On the face of it, the flashing red light on the back of every F1 car may only seem like a minor feature, but it is vitally important for the safety aspect of the sport.


Safety has become paramount in Formula One, particularly in the 21st century with the advancement of technology.

In the bad old days of the sport, it was common to have multiple fatalities per season and now deaths and even serious injuries are very, very rare.

Jules Bianchi is the only driver to have been killed as a direct result of a crash in F1 since the tragic loss of Ayrton Senna in 1994.

The flashing red light is all about safety and alerting drivers that a car is nearby, and it serves two purposes.

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Why is the flashing red light used during wet races?

Quite simply, the light is there to alert drivers behind that a car is in front of them, like in a road car.

Even light rain can be extremely difficult to drive in with all the spray flying up from the road as well as rain marks on the driver’s helmet visor. And, obviously, with cars being open cockpits, there are no windscreens to wipe.

Think about how challenging it can be to drive on a motorway in wet conditions doing 60-70mph. Then times that by nearly three and that is what the experience of wet weather driving in F1 is like.

Cars are so difficult to spot in front and the red light offers a hugely important visible aid to drivers to avoid massive accidents from potentially occurring.

What does the red light mean in clear conditions?

In general, the red light is used in dry conditions only in qualifying or practice sessions and is used to indicate a car is slowing down or coasting along towards the pit lane.

A car usually does this when it has completed a qualifying lap and is slowing down before returning to the pit lane. Conversely, it may be saving its tyres ready to attack a full-speed qualifying lap.

Cars also deploy the red light when they are using the Energy Recovery System (ERS).

This, in an incredibly complex manner, converts unused kinetic and thermal energy into extra power to use later in the lap. However, in order for this to work, the car will slow down and thus the red light will flash.

Does the light flash any other colour?

Very occasionally, there will be a green light on the back of an F1 car. This is to indicate there is a “rookie” driver who does not currently possess a full FIA Super Licence.

Drivers can race in F1 only if they are granted a Super Licence by the FIA (the sport’s governing body).

However, a driver is permitted to drive the car if they have met all the qualifications of a Super Licence but don’t yet have the licence – in the same way that someone who passes their driving test will not get hold of their driving licence straight away.

Alex Albon, currently driving for Williams, is a recent example of this and his car featured a green light when making his debut in the sport back in 2019.

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