Modeling Water

Mark, theirs this brand new stuff out by woodland scenics, called, Water Effects, works and looks great!! looks like elmers glue when layed out, its kinda thick, but dries clear exactly like water!!
www.woodlandscenics.com

This article describes how to do the water.

http://www.digitaldioramas.com/2002/aug02/dd_geraths.htm

There are two ways you can add the aircraft.

1. Build a diorama tray/base deep enough to fit as is.
2. Cut the aircraft along a line that will be underwater, out of sight.

Whichever you choose, make sure you test the plastic and paint types to make sure the resin does no harm.
Resin layers of no more than 1/8 inch should not harm the model or the paint. Please test to make sure.
Good luck