Method for automatically controlling the operating mode of a turboshaft engine of a helicopter that is not in a critical flight situation and comprises at least two turboshaft engines, the method comprising: - a step of receiving data (27, 28, 29) that are representative of the flight of the helicopter, - a step of determining an operating mode of said turboshaft engine, known as the selected mode, selected from a plurality of predetermined operating modes on the basis of said data that are representative of the flight of the helicopter, - a step of ordering the operating mode of said turboshaft engine into said selected mode, - a step of allocating, to each item of data received, an operating mode, known as the designated mode, that is selected from said plurality of operating modes and depends on the value of said item of data, wherein said step of determining a selected mode consists in selecting said selected mode from all of said designated modes provided by said allocation step, according to a predetermined order of priority, said turboshaft engine comprising a combustion chamber and an engine shaft, said method being characterised in that said plurality of predetermined operating modes comprises at least the following modes: - a standby mode known as normal idling, in which said combustion chamber is ignited and said shaft of the gas generator rotates at a speed of between 60 and 80 % of the nominal speed, - a standby mode known as normal super-idling, in which said combustion chamber is ignited and said shaft of the gas generator rotates at a speed of between 20 and 60 % of the nominal speed, - a standby mode known as assisted super-idling, in which said combustion chamber is ignited and said shaft of the gas generator rotates, in a mechanically assisted manner, at a speed of between 20 and 60 % of the nominal speed, - a standby mode known as banking, in which said combustion chamber is extinguished and said shaft of the gas generator rotates, in a mechanically assisted manner, at a speed of between 5 and 20 % of the nominal speed, - a standby mode known as stopping, in which said combustion chamber is extinguished and said shaft of the gas generator is completely stopped, - an urgent standby-leaving mode, in which the combustion chamber is ignited and the shaft of the gas generator is brought to a speed of between 80 and 105 % within a period of less than 10 seconds following an order to leave standby mode, - a normal standby-leaving mode, in which the combustion chamber is ignited and the shaft of the gas generator is brought to a speed of between 80 and 105 % within a period of between 10 seconds and 1 minute following an order to leave standby mode, - a nominal operating mode, in which the combustion chamber is ignited and the shaft of the gas generator is driven at a speed of between 80 and 105 %, and in that said predetermined order of priority is as follows: - nominal operating mode, - urgent standby-leaving mode, - normal standby-leaving mode, - normal idling mode, - normal super-idling mode, - assisted super-idling mode, - banking mode, - stopping mode. - a step of receiving data (27, 28, 29) that are representative of the flight of the helicopter, - a step of determining an operating mode of said turboshaft engine, known as the selected mode, selected from a plurality of predetermined operating modes on the basis of said data that are representative of the flight of the helicopter, - a step of ordering the operating mode of said turboshaft engine into said selected mode, - a step of allocating, to each item of data received, an operating mode, known as the designated mode, that is selected from said plurality of operating modes and depends on the value of said item of data, - a standby mode known as normal idling, in which said combustion chamber is ignited and said shaft of the gas generator rotates at a speed of between 60 and 80 % of the nominal speed, - a standby mode known as normal super-idling, in which said combustion chamber is ignited and said shaft of the gas generator rotates at a speed of between 20 and 60 % of the nominal speed, - a standby mode known as assisted super-idling, in which said combustion chamber is ignited and said shaft of the gas generator rotates, in a mechanically assisted manner, at a speed of between 20 and 60 % of the nominal speed, - a standby mode known as banking, in which said combustion chamber is extinguished and said shaft of the gas generator rotates, in a mechanically assisted manner, at a speed of between 5 and 20 % of the nominal speed, - a standby mode known as stopping, in which said combustion chamber is extinguished and said shaft of the gas generator is completely stopped, - an urgent standby-leaving mode, in which the combustion chamber is ignited and the shaft of the gas generator is brought to a speed of between 80 and 105 % within a period of less than 10 seconds following an order to leave standby mode, - a normal standby-leaving mode, in which the combustion chamber is ignited and the shaft of the gas generator is brought to a speed of between 80 and 105 % within a period of between 10 seconds and 1 minute following an order to leave standby mode, - a nominal operating mode, in which the combustion chamber is ignited and the shaft of the gas generator is driven at a speed of between 80 and 105 %, - nominal operating mode, - urgent standby-leaving mode, - normal standby-leaving mode, - normal idling mode, - normal super-idling mode, - assisted super-idling mode, - banking mode, - stopping mode.