There is provided a system for controlling at least first and second engines of an aircraft, comprising a common controlling unit configured to convert data representative of a thrust command transmitted by an actuating element controllable by a pilot or by an auto- throttle of the aircraft, into: (a) at least one first command usable by a controller of the first engine for controlling its operation based at least on said first command, and (b) at least one second command usable by a controller of the second engine for controlling its operation based at least on said second command, wherein said common controlling unit is operable to perform said conversion based at least on data representative of a level of operability of each engine, thereby making each engine to either comply with said thrust command or to operate differently from said thrust command, based at least on its level of operability.