Why Do F1 Cars Have Flashing Red Lights?

Formula One has been with us since 1950 and since that time we have seen many changes. In the last twenty years, the majority of these changes have focused around safety and efficiency and it is related to these areas that this question can be answered.

The flashing red lights at the rear of an F1 car are in place to increase the safety of drivers during a race. The flashing light on the car enables other drivers to see it during adverse weather conditions and also indicates harvesting is occurring.

What is the purpose of the red flashing light on F1 cars?

The red flashing light at the rear of an F1 is clearly visible and has been noticed by fans since its conception in 2014 (although the original basic light was first introduced in 1972). The fact that it has been noticed more recently is exactly its point.

The light was introduced to serve two purposes:

Wet weather visibility

You may have noticed that when driving on a road in torrential rain, visibility becomes restricted and everyone slows down (well, the majority of drivers!). The casual driver like you or me has the advantage of windscreen wipers and other road-users that will most likely have their lights on and will also be driving at slower speeds.

Imagine doing the same but without windscreen wipers – it quickly becomes incredibly difficult to see what’s going on in front of you. Now imagine the same but traveling at speeds close to 200 mph, racing within feet of other cars and those other cars not having any kind of rear lights.

The spray that emanates from an F1 car in front of you on track makes it almost impossible to see what’s ahead of you. You may have noticed that in these conditions, the driver behind will weave onto a different line – this is purely so they can try and see what’s going on in front of them!

The introduction of a flashing red light on the rear of F1 cars during races helps at least one of these points. It increases the visibility of other cars during a race and allows you to see the car in front during bad weather conditions. Well, you might not see their actual car but you have a better chance of seeing their flashing light!

Energy Harvesting

The flashing red lights on the rear of F1 cars also occur when energy harvesting is taking place. Harvesting is part of the ERS (Energy Recovery System) that allows for the conversion of kinetic energy (that is generated under braking) and heat energy (from exhaust gasses) into electrical energy. These two processes are known as MGU-K and MGU-H (Motor Generator Unit – Kinetic and Motor Generator Unit – Heat).

When the energy transference is taking place the red light will flash and this warns other drivers that the car may be running a little slower than usual (caused by the ERS system.

F1 car with rear lights

Is the flashing red light indicative of braking?

A common misconception is that the red light on the rear of F1 cars flashes when they brake, in a manner not dissimilar to conventional cars. This is not the case and F1 cars do not have brake lights.

Brake lights on a car as quick as in Formula One would serve no purpose. Firstly, if you are close behind a car traveling at near 200 mph down a straight then you will know the braking point for your style of driving and for the car you’re driving in. It serves no purpose to be informed when the car in front is braking.

To give another example, the car in front might be on a totally different tyre strategy – one driver may have fresh tyres with loads of grip (able to stop and turn better) and the person in front of them might have old tyres with less grip (and therefore unable to corner at such high speeds).

You see, there are so many variables that can affect the braking point of an F1 car (although broadly speaking there’s not a lot in it) that it serves no purpose in having them!

Are there any other lights on an F1 car?

For wet weather conditions, Formula 1 cars also have two additional lights that shine red – these can be found on the back of the rear wing. They’re quite discreet so you might not notice them until they’re on!

What would happen if F1 cars didn’t have the rear lights?

If Formula One cars didn’t have these red lights then it would increase the chances of incidents during a race (or another part of the race weekend, such as qualifying).

An example would be two cars racing fast around a bend, the one in front having ERS active and the one behind, not. The one without ERS being active would be faster (potentially) than the one with ERS active. Without the flashing red lights, the driver behind would be expecting the car in front to be traveling at a certain speed and could drive into the back of it, causing an accident.

Other interesting information about the F1 rear lights

These lights have to be bright enough for other racers to be able to see them in extreme conditions, so they increased the power of the original light from 15W to 21W in 1983.

Drivers sit very low to the ground in F1 cars, therefore the lights need to be positioned in a place where the driver can see them at approximately eye level, this is why the rear red lights are positioned just 30cm from the ground.

One other interesting fact is that the rear lights can also be green. This is to indicate that the driver is a novice and they don’t as yet own a Super License. This license is mandatory to race in Formula 1 and not easy to get!

We often see changes that are first implemented onto F1 cars then appear in road cars. This is the case with these rear lights as they have since been introduced on Ferrari road cars, such as the 488 and Ferrari La Ferrari, see the image below from a 488 – the lights are between the exhaust.

Ferrari 488 rear