Stall detection and recovery system for a gas turbine engine

A stall detection and recovery system (10) for a gas turbine engine (1) comprises surge detection means (50 for detecting an engine surge and providing a surge detection signal (154) for indicating said engine surge. The system also includes stall detection means to provide a stall detection signal (48) relating to a condition of gas flowing through the engine (1). The system (10) also includes stall recovery means (58) to receive the surge detection signal (154) and the stall detection signal. The stall recovery means (58) is arranged to control combustor operating means, whereby when the stall detection signal (48) indicates an engine stall, the stall recovery means controls the combustor operating means to effect recover from the stall.