In another thread this week, the topic of the Spencer Aircar came up. We discussed various aspects of the airplane's design, engine choices, and CG. The idea of building the Aircar as a pure flying boat (no landing gear), comparable to flying straight floats on regular plane, was mentioned. Combine that with picking and engine and what folks have had to do to get the CG right, it makes me wonder: how do you weigh a flying boat? I presume you'd have to put together some sort of fixture that the craft could rest on having scale locations with known distance from the datum. I'm presuming that a hanging weight wouldn't be an ideal situation.