Patent attributes
Thermo-pneumatic anti-icing systems include port and starboard anti-icing subsystems operatively interconnecting heated engine bleed air discharged from port side and starboard side turboprop engines with port and starboard airfoils, respectively, associated with an aircraft to thereby provide in-flight anti-icing protection to the port and starboard airfoils, and an auxiliary power unit (APU) capable of discharging a supply of heated APU bleed air to the port and starboard anti-icing subsystems during an abnormal single engine or a single pneumatic bleed air operational condition. A controller may command respective port and starboard cross bleed valves to open and thereby allow the APU bleed air to be supplied to the one port or starboard anti-icing subsystem that is incapable of delivering heated engine bleed air from the port side turboprop engine or the starboard side turboprop engine, respectively. The port and starboard airfoils are thus each protected against inflight icing during the abnormal single engine or single pneumatic bleed air operational condition.