Heating Control System and Method for Unpressurized Aircraft

A method for heating an unpressurized aircraft, comprising:

• receiving, via a controller, a desired air temperature from a control panel;
• calculating, via the controller, a target duct air temperature based on the desired air temperature;
• determining, via the controller, an actual duct air temperature via a duct air temperature sensor disposed in an air duct;
• calculating a target modulation of one or more ram air valves based on a difference between the target duct air temperature and the actual duct air temperature;
• modulating one or more of the ram air valves via the controller based on the target modulation;
• introducing a bleed air from a turbine engine to a heat exchanger;
• introducing a temperature control air from one of the one or more ram air valves to the heat exchanger for cooling the bleed air to provide a temperature-controlled air;
• mixing the temperature-controlled air from the heat exchanger with an ejector ram air in an ejector;
• and
• providing air from the ejector to an occupied compartment of the unpressurized aircraft via the air duct.

A method for heating an unpressurized aircraft, comprising:

• providing a desired air temperature to a controller via a control panel;
• calculating, via the controller, a target duct air temperature based on the desired air temperature;
• determining, via the controller, an actual duct air temperature via a duct air temperature sensor;
• determining a temperature error based on a difference between the actual duct air temperature and the target duct air temperature;
• calculating a target ejector ram air valve position based on the temperature error;
• determining a measured ejector ram air valve position from a position sensor;
• determining a valve error based on the difference between the target ejector ram air valve position and the measured ejector ram air valve position;
• maintaining a position of an ejector ram air valve when the valve error is less than a predetermined value;
• and
• adjusting the position of the ejector ram air valve based on the valve error when the valve error is greater than the predetermined value.