Abstract: An aircraft comprising a main engine to provide a supply of bleed air, an APU housing within an APU compartment and having an APU bleed valve, an APU bleed air duct connecting main engine with the APU, and a bleed air heating system for the APU compartment comprising an auxiliary pipeline connecting the APU bleed air duct with the APU compartment, a temperature sensor, an auxiliary pipeline valve to control the discharge of bleed air into the APU compartment, and a temperature controller configured to establish a heating operation mode, when the sensed temperature falls below a minimum temperature threshold value, and a standby operation mode, when the sensed temperature surpasses a maximum temperature threshold value. The temperature controller operates the main engine and the valves to establish these operation modes.

Abstract: An aircraft comprising a main engine to provide a supply of bleed air, an APU housing within an APU compartment and having an APU bleed valve, an APU bleed air duct connecting main engine with the APU, and a bleed air heating system for the APU compartment comprising an auxiliary pipeline connecting the APU bleed air duct with the APU compartment, a temperature sensor, an auxiliary pipeline valve to control the discharge of bleed air into the APU compartment, and a temperature controller configured to establish a heating operation mode, when the sensed temperature falls below a minimum temperature threshold value, and a standby operation mode, when the sensed temperature surpasses a maximum temperature threshold value. The temperature controller operates the main engine and the valves to establish these operation modes.