Stiffened structural components, particularly integrally stiffened light weight shell structures, produced by molding astiffening member, preferably formed of a graphite-epoxy composition and having a so-called isogrid rib stiffening configuration, to a partially cured (B-stage) condition, injecting...http://www.google.com.au/patents/US4086378?utm_source=gb-gplus-sharePatent US4086378 - Stiffened composite structural member and method of fabrication
