The main straight at Barcelonas Circuit de Catalunya, where last months Spanish Grand Prix was held, is one of the longest of the season, measuring just shy of a kilometre. A Formula One car can cover that distance in 11.5 seconds - a lifetime by Formula One standards. And when the driver hits the straight, hes already in fifth gear, so theres very little to do apart from keeping his foot flat on the throttle.
As Renaults Robert Kubica admits, its the perfect chance to take a breather and prepare for the lap ahead: In the car it feels like the main straight never ends, so its a good time to make adjustments on the steering wheel or talk to your engineer on the radio.
But what sort of adjustments can the drivers make, and what do all those colourful buttons and lights on the steering wheel actually do?
The most important things the driver can control from the cockpit are the differential settings, the brake balance and the front wing angle, explains chief race engineer, Alan Permane. As the fuel load comes down and the tyres lose performance, the driver can change all these parameters to improve the balance and handling of the car. Both Robert and team mate Vitaly (Petrov) have a pretty good feel for how these settings will affect the car, but we also offer advice over the radio based on what we see in the telemetry.
On average drivers will probably make tweaks to the differential every five laps or so, but there are some buttons that are used from corner to corner. In Shanghai during the Chinese Grand Prix, for example, Petrov was changing the multi-map setting on every lap to ensure optimum engine braking for Turn 14, the tricky hairpin at the end of the main straight. It has also become routine for drivers to adjust the brake balance from one corner to the next.
The wing button, introduced at the start of 2009, is also used regularly. At the press of a button, it allows the driver to manually adjust the angle of the front wing flap by up to six degrees while the car is out on track. Its a function thats especially useful during practice sessions, as Petrovs race engineer, Mark Slade, explains: The wing button is a quick and easy way to assess set-up options without having to bring the car back to the pits. We often send the car out with a base set-up and ask Vitaly if the car feels better with more or less wing.
While the drivers are familiar with the key functions of the wheel, there are some things they will only change if given the call over the radio. Buttons controlling the revs, for example, can be used to conserve the engine and will lower the revs at which the engine changes gear. Similarly the mix button adjusts the engine configuration if its necessary to save fuel.
The steering wheel is also the ideal place to display critical information relating to the race, especially lap times. We can put pretty much whatever information we want on the steering wheel display, explains Slade. But we try not to overload the driver with issues relating to the health of the car, such as temperatures and pressures. The most critical information they want is their lap times so we store their fastest time and the readout gives them a continuous update of their current lap relative to their best.
