A multi-wall blade comprising a trailing edge cooling system, the trailing edge cooling system comprising: a coolant feed ; a coolant collection passage ; a plurality of sets of outward legs configured to extend axially toward a trailing edge of the multi-wall blade and fluidly coupled to the coolant feed ; a plurality of sets of return legs configured to extend axially toward a leading edge of the multi-wall blade and fluidly coupled to the coolant collection passage ; and a connecting system for fluidly coupling the sets of outward legs and the sets of return legs ; wherein the sets of outward legs are radially offset from the sets of return legs along a radial axis of the multi-wall blade , wherein the coolant feed is fluidly coupled to a plurality of sets of outward legs , and wherein the coolant collection passage is fluidly coupled to a plurality of sets of return legs ; wherein each of the sets of outward and return legs comprises at least two radially spaced legs ; wherein the sets of outward and return legs are radially spaced in an alternating sequence along at least a portion of a radial length of the trailing edge ; and wherein a first outward leg in a given set of outward legs is fluidly coupled by the connecting system to a return leg in an adjacent set of return legs , the return leg in said adjacent set of return legs being radially adjacent to the first outward leg , and wherein a second outward leg in the given set of outward legs is fluidly coupled by the connecting system to a return leg in another adjacent set of return legs , the return leg in said another adjacent set of return legs being radially adjacent to the second outward leg . a coolant feed ; a coolant collection passage ; a plurality of sets of outward legs configured to extend axially toward a trailing edge of the multi-wall blade and fluidly coupled to the coolant feed ; a plurality of sets of return legs configured to extend axially toward a leading edge of the multi-wall blade and fluidly coupled to the coolant collection passage ; and a connecting system for fluidly coupling the sets of outward legs and the sets of return legs ; wherein the sets of outward legs are radially offset from the sets of return legs along a radial axis of the multi-wall blade , wherein the coolant feed is fluidly coupled to a plurality of sets of outward legs , and wherein the coolant collection passage is fluidly coupled to a plurality of sets of return legs ; wherein each of the sets of outward and return legs comprises at least two radially spaced legs ; wherein the sets of outward and return legs are radially spaced in an alternating sequence along at least a portion of a radial length of the trailing edge ; and wherein a first outward leg in a given set of outward legs is fluidly coupled by the connecting system to a return leg in an adjacent set of return legs , the return leg in said adjacent set of return legs being radially adjacent to the first outward leg , and wherein a second outward leg in the given set of outward legs is fluidly coupled by the connecting system to a return leg in another adjacent set of return legs , the return leg in said another adjacent set of return legs being radially adjacent to the second outward leg . <EOS>