Design Aspects of Systems in All-Electric Aircraft

The paper deals with the emerging and topical subject of All-Electric Aircraft in which the electric system in an advanced airplane serves all the functions and services normally supplied by multiple power systems, such as engine bleed air, hydraulics, pneumatics, and conventional type electric power systems. Engine starting is of particular interest because of its demands for special logistic and maintenance ground support. Military and commercial aircraft typically use pneumatic, cartridge, fuel/air (combustion) or monopropellant starting methods, so these must be replaced by electric starting. The trend of the advanced technology engines is towards high bypass and high compression ratios, making them increasingly sensitive to tapping the compressor airflow: The energy-efficient engine is, therefore, an important design consideration in the All-Electric Airplane. The replacement of systems, such as hydraulics, used for hydromechanical actuation and powering of flight controls; the bleed air system, used for thrust reversing/air turbine motors and engine/wing icing protection; the environmental control system, used for cabin/cockpit air conditioning, electric/avionic cooling; and the electric system for powering the electric/avionics systems are all key to the maturation of the All-Electric Airplane.