Aircraft and associated method of conditioning cabin air

A method of conditioning cabin air of an aircraft having a cabin, a pressurized air line fluidly connecting the cabin, an electric engine powered by a battery, the electric engine drivingly coupled to a rotary airfoil device, and a heat pump, the method comprising:

• circulating a coolant in a coolant circuit;
• driving a flow of pressurized air in the pressurized air line;
• circulating a refrigerant in the heat pump;
• transferring heat from at least one of the electric engine and the battery to the coolant;
• transferring heat from the coolant to the refrigerant;
• transferring heat from the pressurized air to the refrigerant;
• and
• delivering the pressurized air to the cabin subsequently to said transferring heat from the pressurized air.

An aircraft comprising:

• a cabin adapted to receive one or more persons;
• a rotary airfoil device;
• an electric engine drivingly coupled to the rotary airfoil device;
• a battery powering the electric engine;
• a lubricant subsystem having a lubricant circuit and a lubricant pump operable to circulate a lubricant in the lubricant circuit;
• a heat pump having a refrigerant circuit fluidly connecting, in sequence, a compressor, a condenser, an expansion valve, a first evaporator, and an environmental control line branching off from the refrigerant circuit between the condenser and the first evaporator, the environmental control line having a second evaporator and reconnected to the refrigerant circuit between the first evaporator and the compressor, the first evaporator connected in heat exchange relationship with the lubricant circuit;
• and
• a pressurized air subsystem having a pressurized air line operable to deliver pressurized air from a pressurized air source to the cabin, the pressurized air line connected in heat exchange relationship with the second evaporator.