A gas turbine engine having a main rotational axis and comprising: a nacelle comprising a rear cowl defining a variable area exhaust nozzle; a blocker plate located adjacent and radially inwards of the rear cowl; an exhaust aperture; and, a motive system operable to move the rear cowl between a stowed configuration and a deployed configuration, the rear cowl comprising exactly two panels, and the motive system being operable to selectively rotate the panels about an axis having its largest 3-dimensional Euclidian space vector component parallel to the main rotational axis of the engine, wherein: in the stowed configuration, the two panels are in a closed position where the variable exit exhaust nozzle has a first total circumference, wherein the blocker plate is concealed radially within the rear cowl and does not contribute to the first total circumference; and, in the deployed configuration, the two panels are rotated by the motive system to an open position where the variable exit exhaust nozzle has a second total circumference, the two panels forming a circumferential aperture in the rear cowl, wherein the blocker plate is arranged so as to substantially block the circumferential aperture; and, wherein the first total circumference is smaller than the second total circumference, thereby altering the area of the exhaust aperture to provide a variable area nozzle. a nacelle comprising a rear cowl defining a variable area exhaust nozzle; a blocker plate located adjacent and radially inwards of the rear cowl; an exhaust aperture; and, a motive system operable to move the rear cowl between a stowed configuration and a deployed configuration, the rear cowl comprising exactly two panels, and the motive system being operable to selectively rotate the panels about an axis having its largest 3-dimensional Euclidian space vector component parallel to the main rotational axis of the engine, wherein: in the stowed configuration, the two panels are in a closed position where the variable exit exhaust nozzle has a first total circumference, wherein the blocker plate is concealed radially within the rear cowl and does not contribute to the first total circumference; and, in the deployed configuration, the two panels are rotated by the motive system to an open position where the variable exit exhaust nozzle has a second total circumference, the two panels forming a circumferential aperture in the rear cowl, wherein the blocker plate is arranged so as to substantially block the circumferential aperture; and, wherein the first total circumference is smaller than the second total circumference, thereby altering the area of the exhaust aperture to provide a variable area nozzle. in the stowed configuration, the two panels are in a closed position where the variable exit exhaust nozzle has a first total circumference, wherein the blocker plate is concealed radially within the rear cowl and does not contribute to the first total circumference; and, in the deployed configuration, the two panels are rotated by the motive system to an open position where the variable exit exhaust nozzle has a second total circumference, the two panels forming a circumferential aperture in the rear cowl, wherein the blocker plate is arranged so as to substantially block the circumferential aperture; and, wherein the first total circumference is smaller than the second total circumference, thereby altering the area of the exhaust aperture to provide a variable area nozzle.