Significant payload advantages in strategic airlift, air freight,[9] and aerial refueling roles Increased fuel efficiency – 10.9% better than a conventional widebody,[2] to over 20% than a comparable conventional aircraft.[10] Lower noise – NASA audio simulations show a 15dB reduction of Boeing 777-class aircraft,[11] while other studies show 22–42 dB reduction below Stage 4 level, depending on configuration.[1]