A supersonic jet aircraft and a method of operating the same. The supersonic jet aircraft having at least three turbofan engines and an engine management computer. A first engine of the at least three turbofan engines is configured to be de-activatable during flight to move from an operational state in which it provides thrust to an operational state in which it stops providing thrust. Other engines of the at least three turbofan engines are configured to provide sufficient thrust to the supersonic jet aircraft when the first engine is de-activated such that the aircraft can perform a supersonic climb operation and/or a supersonic cruise operation.