Patent US 5,197,280

A control system for a gas turbine engine receives a signal representative of a first target engine operating condition and also receives a signal representative of an actual engine condition. The system produces an error signal representative of the difference between the target signal and the actual engine condition signal. A gain means adjusts the gain of the error signal to be equal to the desired change in the controlled engine parameter. The output of the gain means is then coupled to an activator of the engine which controls the parameter.