197s.

With quarter of an hour gone it was Vettel, Webber and di Resta's Force India team-mate Sutil – all having set their laps on the experimental soft tyres – ahead of Hamilton and Schumacher's Mercedes.

Alonso changed all that by going second fastest in the Ferrari, which seemed to be behaving better in the twilight conditions of FP2. Making the most of the new soft tyres he then improved to a 1m40.141s, putting him at the top of the pile for the first time in the weekend. By the time he had completed his run, Alonso had reduced that mark to 1m39.971s.

As the session moved into the halfway mark, Red Bull and McLaren began working on their long runs, not assisted it has to be said by a spin for Mark Webber at Turn 18. There appeared to be very little in it between the two teams.

With 40 minutes to go, McLaren bolted on the official 'Abu Dhabi' softs (as opposed to the experimental ones Pirelli has been testing on Friday) for the first time and instantly Hamilton moved to the top with a 1m39.586s. Team-mate Button's best attempt was a 1m39.785s – good enough for second.

Red Bull was also out on the option Pirellis by this time as well, and it was now that the first major drama of the session took place as Vettel crashed on a Friday for the fourth time this season. The German also thumped the barriers in Turkey, Canada and Japan earlier this year.

On this occasion he was lying fifth in the times when he turned in on the kerbs at Turn 1, lost the rear and slid sideways in to the TecPro barriers. Little obvious damage was done to the RB7 beyond a broken front wing. So little in fact that he was able to rejoin the session after the car was recovered.

The resulting yellow flags in the crash zone prompted a period of calm as most people headed for the pits.

But the circuit had been back to 'green' for no more than 10 minutes when drama number two occurred, and this time it was Alonso who had backed his Ferrari into Turn 1.

The Spaniard had done significantly more visible damage to his car than Vettel with a broken rear wing and rear suspension – his day's track action most definitely concluded.

All this left McLaren, Webber and the rest to concentrate on their heavy-fuel, soft-tyred race pace as the session moved into its last 20 minutes, but there no more significant changes to the order.