Control apparatus for a gas-turbine aeroengine

An apparatus for controlling a gas-turbine aeroengine mounted on an aircraft and having at least a high-pressure turbine rotated by injection of high-pressure gas produced upon ignition and combustion of an air-fuel mixture in a combustion chamber, and a low-pressure turbine located downstream of the high-pressure turbine to be rotated by low-pressure gas exiting the high-pressure turbine, comprising:

• a low-pressure turbine rotational speed sensor adapted to detect a rotational speed of the low-pressure turbine (N1);
• a high-pressure turbine rotational speed sensor adapted to detect a rotational speed of the high-pressure turbine (N2);
• a low-pressure turbine rotational speed sensor normality discriminator that compares an estimated operating parameter of the rotational speed of the low-pressure turbine with a detected value of the rotational speed of the low-pressure turbine to generate a comparison result and discriminates whether or not the low-pressure turbine rotational speed sensor is operating abnormally by determining if the detected value of the rotational speed of the low-pressure turbine exceeds the estimated operating parameter of the rotational speed of the low-pressure turbine;
• and
• a controller that establishes a first value as an upper limit value of the rotational speed of the high-pressure turbine (N2) and controls the rotational speed of the high-pressure turbine based on the established upper limit value;
• wherein the controller has an upper limit value changer that changes the upper limit value to a second value that is lower than the first value, when the low-pressure turbine rotational speed sensor normality discriminator discriminates that the low-pressure turbine rotational speed sensor is operating abnormally based on the comparison result, and the controller controls rotational speed of the high-pressure turbine based on the second value.