Patent ID: 7963039

Claim:
A method of constructing a mandrel for fabrication of a monolithic composite nacelle comprising the steps of: fabricating a first outer section, a center section and a second outer section of the mandrel by forming an egg crate structure by welding together egg crate sections; machining said egg crate structure to a desired contour; stretch forming a metallic skin over said egg crate structure; attaching said metallic skin to said egg crate structure by welding; subjecting the egg crate structure to an anneal process; and machining the exterior surface of the metallic skin to the proper contour; assembling the center section between the first outer section and the second outer section; attaching a nozzle section adjacent to the first outer section, the center section and the second outer section; and machining the first outer section, center section, second outer section and nozzle section to form the mandrel.