Lockheed Martin's advanced vehicle concept proposes a box wing design, which is now feasible thanks to modern lightweight composite (nonmetallic) materials, landing gear technologies and other advancements. Its Rolls Royce Liberty Works Ultra Fan Engine achieves a bypass ratio (flow of air around engine compared to through the engine) nearly five times greater than current engines, pushing the limits of turbofan technology to maximize efficiency.
This design is among those presented to NASA at the end of 2011 by companies that conducted NASA-funded studies into aircraft that could enter service in 2025.
NASA/Lockheed Martin
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