A control system for an aircraft turbine engine, the turbine engine comprising: ▪ a combustion chamber, ▪ a fuel metering valve including a metering slide, a position of which determines a volumetric flow rate of fuel injected into the combustion chamber and an actuator arranged to displace the metering slide depending on a control electric current (I_com), ▪ a position sensor arranged to measure a position of the metering slide and deliver a position measurement (M_Pos), ▪ a speed sensor arranged to measure a rotational speed of the turbine engine and deliver a rotational speed measurement (M_XNBP), and ▪ a monitoring unit arranged to deliver a rotational speed setpoint (C_XNBP), to detect a failure of the position sensor and to deliver a failure signal (Sd) in the case of detection of a failure of the position sensor, the control system comprising: ▪ a nominal-mode processing chain including: - a global corrector arranged to receive the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP) and determine a fuel mass flow rate setpoint (C_WF) depending on the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP), - a converter arranged to convert the fuel mass flow rate setpoint (C_WF) into a position setpoint (C_Pos), and - a local corrector arranged to receive the position setpoint (C_Pos) and the position measurement (M_Pos) and determine a nominal-mode control electric current (I_nom) depending on the position setpoint (C_Pos) and the position measurement (M_Pos), ▪ a degraded-mode processing chain including a direct corrector arranged to receive the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP) and determine a degraded-mode control electric current (I_deg) depending on the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP), and ▪ a mode management module arranged to receive the failure signal (Sd), the nominal-mode control electric current (I_nom) and the degraded-mode control electric current (I_deg), and to deliver, to the actuator of the fuel metering valve, the nominal-mode control electric current (I_nom) in the absence of reception of the failure signal and the degraded-mode control electric current (I_deg) in the case of reception of the failure signal. ▪ a combustion chamber, ▪ a fuel metering valve including a metering slide, a position of which determines a volumetric flow rate of fuel injected into the combustion chamber and an actuator arranged to displace the metering slide depending on a control electric current (I_com), ▪ a position sensor arranged to measure a position of the metering slide and deliver a position measurement (M_Pos), ▪ a speed sensor arranged to measure a rotational speed of the turbine engine and deliver a rotational speed measurement (M_XNBP), and ▪ a monitoring unit arranged to deliver a rotational speed setpoint (C_XNBP), to detect a failure of the position sensor and to deliver a failure signal (Sd) in the case of detection of a failure of the position sensor, ▪ a nominal-mode processing chain including: - a global corrector arranged to receive the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP) and determine a fuel mass flow rate setpoint (C_WF) depending on the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP), - a converter arranged to convert the fuel mass flow rate setpoint (C_WF) into a position setpoint (C_Pos), and - a local corrector arranged to receive the position setpoint (C_Pos) and the position measurement (M_Pos) and determine a nominal-mode control electric current (I_nom) depending on the position setpoint (C_Pos) and the position measurement (M_Pos), - a global corrector arranged to receive the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP) and determine a fuel mass flow rate setpoint (C_WF) depending on the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP), - a converter arranged to convert the fuel mass flow rate setpoint (C_WF) into a position setpoint (C_Pos), and - a local corrector arranged to receive the position setpoint (C_Pos) and the position measurement (M_Pos) and determine a nominal-mode control electric current (I_nom) depending on the position setpoint (C_Pos) and the position measurement (M_Pos), ▪ a degraded-mode processing chain including a direct corrector arranged to receive the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP) and determine a degraded-mode control electric current (I_deg) depending on the rotational speed setpoint (C_XNBP) and the rotational speed measurement (M_XNBP), and ▪ a mode management module arranged to receive the failure signal (Sd), the nominal-mode control electric current (I_nom) and the degraded-mode control electric current (I_deg), and to deliver, to the actuator of the fuel metering valve, the nominal-mode control electric current (I_nom) in the absence of reception of the failure signal and the degraded-mode control electric current (I_deg) in the case of reception of the failure signal.