When does an F1 car's rear light flash?

[Nickel]

maybe this is now clear to everyone except me
what does the red flashing light before braking mean ?

(a) 120 kW or some other kW of K motor action is absent
(b) 120 kW or some other kW of K generator action is present
(c) both of the above

Generator is charging from the rear wheels. Like "caution air brakes" on a truck.

Why would you do that in a situation other than braking? I'm not sure how or when people started associating lift - and - coast with k unit generating.

[hpras]

Maybe more like "Now accelerating as hard as I can with 160 less horsepower s the battery is flat" which in certain circumstance may actually be decelerating?

[jjn9128]

There appears to be a lot of different theories so I thought I'd look in the regulations for the reason - and there doesn't seem to be a rule on the light flashing in dry conditions. So it must be one of Formula 1's famous "gentlemen's agreements". My understanding is that it flashes when the car is no longer deploying electrical energy, i.e. the car is down 120kW so will not be accelerating at the same rate.

I did find that the rear light has to be flashing green if the driver doesn't have a super licence.

[Jolle]

I think the simple answer is: when, for any reason, the PU isn't giving full power. This might be from backing off the throttle, no more power from the ES, harvest mode, etc.

[PlatinumZealot]

maybe this is now clear to everyone except me
what does the red flashing light before braking mean ?

(a) 120 kW or some other kW of K motor action is absent
(b) 120 kW or some other kW of K generator action is present
(c) both of the above

Generator is charging from the rear wheels. Like "caution air brakes" on a truck.

Why would you do that in a situation other than braking? I'm not sure how or when people started associating lift - and - coast with k unit generating.

Ok. It was the reason why Alonso had that massive accident in Australia 2016. When the MGUK is charging the batteries and it has a malfunction the braking is irregular. Remember to conserve tyres, the drivers do not brake 100% at every braking zone. You could be braking at 80% power with a 60/40 brake balance, KERS malfunctions and all of sudden the rear braking increases to 55,45 and the rear tyres lock up - cars spins out and tank slaps another car.

[Jolle]

Generator is charging from the rear wheels. Like "caution air brakes" on a truck.

Why would you do that in a situation other than braking? I'm not sure how or when people started associating lift - and - coast with k unit generating.

Ok. It was the reason why Alonso had that massive accident in Australia 2016. When the MGUK is charging the batteries and it has a malfunction the braking is irregular. Remember to conserve tyres, the drivers do not brake 100% at every braking zone. You could be braking at 80% power with a 60/40 brake balance, KERS malfunctions and all of sudden the rear braking increases to 55,45 and the rear tyres lock up - cars spins out and tank slaps another car.

a wobble?

He just drove into Gutiérrez....

https://www.youtube.com/watch?v=vT17vWFkl_w

[everythingisawesome]

Ok - there's a lot of theories on here..

Flashing red lights on an F1 car occur when:

1. The car is harvesting energy into it's ERS (Energy Recovery System). That means it could be potentially slower in the corners. This acts as a warning for the driver following the car.
2. When visibility is poor (rain/fog)
3. During a pit stop.

[jjn9128]

Ok - there's a lot of theories on here..

Flashing red lights on an F1 car occur when:

1. The car is harvesting energy into it's ERS (Energy Recovery System). That means it could be potentially slower in the corners. This acts as a warning for the driver following the car.
2. When visibility is poor (rain/fog)
3. During a pit stop.

#1 is incorrect, it's not when it is harvesting, otherwise it would flash from application of the brakes all the way through the braking phase to corner apex. It flashes at the end (or even in the middle depending on the mapping) of straights to indicate a 'de-rate', i.e. the electric part of the hybrid is no longer supplying power to the car. It is a warning that the acceleration rate will slow because 120kW (~160bhp or ~1/6 of the total power) is missing. They are allowed to use a maximum of 4MJ of electrical energy per lap so where they use it is crucial, and that's better used to get the car up to speed.

4. When the car is travelling slowly, e.g. during FP when running aero rakes/floviz. I suppose this is linked to #3 as they probably have a limiter button/mode for constant speed during data collection.

[Tommy Cookers]

[quote=Nickel]
.......Why would you do that in a situation other than braking? I'm not sure how or when people started associating lift - and - coast with k unit generating.[/quote]

if people are 'lifting-and-coasting' (whatever L&C means) wouldn't they be crazy not to simultaneously K generate ?
at many of the 19 or so races where there's insufficient braking time for the K to generate 2 MJ/lap during braking

and now we must ask what does L&C actually mean - eg lift what and by how much ?

[NL_Fer]

A driver can use his right foot to:

1. Slightly lift, but keep throttle to deactivate the MGU-K so all power from the MGU-H is charged by the battery.
2. Full lift off the throttle, no power, save fuel