F1: DRS rethink planned to turn Turkey shoot into Spanish glee.

Instead of the DRS zone being on a short straight leading to a tight s-bend, as in Turkey, now the calculation point will be shortly before the main straight - and DRS will be available all the way down the start-finish straight. Aerodynamically, DRS works by removing, temporarily, downforce and therefore drag. Low downforce equals higher speeds: but only in a straight line. Mechanically, DRS works by lifting the topmost rear wing so that it is horizontal(ish) instead of set at a steep angle which pushes the car down.

When DRS is activated, the nothing happens for a fraction of a second - then the vortex created by the usual rear-wing setting fills in with air that shoots through rather than over the rear-wing assembly. That means the car is not sucked backwards by its own aero-vacuum.

The other side of the equation is that when the DRS is turned off, the car destabilises for a fraction of a second before the airflow is restored over the rear wing, now in its "down" position.

DRS is turned off when the driver touches the brakes. The later he brakes into a corner, the deeper into that corner it is before the car restabilises.

The rules say that DRS may be used only within a specified zone and only if the car is less than one second behind the car in front.

In Turkey, that one second was negated because of the placing of the gap measurement point and the placing of the DRS zone. The car in front was able to leave a series of corners and gain a sufficient advantage before the DRS zone that the added speed was often not sufficient to enable the chasing car to catch up. If he did, he did not have time to escape and build up more than one second before places were swapped again.

In Spain, however, the combination of the placing of the gap measurement will mean that cars remain broadly similar distance apart at the start of the DRS zone. Add in traditional slipstreaming down the long main straight and the boost from KERS and we may be in for some derring-do at the first corner. And lots of cars in the gravel.