Ahead of today's opening practice session, the air temperature is 25 degrees C, while the track temperature is 35 degrees. It is warm... and it is going to get a whole lot warmer.

Tyres available this weekend are soft (prime) and supersoft (option).

For the first time at Hockenheim there are two DRS zones. The detection point of the first is 110m before T1, with the activation point 60m after T1. The second detection point is at the exit of T4, with the activation point 260m after T4.

The big news - at a time that events elsewhere in the world put F1 truly in perspective - is that none of the teams are running front to rear linked suspension systems (FRIC) this weekend, thereby avoiding the possibility of teams protesting one another. For now.

That said, some believe Red Bull could benefit more from the 'ban'.

Once again, there are a couple of reserve drivers on duty, most notably Susie Wolff who will be hoping to get a bit more mileage than he enjoyed at Silverstone. Elsewhere, Giedo Van der Garde is in the Sauber following his heavy crash in the final moments of last week's Silverstone test. They are replacing Bottas and Gutierrez respectively.

The lights go green and Wolff leads the way, followed by Vergne, Ericsson, Massa and Van der Garde.

Oh dear. Wolff has slowed to a crawl. "I have a problem with the upshift," she complains. The car is still moving, so she has drive. She is told to continue and try to get the car back. Elsewhere, suspect smoke pours from the back of Chilton's Marussia.

As Wolff slowly makes her way through the stadium section, all the other 21 drivers have been out for an installation lap.

Despite the availability of an extra set of tyres and near perfect condition, there is a period of total inactivity. If the FIA really wants to act on something...

Finally, an engine fires up and Ericsson heads down the pitlane, the Swede subsequently posting the first time of the weekend (1:28.480). Elsewhere, Williams reports Wolff's problem has been "resolved" and she will be out again soon.

Ericsson is joined by Caterham teammate Kobayashi who immediately goes quicker with a 24.466.

As more cars take to the track, Wolff posts 22.481 to go quickest, only to be leapfrogged by Magnussen in the McLaren (20.471).

After the lull it is now quite busy, suspension testing clearly on the agenda following the removal of the FRIC systems.

Having gone quickest in the first two sectors, Hamilton slows in order to find some space whilst teammate Rosberg reports "debris at Turn 6". The German subsequently locks up in front of a totally empty grandstand at T15.

"We have a problem with the water pump," Raikkonen is told, "slow down and come back to the pits."

As Button goes second (20.576) to make it a McLaren 1-2, both Mercedes drivers are having problems remaining on the black stuff, appearing to run wide in numerous corners.

A 20.337s sees Rosberg take the top spot, while Vettel goes fourth ahead of Alonso. Hamilton, currently 16th (22.688), goes quickest in the first two sectors again before once again aborting the lap.

With Chilton and Raikkonen still to post times, Vettel goes quickest with a 20.295.

As the opening half-hour comes to an end most drivers return to the pits to hand back their 'free' tyres.

Current order is: Vettel, Rosberg, Magnussen, Ricciardo, Alonso, Button, Sutil, Vergne, Massa and Perez.