GAS TURBINE ENGINE AND OPERATION METHOD

A gas turbine (10) engine and method of operation. The gas turbine engine (10) comprises a heating device configured to heat a rotor disc (32, 72) of the engine (10). A method of operation the heating device comprises detecting an engine acceleration or deceleration event, or determining that an engine acceleration or deceleration event is imminent or may be imminent. On detection of an engine acceleration or deceleration event, or in advance of the engine acceleration or deceleration event, increasing turbine rotor disc heat input to raise a temperature of the turbine rotor disc or reduce a cooling rate of the rotor disc.