Formula 1
12
are moved to Thursday), and one free practice on Saturday. Additional drivers (commonly known as third drivers) are allowed to run on Fridays, but only two cars may be used per team, requiring a race driver to give up their seat. A Qualifying session is held after the last free practice session. This session determines the starting order for the race.
Qualifying
For much of the sport's history, qualifying sessions differed little from practice sessions; drivers would have an entire session in which to attempt to set their fastest time, sometimes within a limited number of attempts, with the grid order determined by each driver's best single lap, fastest (on pole position) to slowest. Grids were limited to the fastest 26 cars and drivers had to lap within 107% of the pole sitter's time to
qualify for the race. Other formats have included Friday pre-qualifying, and sessions in which each driver was allowed only one qualifying lap, run separately in a predetermined order.
The current qualifying system was adopted for the 2006 season. Known as "knock-out" qualifying, it is split into three periods (or rounds). In each period, drivers run qualifying laps to attempt to advance to the next period, running as many laps as they wish, with the slowest drivers being "knocked out" at the end of the period and their grid positions set, based on their best lap times. Cars are eliminated in this manner until 10 cars remain eligible to attempt to qualify for pole position in the third and final period. For each period, all previous times are reset, and only a driver's fastest lap in that period (barring infractions) counts. Under current rules, for all periods, any timed lap started before the chequered flag falls signalling the end of that period may be completed, and will count toward that driver's placement, even if they cross the finish line after the period has ended. In the first two periods, cars may run any tyre compound they wish, and drivers eliminated in these periods are allowed to change their choice of tyres prior to the race. Cars taking part in the final period, however, must start the race with the tyres used during their fastest lap (the exact same tyres, not just the same compound), barring changes in weather that require usage of wet-weather tyres. With refuelling not allowed during races from 2010, the final session is run with low-fuel configuration and the cars are refuelled after qualifying.
Nigel Mansell's Williams FW10 from 1985