Valencia winner Adrian Quaife-Hobbs kept his momentum rolling by topping a rain-affected first GP3 free practice session at Silverstone on Friday lunchtime.
Although the session started with a dry track, a rain shower swept across the circuit on the opening lap, setting the tone for a disrupted half-hour of tricky conditions. Lewis Williamson set the early pace, before being bettered by fellow Briton James Calado, then Antonio Felix da Costa and Rio Haryanto.
With half the session gone, Calado was fastest at the second split but then put all four wheels on the grass-crete exiting Stowe and spun back across the track, clattering the tire wall like Guido van der Garde had done in GP2 half an hour earlier. This promoted a long yellow flag while car was being recovered.
After the yellow flag was withdrawn, the rain started again, but Valtteri Bottas, Alexander Sims and Haryanto all squeezed in good laps in the brief weather window, taking it in turns to top the times.
A heavier rain shower with six minutes remaining sent many cars scurrying back to the pits, including Haryanto, but those who stayed out were rewarded with the best track conditions right at the end. Williamson briefly grabbed top spot again, before Quaife-Hobbs beat him by 0.378sec, which no one else could outdo. Haryanto stayed third, just ahead of Gabby Chaves, Mitch Evans, Bottas, Dean Smith and Sims.