I am considering scratch building a .40 nitro powered twin.

I am looking to build a relativity fast aircraft, so I need a fairly light and rigid structure.

I would like to build out of sheet foam insulation. I was planning a wire cut wing with a square CF full length spar.

Tail will be sheet balsa, foam on a CF rod.

My question is what sort of build, covering, reinforcement method can be used to ensure that the wing and fuselage do not flutter under the anticipated high speed?

Can monocoat be used to stiffen the structure?

Thanks,

Dave