Patent ID: 7735779

Claim:
A fuselage structure, comprising: an upper fuselage portion defined by a first cross-section including at least three different radii of curvature; a lower fuselage portion defined by a second cross-section including at least three different radii of curvature, wherein the first cross-section is different from the second cross-section; an integrated keel beam formed in the lower fuselage portion; wherein the integrated keel beam comprises: an outer layer of material; a core structure disposed on the outer layer; an inner layer of material formed on the core structure; wherein the core structure comprises: a first panelized portion formed of a plurality of stacked tapering layers extending from the inner layer toward the outer layer; a second panelized portion formed of a plurality of stacked tapering layers extending from the outer layer toward the inner layer; a first core member having a first wedge portion on a first side of the first and second panelized portions; a second core member having a second wedge portion on a second side of the first and second panelized portions; and the first and second wedge portions are disposed between corresponding tapered sections of the first and second panelized portions.