A method of fabricating a thermoplastic composite tubular structure provides a mandrel of a soluble, expandable material. The method overbraids the mandrel with a continuous fiber thermoplastic composite material to form an overbraided mandrel. The method installs the overbraided mandrel into a matched tooling assembly. The method heats in a heating apparatus the matched tooling assembly with the installed overbraided mandrel at a specified heating profile in order to consolidate the thermoplastic composite material and form a thermoplastic composite tubular structure. The method cools the matched tooling assembly with the formed thermoplastic composite tubular structure at a specified cooling profile. The method removes the formed thermoplastic composite tubular structure from the matched tooling assembly. The method solubilizes the mandrel to permanently remove the mandrel from the formed thermoplastic composite tubular structure.