A turbofan gas turbine engine comprising a fan adapted to be rotated about an axis to accelerate air, an engine core coupled to the fan to drive rotation of the fan, the engine core including a compressor, a combustor, and a turbine, an annular frame including an inner wall that extends around the engine core and an outer wall that extends around the inner wall, the inner wall and the outer wall cooperating to define a bypass duct radially there between in fluid communication with the fan to receive bypass air accelerated by the fan, and including a strut that extends from the outer wall through the bypass duct to the inner wall of the annular frame, an inlet guide vane assembly including a bypass inlet vane ring arranged between the fan and the bypass duct of the annular frame to redirect air moving from the fan to the bypass duct, a core inlet vane ring arranged between the fan and the compressor of the engine core to redirect air moving from the fan to the compressor, and a splitter coupled radially between the bypass inlet vane ring and the core inlet vane ring, and a cleaning system configured to conduct a cleaning agent from a supply radially through the bypass duct to the engine core; wherein the cleaning system includes: (i) a supply connector adapted to be fluidly coupled to the supply and receive the cleaning agent, (ii) a conduit that extends from the supply connector perpendicular to the axis between the outer wall of the annular frame and the inner wall of the annular frame and is arranged in the strut so that the conduit is shielded from air accelerated from the fan passing through the bypass duct, and (iii) a transfer tube that extends axially within the splitter from the conduit to an injector mounted in the core inlet vane ring, said injector formed to include an aperture arranged to conduct the cleaning agent into the compressor of the engine core. a fan adapted to be rotated about an axis to accelerate air, an engine core coupled to the fan to drive rotation of the fan, the engine core including a compressor, a combustor, and a turbine, an annular frame including an inner wall that extends around the engine core and an outer wall that extends around the inner wall, the inner wall and the outer wall cooperating to define a bypass duct radially there between in fluid communication with the fan to receive bypass air accelerated by the fan, and including a strut that extends from the outer wall through the bypass duct to the inner wall of the annular frame, an inlet guide vane assembly including a bypass inlet vane ring arranged between the fan and the bypass duct of the annular frame to redirect air moving from the fan to the bypass duct, a core inlet vane ring arranged between the fan and the compressor of the engine core to redirect air moving from the fan to the compressor, and a splitter coupled radially between the bypass inlet vane ring and the core inlet vane ring, and a cleaning system configured to conduct a cleaning agent from a supply radially through the bypass duct to the engine core; wherein the cleaning system includes: (i) a supply connector adapted to be fluidly coupled to the supply and receive the cleaning agent, (ii) a conduit that extends from the supply connector perpendicular to the axis between the outer wall of the annular frame and the inner wall of the annular frame and is arranged in the strut so that the conduit is shielded from air accelerated from the fan passing through the bypass duct, and (iii) a transfer tube that extends axially within the splitter from the conduit to an injector mounted in the core inlet vane ring, said injector formed to include an aperture arranged to conduct the cleaning agent into the compressor of the engine core. (i) a supply connector adapted to be fluidly coupled to the supply and receive the cleaning agent, (ii) a conduit that extends from the supply connector perpendicular to the axis between the outer wall of the annular frame and the inner wall of the annular frame and is arranged in the strut so that the conduit is shielded from air accelerated from the fan passing through the bypass duct, and (iii) a transfer tube that extends axially within the splitter from the conduit to an injector mounted in the core inlet vane ring, said injector formed to include an aperture arranged to conduct the cleaning agent into the compressor of the engine core.