/. - "Borne out of the same NASA research program that gave birth to MIT's D 'double bubble,' Boeing's Subsonic Ultra Green Aircraft Research (SUGAR) Volt concept is a twin-engine aircraft design notable for its trussed, elongated wings and electric battery gas turbine hybrid propulsion system — a system designed to reduce fuel burn by more than 70 percent and total energy use by 55 percent. The goal of the NASA supersonic research program is to find aircraft designs that will significantly reduce noise, nitrogen oxide emissions, fuel burn and air traffic congestion by the year 2035."