Montreal brake safety in the spotlight

Renault's director of engineering, Pat Symonds, explained: "The cooling of the brakes is very circuit-dependent. The brakes are cooled by forcing air through the brake ducts and blowing it both through the radial vents of the disc itself and also over the surface of the pads and discs.

"The amount of air is controlled by using different sized ducts and for a heavy braking circuit such as Montreal, we are forced to use some of the biggest ducts of the season. Moving from the smallest to the largest cooling ducts can cost 1.5 percent in aerodynamic efficiency, which represents a loss of 1kph in top speed."

Teams sailing too close to the wind can run out of brakes in the race. Last year, for example, Ferrari knew that Michael Schumacher had used half of his brake material in the first stint alone as he tried to stay with his brother, and had to adapt his driving throughout the rest of the race to make them last.

But, as McLaren's Martin Whitmarsh explained, it is wrong to blame the regulations for braking problems even though brake temperatures and hence wear have jumped due to extra grip from the tyres brought about by the Bridgestone/Michelin tyre war.

"The reality is that we can make 28mm discs last," Whitmarsh said. "Like all aspects of racing you are taking it to the limit, so inevitably here and Monza, which are heavy braking circuits, tend to be the option.

"If you made the discs 32mm, then we'd find ways to have better brakes for all the other circuits and when we got here we'd be in trouble again. I think the truth is that you could probably make them work at 20mm - you'd find a material which has less oxidisation or less wear and would last the race distance."