@Trenchfeet :
The whole thing is going way above my head, as I know very little about add-ons, but couldn't you use the in-game water-wash scripts by defining your plane as a boat when its height is under, say, 2 meters ? There's got to be a way to use an eventhandler (I'm thinking about "engine" here) that would launch a height-check script that would itself trigger off the in-game scripts.
I hope I'm making sense here : your plane is just BRILLIANT, but it's true it amazed me not to see any water-particles when floating, so I hope someone will find an answer.
I'm going to try to script the water-fx themselves, and combine them with an eventhandler, but I have little time this week, so hopefully you'll have solved the topic by the time I come up with something decent...
Anyway, your JU-52 ranks high, real high. Congratulations.