Aircraft fluid ice protection system

A method for assembling a fluid ice protection system onboard an aircraft, the method comprising:

• affixing a plenum back wall to an interior surface of an inlet cowl of a nacelle of the aircraft to define a plenum between the interior surface and a front surface of the plenum back wall, the nacelle surrounding a rotor assembly of an aircraft propulsion system, the plenum back wall aligns with a plurality of perforations defined through a thickness of the inlet cowl such that the plenum is fluidly connected to the perforations, wherein the inlet cowl includes first and second protrusions that project from the interior surface and have respective ramp surfaces, wherein affixing the plenum back wall to the inlet cowl comprises bonding, via a first lap joint, a first flange of the plenum back wall to the ramp surface of the first protrusion and bonding, via a second lap joint, a second flange of the plenum back wall to the ramp surface of the second protrusion, wherein the plenum is defined between the first and second protrusions;
• coupling a fluid delivery network to the plenum back wall, the fluid delivery network configured to supply an anti-ice liquid into the plenum for the anti-ice liquid in the plenum to penetrate through the perforations onto an exterior surface of the inlet cowl along a leading edge section of the inlet cowl;
• receiving, at a controller that includes one or more processors, sensor data generated by one or more temperature sensors that indicates a temperature of the anti-ice liquid within the fluid delivery network;
• determining, via the controller and based on the sensor data, that the temperature of the anti-ice liquid within the fluid delivery network is below a designated threshold temperature value;
• and
• activating a heater device from an inactive state to warm the anti-ice liquid in response to determining that the temperature of the anti-ice liquid is below the designated threshold temperature value.

An aircraft comprising:

• an electrical energy storage device;
• one or more propulsion systems each comprising a motor, a rotor assembly, and a nacelle that surrounds the motor and the rotor assembly, wherein the motor is electrically connected to the electrical energy storage device and powered by the electrical energy storage device to drive the rotor assembly to generate thrust for flight of the aircraft;
• and
• a fluid ice protection system incorporated into the nacelle of the one or more propulsion systems, the fluid ice protection system comprising:
• a plenum back wall affixed to an interior surface of an inlet cowl of the nacelle to define a plenum between the interior surface and a front surface of the plenum back wall, the inlet cowl defining a plurality of perforations through a thickness of the inlet cowl, the perforations fluidly connected to the plenum, wherein the inlet cowl includes first and second protrusions that project from the interior surface and have respective ramp surfaces, wherein the plenum back wall includes a first flange that is bonded, via a first lap joint, to the ramp surface of the first protrusion and a second flange that is bonded, via a second lap joint, to the ramp surface of the second protrusion to affix the plenum back wall to the inlet cowl, wherein the plenum is defined between the first and second protrusions;
• a fluid delivery network coupled to the plenum back wall and configured to supply an anti-ice liquid into the plenum for the anti-ice liquid in the plenum to penetrate through the perforations onto an exterior surface of the inlet cowl along a leading edge section of the inlet cowl;
• a heater device;
• one or more temperature sensors configured to generate sensor data indicative of a temperature of the anti-ice liquid within the fluid ice protection system;
• and
• a controller that includes one or more processors, the controller operably connected to the heater device and configured to activate the heater device from an inactive state to warm the anti-ice liquid in response to the sensor data indicating that the temperature of the anti-ice liquid is below a designated threshold temperature value.