Composite hollow blade and an associated method of forming the composite hollow blade are disclosed. The method includes forming a core by fabricating a grid core structure based on a plurality of design parameters, where the grid core includes a plurality of first reinforcing components disposed in a first curable matrix material. The method further includes forming an outer layer including a plurality of second reinforcing components disposed in a second curable matrix material. Further, the method includes coupling the core to the outer layer and curing the core and the outer layer to form the composite hollow blade.