[QB] tire size - the size and shape of a tire's contact patch has a direct influence on the probability of a hydroplane. The wider the contact patch is relative to its length, the higher the speed required to support hydroplaning.
[QB]
That's true.. sorta. Let's take this to extremes to see what I think is much more important.
If you had a bicycle tire on your car.. basically 1" wide, you'd never for any reasonable speed (sub 150mph) hydroplane. The simple weight of the car plus the fact that the tire will work like a knife will stop that from happening.
If you were to put balloons.. say 14" wide on your car, you'll hydro-plane that much faster. Which seemingly contradicts that quote.
You'll push that much more water in front of your tire to hydroplane with, becaue the contact patch's difference in cross sectional area creates less PSI for the water to carry the car.
Say the car weighs 4000 lbs. for arguments sake. If your contact patch is say 25 square inches, you have 4 of them(tires ya know). You'd need to have 40psi of water underneath your tires to support your car.
If your contact patch is say half that, you'd need 80psi of water underneath your tires to support the car. The chances of accumulating that pressure under the car with a narrower.. ie smaller contact patch is harder to accomplish and therefore takes a progressively higher speed to create that psi.
However if the contact patch was like a paddle, it would perform exactly like the bicycle wheel, cutting through the water instead. Provided that breaks in the tread are provided for the water to pass through. You could just as easily build up as much of a wave front before the tire with a wide but short patch that may create enough water to supply the necessary psi, but it's harder to do so it will plane before the bicycle tire but a lot more speed is required than the a wide and long patch area.
The area of the contact patch is what's key here, not really the width.
