A method of controlling a gas turbine engine, the gas turbine engine having in axial flow series a compressor, a combustor, a compressor-turbine and an exhaust, the compressor comprises variable guide vanes, the gas turbine capable of operating in at least - a high output power range, - a medium-high output power range, - a medium output power range, - a medium-low output power range (70R, 70R') and - a low output power range, the method comprising the steps - during the medium-high output power range varying the angle of the variable guide vanes so that a third predetermined temperature of the combustor is maintained, - during the medium output power range the variable guide vanes are at their most closed position and bleeding a gas from a downstream part of the compressor to an upstream part of the compressor so that a first predetermined temperature of the combustor is maintained, - during the medium-low output power range (70R, 70R') the variable guide vanes are at their most closed position and bleeding a gas from a downstream part of the compressor to an upstream part of the compressor is a maximum and bleeding a gas from the downstream part of the compressor to the exhaust so that a second predetermined temperature of the combustor is maintained. the gas turbine engine having in axial flow series a compressor, a combustor, a compressor-turbine and an exhaust, the compressor comprises variable guide vanes, the gas turbine capable of operating in at least - a high output power range, - a medium-high output power range, - a medium output power range, - a medium-low output power range (70R, 70R') and - a low output power range, - a high output power range, - a medium-high output power range, - a medium output power range, - a medium-low output power range (70R, 70R') and - a low output power range, the method comprising the steps - during the medium-high output power range varying the angle of the variable guide vanes so that a third predetermined temperature of the combustor is maintained, - during the medium output power range the variable guide vanes are at their most closed position and bleeding a gas from a downstream part of the compressor to an upstream part of the compressor so that a first predetermined temperature of the combustor is maintained, - during the medium-low output power range (70R, 70R') the variable guide vanes are at their most closed position and bleeding a gas from a downstream part of the compressor to an upstream part of the compressor is a maximum and bleeding a gas from the downstream part of the compressor to the exhaust so that a second predetermined temperature of the combustor is maintained. - during the medium-high output power range varying the angle of the variable guide vanes so that a third predetermined temperature of the combustor is maintained, - during the medium output power range the variable guide vanes are at their most closed position and bleeding a gas from a downstream part of the compressor to an upstream part of the compressor so that a first predetermined temperature of the combustor is maintained, - during the medium-low output power range (70R, 70R') the variable guide vanes are at their most closed position and bleeding a gas from a downstream part of the compressor to an upstream part of the compressor is a maximum and bleeding a gas from the downstream part of the compressor to the exhaust so that a second predetermined temperature of the combustor is maintained.