Casey Stoner dominated the opening practice session of the weekend at a chilly Silverstone.
As the MotoGP field worked from the British Grand Prix venue's new pit complex for the first time, the Australian took the top spot early on and maintained a healthy cushion over his rivals.
At one stage Stoner's Honda was 1.3 seconds clear of the field, and his eventual 2m03.748s lap put him 0.659s ahead of second-placed Marco Simoncelli (Gresini Honda), who gained 0.3s on Stoner with his last run.
Last year's Silverstone winner Jorge Lorenzo was third for Yamaha, a second off Stoner's pace.
Nicky Hayden was top Ducati rider in fourth, as his team-mate Valentino Rossi learned the circuit in low-key fashion and ended up only 12th. He had a brief excursion at Abbey early on but rejoined without drama.
Britain's hope Cal Crutchlow (Tech 3 Yamaha) got as high as second before other riders' late improvements edged him back to sixth, behind Honda's Andrea Dovizioso, and just ahead of works Yamaha rider Ben Spies.
Aspar Ducati's Hector Barbera was eighth, with the Suzuki of Alvaro Bautista and Randy de Puniet's Pramac Ducati completing the top 10. De Puniet's team-mate Loris Capirossi had the only accident of the morning, sliding to the ground under braking for Vale. He was unhurt.
In his first appearance on the bike since breaking his collarbone in Spain a week ago today, Tech 3's Colin Edwards managed 13 laps and brought up the rear of the field.
Pos Rider Team/Bike Time Gap 1. Casey Stoner Honda 2m03.748s 2. Marco Simoncelli Gresini Honda 2m04.407s + 0.659s 3. Jorge Lorenzo Yamaha 2m04.756s + 1.008s 4. Nicky Hayden Ducati 2m04.778s + 1.030s 5. Andrea Dovizioso Honda 2m04.910s + 1.162s 6. Cal Crutchlow Tech 3 Yamaha 2m05.007s + 1.259s 7. Ben Spies Yamaha 2m05.130s + 1.382s 8. Hector Barbera Aspar Ducati 2m06.158s + 2.410s 9. Alvaro Bautista Suzuki 2m06.274s + 2.526s 10. Randy de Puniet Pramac Ducati 2m06.573s + 2.825s 11. Karel Abraham Cardion Ducati 2m06.774s + 3.026s 12. Valentino Rossi Ducati 2m07.075s + 3.327s 13. Hiroshi Aoyama Gresini Honda 2m07.459s + 3.711s 14. Toni Elias LCR Honda 2m07.616s + 3.868s 15. Loris Capirossi Pramac Ducati 2m08.225s + 4.477s 16. Colin Edwards Tech 3 Yamaha 2m09.310s + 5.562s