In wet conditions they would need to make the wet tyres a bit bigger to raise the ride height - they already are bigger than the drys, but we're only talking a couple of mm.
The drivers were not worried about the grip, they were worried about the visibility, like less than 10 metres, and fair enough too. The lack of grip just compounds the problem as you wont see anything happening infront of you till the last minute, and the lack of grip means you cant take avoiding action. Infact you can see from Rosberg coming off that this is exactly what happened. Any dry race and Rosberg could have avoided Webbers trundling car. Incidentally I find it amazing that anyone on here can blame on Webber! The stewards and commentators (who know a hell of alot more than anyone on here) certainly didnt blame him in any way shape or form!
Aquaplaning is not just to do with the cars ride height. There are two sorts of aqauplaning at work. Too much standing water and the tyres float on the top the same way a skimmed stone skips. The other (ride height related) is that the spray buffets the underside of the car to such a degree that it lifts the car up slightly. The water does not need to be deep for this to happen, there just needs to be enough spray.
I would imagine it's much more frequently the former, that the tyres simply cannot clear the volume of water away fast enough. The full wet tyre is incredible at clearing water, but I'd be astonished if it can fling up so much water that it actually lifts the front of the car (with all its aero downforce) before the tyre itself starts to aquaplane.
The plank runs very low to the floor so that might act like a keel, but I can't see water spray lifting both the car's weight and the downforce - we're talking about a couple of tonnes.
In very wet conditions the plank can indeed 'float' on standing water - liquids are incompressible, so if the water is deep enough it doesn't matter how much downforce the car has - if the floor of the car is lifted off the track then you will lose all your grip. Instantly.
Spray under the car isn't an issue, as the spray (effectively a coarse vapour) is compressible.
And whilst the tyres can clear a LOT of water, the cars are traveling quite fast - sometimes being able to fill a bath in 3 seconds isn't enough clearance.
The end of the race reminded of the last round of the british champs last year
Basically what happened is light was fading, and if the race was cancelled due to light the leading driver would be crowned championship. So the leading team put in a load of protests and as a consequence the race would be delayed and he'd be champion.
It was getting dark but the officials said "your racing" and we have pretty much zero commercial interests. The 2nd place driver had to play tactics to slow up the driver behind so he'd lose places etc... blahhh to gain championship.
Anyway... best race ever! Literally sparks flying off karts at night, with no lighting at all.. freakin' crazy
also sometimes you can't get enough grip to get to the speed where the downforce will push you through the water layer, bit of a catch 22 same as when you're tyres go cold / soft and you can't get the grip to push them hard enough to warm them up
That makes more sense, although I'm sure the tyres also would be at least at the point at which they start to aqua-plane if you ran the car through a puddle deep enough to cause the floor to skip across the surface. I suppose the lower the speed the more likely the tyres are to clear that volume of water.