Williams FW36 - Montreal brakes 08 June 2014
Montreal is the most difficult circuit on the calendar for brakes. Five big stops per lap mean that brake cooling is a major headache for all the teams. Everything is a compromise on an F1 car - use more airflow for brake cooling and you lose downforce, so it is all about getting the balance correct. Over the past few years developments in materials technology have meant that the carbon brake discs and pads will withstand more heat than before and in Canada they can see temperatures in excess of 1000 degrees Celsius. If you see excess black brake dust coming from the wheels, that is the discs and pads wearing and a sign that the car could be running into trouble. On the Williams there is a duct (top blue arrow) that goes over the top of the disc to take some of the air that is going into the main brake duct (blue arrows on the right) over to the outside of the brake calliper (small dotted blue arrows show path of airflow). It is very important to cool the calliper or else the hydraulic fluid inside the calliper will boil. If that happens the brake pedal will have excess travel and a very spongy feeling, which around Montreal - with speeds in excess of 330 km/h - is the very last thing you want.