NASA Langley Research Center has developed a novel aircraft design that can carry 150+ passengers over a range of 3,500 nautical miles. Key features include a turboelectric propulsion system, twin underwing turbofans, and a rear-fuselage, electrically driven, boundary layer ingesting fan. The design is developed for single-aisle-class aircraft (the largest commercial transport class in the world) to significantly reduce fuel burn compared to current aircraft.
The novel propulsion architecture uses hydrocarbon fuels to power two underwing turbofans that also contain generators. The underwing turbofans burn traditional jet fuel and provide thrust throughout the mission. The generators on the turbofans extract power from the fan shaft and send the power to a rear fuselage electric motor operating at a constant 3,500 hp. The motor then turns an annular fan that operates at a fan pressure ratio of 1.25. The rear fuselage propulsor is extremely efficient, allowing the turbofans to be decreased in size. This can reduce weight penalties associated with the additional electrical components and rear fan.