Patent ID: 8460777

Claim:
A cored, balanced and symmetric composite structure, the composite structure from inboard to outboard comprising: a first layer of high modulus metal; a first fiber layer including a plurality of high modulus balanced and symmetric plies, each ply comprising at least one of carbon fiber and boron fiber, in a cyanate ester resin matrix, attached to the first fiber layer, the first fiber layer comprising both carbon fiber plies and boron fiber plies; a second layer of high modulus metal attached to the first fiber layer; a layer comprising a honeycomb composite core including one of aromatic polyamide fiber or carbon fiber as a woven fabric and attached to the second layer of high modulus metal; a third layer of high modulus metal attached to a second fiber layer and the layer comprising a honeycomb composite core; a second fiber layer, including a plurality of high modulus balanced and symmetric plies, each ply comprising at least one of carbon fiber and boron fiber, in a cyanate ester resin matrix; and a fourth layer of high modulus metal attached to the second fiber layer; wherein each of the first, second, third and fourth layers of high modulus metal comprises one of tantalum, tungsten, beryllium, and a free-cut FeNi alloy having a typical analysis of carbon 0.05%, silicon 0.35%, cobalt 0.20%, manganese 0.90%, nickel 36%, selenium 0.20%, and the balance iron.