The Burnelli Web Site
spacer
NASA / McDonnell Douglas Blended-Wing-Body
from McDonnell Douglas "Presentation Packet" (1996)

The BWB is an advanced long-range ultra-high-capacity airliner which is being studied by McDonnell Douglas and NASA. Slated for service entry between 2010 and 2020, the BWB carries 800 passengers (mixed class) over a range of 7,000 nautical miles at a cruise Mach number of 0.85. The principal feature of the BWB is the wide double-deck body which is blended into the wing This reduces surface area and provides improved spanloading. The resulting configuration resembles the Northrop B-2, and offers dramatic improvements in aerodynamic and structural efficiency. Projections indicate a fuel-burn saving of 28% relative to a conventional double-deck transport of equivalent technology.

Normally, stable all-wing configurations arc difficult to trim without resorting to a download at the wingtip which increases drag. The BWB relies on advanced flight control computers to provide stability allowing the center-of-gravity to move aft where there is no longer a trim problem. Further performance improvements are realized through use of Boundary-Layer-Ingestion (BLI) in the engines. The aft engine installation allows the engines to scavenge a sizable portion of the airplane's boundary layer air, reducing the inlet ram drag and increasing efficiency.

The clean aerodynamics of the BWB require a novel structural concept for the pressurized cabin. A deep honeycomb sandwich with stitched resin-film-infusion face-sheets has been chosen as the baseline. The deep sandwich (5.5 inches) offers the bending rigidity required to withstand the pressure loading across the 150 inch wide cabin bays.

The high bypass ratio (BPR c 22) engines on the BWB can't provide bleed air for cabin pressurization or anti-icing. For this reason, all loads (electrical, hydraulic, and pneumatic) are serviced by an integrated electrical power system providing a substantial downsizing of power systems through load-sharing.

McDonnell Douglas and NASA are presently engaged in a 3 year BWB technology development study. They are teamed with - Stanford University who will fly a 17ft span Flight Control Testbed to explore stability and control of this novel configuration, the University of Southern California who are conducting inlet wind-tunnel tests, and, the University of Florida and Clark Atlanta University who are both designing cabin structure. NASA will also conduct a powered "wind-tunnel test" and a structures test. In addition, McDonnell Douglas is conducting Internal studies to determine the best payload/range combination for the BWB further develop the interior arrangement, evaluate military applications, and plan future sub-scale flight tests.

If you're interested in more information on the BWB please feel free to contact us.

Robert H. Liebeck
BWB Program Manager
Advanced Systems and Technology
McDonnell Douglas Aerospace
Mail Code 71-24
2401 E. Wardlow Rd. Long Beach Ca. 90807-5309
Phone: (310) 593-6138
Fax:(310) 593-9107

Mark A. Page
BWB Technical Program Manager
Advanced Systems and Technology
McDonnell Douglas Aerospace
Mail Code 71-35
2401 E. Wardlow Rd.
Long Beach Car 90807-5309
Phone: (310) 982-2844
Fax: (310) 593-7593

Blended-Wing-Body BWB
Range7,000 nmi800 Passengers in mixed class seating
TOGW823,000 lbsDouble-deck cabin
WingArea7,840 sq-ftStitched RFI Structure
Wingspan 280 FtSimple high-lift system

    BWB Performance relative to
    a Conventional Configuration:

    TOGW-15.2%OEW-12.3%
    L/D+20.6%Thrust-27%
    Fuel Burn-27.5%DOC-13%

Return to Sept. 20, 1995 letter