An elongate hollow structure with a plurality of reinforcements arranged in a pattern and acting as spacers between a pair of skins. The skins are of resin impregnated wound filaments with reinforcing strips of facing preimpregnated wound filaments that crisscross at the spacing reinforcements, abutting...http://www.google.com/patents/US4278485?utm_source=gb-gplus-sharePatent US4278485 - Method of forming composite wound structure
