Hydraulic and pneumatic control circuit having a fuel/air heat exchanger for a turbojet

A hydraulic and pneumatic control circuit for a turbojet, the circuit comprising:

• a main hydraulic line having an oil/fuel heat exchanger with a function of transferring heat from the oil flowing in an oil circuit of the turbojet to the fuel flowing in the main hydraulic line;
• a first hydraulic line for feeding fuel to a combustion chamber of the turbojet;
• a second hydraulic line for feeding fuel to one or more hydraulic actuators serving to control variable geometry equipment of the turbojet, each hydraulic actuator being fed with fuel via an electrohydraulic servovalve;
• and
• a pneumatic line for feeding air to a pneumatic control member for bleed valves of a compressor of the turbojet and a blade tip clearance control valve of a turbine of the turbojet;
• the circuit further comprising a fuel/air heat exchanger positioned on the second hydraulic line upstream from the hydraulic servovalve and on the pneumatic line upstream from the pneumatic control member in order to transfer heat from the air flowing in the pneumatic line to the fuel flowing in the second hydraulic line, wherein the oil/fuel heat exchanger does not have a function of transferring heat between the oil flowing in an oil circuit of the turbojet and the fuel flowing in the second hydraulic line.