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This paper describes how the MEE (More Electric Engine) system contributes toward an integrated propulsion control system, with a particular focus on commercial aircraft. Current aircraft systems control the engine rotational speed or pressure ratio to control propulsion, but in future aircraft systems, control of the engine thrust itself will be required. Because controlling engine thrust can be used as an effective method of changing the aircraft speed and/or attitude, various approaches to engine thrust control have been investigated and developed. In this investigation, key technical issues have emerged; one is which is the need for an enhanced engine thrust response for stable control of the aircraft. The other is accurate estimation of engine thrust in flight. Incremental data processing capability is also required due to the need for additional monitoring, evaluation and calculation of engine parameters to ensure safe engine operation.

To improve an energy optimization issue of ECS for MEA, we propose our concept in which ACS is replaced with VCS. A VCS is generally evaluated as auxiliary or limited cooling system of an aircraft. Cooling demand of commercial aircraft usually becomes large due to ventilation air at hot day conditions. In case of using conventional VCS for whole cooling demand, the ECS becomes too heavy as aircraft equipment. Though ACS's light weight is advantageous, the issue that VCS will be available for aircraft ECS is important for saving energy. ECS of commercial aircraft should work for three basic functions, i.e. pressurization, ventilation, and temperature control. The three functions of the ECS for bleed-less type of MEA can be distributed among equipment of the ECS. MDFAC works for pressurization and ventilation. Therefore, we should select appropriate system for only temperature control.

This paper describes the comparison of electromagnetic characteristics of two different superconducting-motor structures for electrified aircraft propulsion systems. Future electrified aircraft demand higher output (over 16 kW/kg) and higher efficiency (> 98%) for their motors in comparison with current ones. To satisfy the demands, two kinds of superconducting motors are dealt in this study: one is partially superconducting motors (PSCMs), made of superconducting field coils and copper armature windings; the other is the fully superconducting motors (FSCMs) made of superconducting field/armature windings. They are cooled at 20 K with liquid hydrogen. We designed these two motors with finite element method to obtain the output density of 16-20 kW/kg for future electrified propulsion systems. We selected 3.0- and 5.0 MW superconducting motors, considering the application to aircraft for almost 180 passengers and 44 MW rated power for take-off.