Ahead of today's opening free practice session, the air temperature is 26 degrees C, while the track temperature is 28 degrees. It is bright and sunny.

First off, of the reserve drivers, only Sakon Yamamoto is in action this morning, replacing Bruno Senna, having found an unspecified defect in the chassis he used in Monaco, Vettel comes to Turkey with 'Randy Mandy' having consigned 'Luscious Liz' to the scrapheap, or at the very least the Hall of Fame back at the team's HQ.

The Milton Keynes outfit is running its own version of the F-duct this weekend, while a number of other teams are introducing new components ahead of the long, long summer.

While Lotus, who are already working on their 2011 car, has a number of new components, most noticeably a new rear wing, McLaren has a revised front wing, including new endplates, while the Ferraris are wearing special logos to mark their eight hundredth Grand Prix.

Tyre compounds this weekend are hard (prime) and soft (option).

The lights go green and Liuzzi, Trulli, Kovalainen, Buemi, Alguersuari, Glock and Petrov lead the way.

Eight minutes into the session, all be Webber have been out. Surprisingly, ten minutes into the session, Schumacher is the first driver to come out for a second run. Indeed, moments later, Webber heads down the pitlane.

Over the course of the next ten minutes or so, various drivers come out for second installation laps, including Nico Rosberg and Vettel. However, as the Germans head back to the pits, it is Yamamoto who posts the first time of the day, the Hispania test driver crossing the line at 37.620.

Thirty minutes into the session, with Yamamoto having improved to 37.082, Trulli - who gets a little out of shape in the notorious Turn 8 - posts 34.793, despite the 'wobble'. Moments later, Alguersuari goes quickest with a 33.402 ahead of Kovalainen (33.966).

Alguersuari improves with a 32.670 as Trulli goes quickest in the first sector, eventually crossing the timing beam at 33.391. While Alguersuari improves with a 32.409, it is Kovalainen (32.357) who goes quickest.

Chandhok is crawling around the track, "I have a problem, it won't go," he tells his crew. As his crew tell him to "box", the Indian responds, "I'm trying to get back". Which he duly does.

Approaching half-time, and with only four names on the timesheets, Vettel and Schumacher leave the pits. While the Mercedes driver heads back to the pits after yet another installation lap, Vettel goes quickest with a 31.718.

At half-time, it's: Vettel, Alguersuari, Kovalainen, Hulkenberg, Trulli, Barrichello and Yamamoto.

As Vettel improvers with a 30.840, teammate Webber can only manage 37.481, which puts him ninth of the nine drivers who have posted times. Next time around the Australian goes third - behind Vettel and Petrov - with a 32.035.

After all the relative inactivity, suddenly the place is buzzing, with all the big guns on track. Kubica goes quickest (30.471), while Button goes third ahead of Hamilton and Massa.

A 29.672 sees Hamilton go quickest, only to be demoted by his teammate who crosses the line at 29.623. Schumacher goes third (30.356), ahead of Rosberg, Kubica, Vettel and Webber.

Rosberg makes a late decision to pit and then pulls off the asphalt immediately he enters the pitlane appearing to suffer a technical problem. However, moments later he gets going again and heads back to his pit.

Button consolidates his top spot with a 29.615, ahead of Hamilton, Schumacher, Vettel, Webber, Kubica, Petrov, Rosberg, Kobayashi and Massa. No times as yet from Glock, Sutil, Chandhok or di Grassi.

A 28.653 sees Hamilton re-take the top spot as Alonso seeks to improve on sixteenth (31.911). Next time around the Spaniard posts 30.866, thereby improving to tenth.

As Petrov improves to fifth (30.065), the McLaren are quickest through the main speed-trap, ahead of Liuzzi, Kubica, Vettel and Alonso.

With half-an-hour remaining, most drivers are focussing on longer runs, as Alonso improves to eighth with a 30.294. Elsewhere, Kubica runs very wide at Turn 1.