More electric power system concepts for an environmentally responsible aircraft (N+2)

NASA has set goals for aircraft entering service in the N+2 timeframe (between 2020 and 2025) of 50 % reduced fuel burn, 75% less NOX emissions and up to 42 dB of noise reduction with respect to the 1998 Environmental Impact Statement (EIS) Conventional Reference Vehicle. In order for these goals to be achieved a number of fundamental changes must be made to the design of the aircraft, both in terms of the airframe and the subsystems within the aircraft, through the utilisation of onboard electric power based subsystems. This paper looks to assess how the current MEA design concepts are enabling the N+1 goals to be met as well as looking to the future and how more advanced concepts will enable the N+2 goals to be achieved. The paper identifies areas where improvement is required to ensure that safety standards are met and that efficiency goals can be met and surpassed. The paper concludes by highlighting the technological and electrical systems integration challenges which must be overcome to accomplish the N+2 goals using the more/all electric aircraft design philosophy.