A non-contact seal assembly for a gas turbine engine, the non-contact seal assembly being configured to seal a gap between a stator and a rotor rotatable relative to the stator of the gas turbine engine comprising: a primary seal comprising a seal shoe, wherein the seal shoe comprises a plurality of seal shoe segments circumferentially spaced apart from each other, and wherein each seal shoe segment is configured to be movable in a radial direction; a mid-plate disposed forward to the primary seal; an aft secondary seal disposed forward to the mid-plate, wherein the aft secondary seal comprises a plurality of aft secondary seal segments circumferentially spaced apart from each other, and wherein each aft secondary seal segment is attached to each seal shoe segment and is configured to be movable in the radial direction along with each seal shoe segment, wherein in operation each aft secondary seal segment moves radially inwardly and outwardly with each seal show segment independently to adjacent aft secondary seal segments; a forward secondary seal disposed forward to the aft secondary seal; a seal carrier comprising an outer ring and a front plate and a back plate, wherein the front plate and the back plate extend circumferentially along the outer ring and radially from two axial sides of the outer ring forming a U-shape, and wherein the primary seal, the mid-plate, the aft secondary seal and the forward secondary seal are assembled in the U-shape; and a pin to hold the primary seal, the mid-plate, and the forward secondary seal to the seal carrier between the front plate and the back plate., wherein each aft secondary seal segment comprises at least a notch at an outer radial side, and wherein the notch is configured to receive the pin for accommodating a radial movement of each seal shoe segment. a primary seal comprising a seal shoe, wherein the seal shoe comprises a plurality of seal shoe segments circumferentially spaced apart from each other, and wherein each seal shoe segment is configured to be movable in a radial direction; a mid-plate disposed forward to the primary seal; an aft secondary seal disposed forward to the mid-plate, wherein the aft secondary seal comprises a plurality of aft secondary seal segments circumferentially spaced apart from each other, and wherein each aft secondary seal segment is attached to each seal shoe segment and is configured to be movable in the radial direction along with each seal shoe segment, wherein in operation each aft secondary seal segment moves radially inwardly and outwardly with each seal show segment independently to adjacent aft secondary seal segments; a forward secondary seal disposed forward to the aft secondary seal; a seal carrier comprising an outer ring and a front plate and a back plate, wherein the front plate and the back plate extend circumferentially along the outer ring and radially from two axial sides of the outer ring forming a U-shape, and wherein the primary seal, the mid-plate, the aft secondary seal and the forward secondary seal are assembled in the U-shape; and a pin to hold the primary seal, the mid-plate, and the forward secondary seal to the seal carrier between the front plate and the back plate., wherein each aft secondary seal segment comprises at least a notch at an outer radial side, and wherein the notch is configured to receive the pin for accommodating a radial movement of each seal shoe segment.