Staring the race behind the safety car
In case it is judged that the normal starting method could be dangerous due to the effects of heavy rain or other factors, race control determines to start the race using safety car in consideration of safety.
In addition, the restart method after race is suspended by the red flag is also a starting the race behind the safety car.
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The safety car turns orange rotating light on
The signal to start the race behind the safety car is that the safety car at the lead of the grid turns orange rotating light on one minute before the formation lap.
In the normal start procedure, the safety car at the lead of the grid starts running 5 minutes before the start of the formation lap and reaches the end of the grid after running one lap of the course.
Therefore, in case the safety car stays at lead of the grid even though it is less than 5 minutes before the start of the formation lap, it is highly likely that start procedure could be starting the race behind the safety car.
No Formation Lap
In case of starting the race behind the safety car, formation lap is not performed. At the timing of the starting the safety car, and the race starts.
After the line of cars leaded by the safety car passes near the pit road exit, the signal at the pit road exit turns green, and car starting from the pit road could enter the course and join the end of the line of the cars.
After the race start, operation is the same as a normal safety car
After the race start, the operation regulations are the same as those for the safety car, but the restarting the race is determined based on the situations. It may lead by the safety car for many laps, or it may be restarted immediately.
In Formula 1, due to the regulations change in 2017, after the starting the race behind the safety car, the race is restarted by standing start.
Regulations of Safety Car Operation
2.10 SAFETY CAR PROCEDURES
STARTING THE RACE BEHIND THE SAFETY CAR
2.10.18 In exceptional circumstances, the race may be started behind the safety car. In this case, at any time before the one-minute signal, its orange lights will be turned on. This is the signal to the drivers that the race will be started behind the safety car. When the green lights are illuminated, the safety car will leave the grid with all cars following in grid order no more than 5 car lengths apart. There will be no formation lap and the race will start when the green lights are illuminated.
Overtaking, during the first lap only, is permitted if a car is delayed when leaving its grid position and cars behind cannot avoid passing it without unduly delaying the remainder of the field. In this case, drivers may only overtake to re-establish the original starting order.
Soon after the last car in line behind the safety car passes the end of the pit exit, the pit exit light will turn green; any car in the pit lane may then enter the track and join the line of cars behind the safety car.
Any driver who is delayed leaving the grid may not overtake another moving car if he was stationary after the remainder of the cars had crossed the Line, and must form up at the back of the line of cars behind the safety car.
If more than one driver is affected, they must form up at the back of the field in the order in which they left the grid.
A penalty will be imposed on any driver who, in the opinion of the Stewards, unnecessarily overtook another car during the first lap.
2.9.19 A safety car may be used as the official car for a rolling start in conformity with Article 8.3 of the Code; in this case, the Supplementary Regulations governing the start will apply to it until it resumes its safety car function after the start has been given.