A hydraulic blocking actuator comprising: a stator housing having a bore disposed axially therethrough; a first static piston assembly and a second static piston assembly, each static piston assembly having an outer longitudinal peripheral surface adapted to contact an inner wall of a portion of the stator housing, each static piston assembly including: two interior partial cylindrical surfaces, a single radial inwardly disposed vane positioned between the two interior partial cylindrical surfaces, and two radial inwardly disposed half vanes positioned at the distal ends of the two interior partial cylindrical surfaces, wherein the first static piston assembly and the second static piston assembly are disposed with one of the half vanes of the first static piston assembly adjacent longitudinally to one of the half vanes of the second static piston assembly and the other half vane of the first static piston assembly adjacent longitudinally to the other half vane of the second static piston assembly, and wherein each of the single vane and the half vanes has a inwardly disposed peripheral longitudinal face and a first peripheral lateral face and a second peripheral lateral face; at least two continuous seal grooves, each of said seal grooves disposed in a pathway along the peripheral longitudinal face and the first and second peripheral lateral faces of the single vane and the peripheral longitudinal face and the first and second peripheral lateral faces of one of the half vanes; a continuous seal disposed in each of the at least two continuous seal grooves; and a rotor adapted to be received in the bore of the housing. a stator housing having a bore disposed axially therethrough; a first static piston assembly and a second static piston assembly, each static piston assembly having an outer longitudinal peripheral surface adapted to contact an inner wall of a portion of the stator housing, each static piston assembly including: two interior partial cylindrical surfaces, a single radial inwardly disposed vane positioned between the two interior partial cylindrical surfaces, and two radial inwardly disposed half vanes positioned at the distal ends of the two interior partial cylindrical surfaces, wherein the first static piston assembly and the second static piston assembly are disposed with one of the half vanes of the first static piston assembly adjacent longitudinally to one of the half vanes of the second static piston assembly and the other half vane of the first static piston assembly adjacent longitudinally to the other half vane of the second static piston assembly, and wherein each of the single vane and the half vanes has a inwardly disposed peripheral longitudinal face and a first peripheral lateral face and a second peripheral lateral face; two interior partial cylindrical surfaces, a single radial inwardly disposed vane positioned between the two interior partial cylindrical surfaces, and two radial inwardly disposed half vanes positioned at the distal ends of the two interior partial cylindrical surfaces, wherein the first static piston assembly and the second static piston assembly are disposed with one of the half vanes of the first static piston assembly adjacent longitudinally to one of the half vanes of the second static piston assembly and the other half vane of the first static piston assembly adjacent longitudinally to the other half vane of the second static piston assembly, and wherein each of the single vane and the half vanes has a inwardly disposed peripheral longitudinal face and a first peripheral lateral face and a second peripheral lateral face; at least two continuous seal grooves, each of said seal grooves disposed in a pathway along the peripheral longitudinal face and the first and second peripheral lateral faces of the single vane and the peripheral longitudinal face and the first and second peripheral lateral faces of one of the half vanes; a continuous seal disposed in each of the at least two continuous seal grooves; and a rotor adapted to be received in the bore of the housing.