A stator vane for a gas turbine engine comprising: an airfoil extending radially from a first side of a platform, a pocket (90; 190) provided in the platform on a second side opposite the airfoil, forward and aft rails (100,102) extending from the second side of the platform, one of the forward and aft rails (100,102) including a radial surface (118;218); a cooling passage extending through the airfoil to the second side; and an impingement plate (108;208) secured to the platform over the pocket (90;190), the impingement plate (108;208) including a radial flange (120;220) engaging the radial surface (118;218), and an opening aligned with the cooling passage to provide fluid communication therebetween, wherein the pocket is circumscribed by a perimeter, the perimeter provided by the forward and aft rails (100,102) and spaced apart lateral walls (104,106) joining the forward and aft rails (100,102), wherein the second side includes a ridge circumscribing the cooling passage and engaging the impingement plate near the opening,wherein the impingement plate (108;208) is unsupported immediately beneath the radial flange (120;220) in the radial direction and includes a cooling wall that provides the opening, and the cooling wall includes multiple cooling holes facing the second side; characterised in that: the impingement plate is supported by at least one pedestal near the radial flange in the radial direction, the second side includes multiple protrusions arranged beneath the multiple cooling holes, and the second side includes a recessed wall recessed with respect to and adjoining the lateral walls (104,106) and the other of the forward and aft rails (100,102), the impingement plate (108;208) engaging the recessed wall. an airfoil extending radially from a first side of a platform, a pocket (90; 190) provided in the platform on a second side opposite the airfoil, forward and aft rails (100,102) extending from the second side of the platform, one of the forward and aft rails (100,102) including a radial surface (118;218); a cooling passage extending through the airfoil to the second side; and an impingement plate (108;208) secured to the platform over the pocket (90;190), the impingement plate (108;208) including a radial flange (120;220) engaging the radial surface (118;218), and an opening aligned with the cooling passage to provide fluid communication therebetween, wherein the pocket is circumscribed by a perimeter, the perimeter provided by the forward and aft rails (100,102) and spaced apart lateral walls (104,106) joining the forward and aft rails (100,102), wherein the second side includes a ridge circumscribing the cooling passage and engaging the impingement plate near the opening,wherein the impingement plate (108;208) is unsupported immediately beneath the radial flange (120;220) in the radial direction and includes a cooling wall that provides the opening, and the cooling wall includes multiple cooling holes facing the second side; characterised in that: the impingement plate is supported by at least one pedestal near the radial flange in the radial direction, the second side includes multiple protrusions arranged beneath the multiple cooling holes, and the second side includes a recessed wall recessed with respect to and adjoining the lateral walls (104,106) and the other of the forward and aft rails (100,102), the impingement plate (108;208) engaging the recessed wall. the impingement plate is supported by at least one pedestal near the radial flange in the radial direction, the second side includes multiple protrusions arranged beneath the multiple cooling holes, and the second side includes a recessed wall recessed with respect to and adjoining the lateral walls (104,106) and the other of the forward and aft rails (100,102), the impingement plate (108;208) engaging the recessed wall.