Jenson Button was fastest in the first practice session at Abu Dhabi.
The two McLaren drivers had been quickest towards the end of the session before they were split by Mark Webber.
Hamilton led the early running as he went out on Pirelli’s new development rubber.
The two Red Bulls took over at the top of the times shortly afterwards, Mark Webber briefly leading Sebastian Vettel.
It was a scrappy session for the Ferrari drivers, both of which had spins. Felipe Massa lost the car turning into turn one, spinning off at speed.
Fernando Alonso spun at turn five and had several other off-track moments in his Ferrari.
The pair improved to fifth and sixth late on the session, also using Pirelli’s new development tyre.
Romain Grosjean was faster than his team mate but Vitaly Petrov had to abandon his car at the end of the session as sparks began coming from the car’s exhaust.
Robert Wickens, making his first appearance in an F1 practice session, was the slowest of the drivers to set at time.
Rubens Barrichello was unable to set a time, pulling over early in the session with engine failure.
2011 Abu Dhabi Grand Prix