We are a bit limited when it comes to VFX for float planes, as the water interaction VFX stop working when the aircraft is at high speed, and the float contact points are skipping across the water surface. In this case the simvar “CONTACT POINT WATER DEPTH” reads 0. To get a nice rich water spray and wake at high speed, it needs to still be active when the float point is near the surface.
It would be very useful to have this simvar also read height above water, as we’d be able to enable the VFX from a slightly negative value (above the water surface).
Currently the only way to enable a VFX when the contact point is at or above the water surface is to use a delay when lifting off (but this doesn’t give any benefits when landing) or use aircraft above ground simvar, which varies with several +/- feet, making it impossible to use for precise activation.