Darryn,
What I was talking about is slightly different, I think what you are describing is a sandwhich construction, where a composite skin is sandwhiched with an Al skin or honeycomb.
I was talking about a aluminium that has carbon fibres impregnated into it.
In this case you get a composite that is nearly as light as Al but as stiff as steel.
Gareth
www.fourhulls.com