April 1995 issue
"MEGAPLANES - The New 800-Passenger Jetliners"
"Calculations show that an 800-passenger, double-decker BWB with
a 7,000-mile flying range would be 13 percent lighter and consume 31 percent
less fuel than a conventionally shaped megaplane cruising at the same 560-mph
speed. On a 6,500-mile flight from Los Angeles to Sydney, Australia, for
example, the savings would add up to 12,000 gallons of jet fuel."
"The BWB idea is a hybrid combining elements of a pure flying wing
like the Northrop B-2 stealth bomber, and traditional slender-winged airplanes.
It inherits valuable traits from both parents. "The way to evaluate
an airplane is to look at its weight, its surface area, and its wingspan,"
says BWB configuration designer Blaine Rawdon. "You want low weight
for obvious reasons. Small surface area-or wetted area-means less air-friction
drag, and wide wingspan gives you low vortex drag, the losses that occur
due to vortices forming at the wingtips. Everything came out nicer as we
converged on this shape." p. 56
"Deep-bellied and airfoil-shaped, the big bird's centerbody is
a spanloader" design that generates part of the airplane's lift while
providing a large interior volume for passengers, fuel and cargo. Stresses
are reduced by distributing aerodynamic lift and the weight of the payload
over this large area, which can be built from lighter, less expensive structures.
'When all the dust settles, you buy airplanes pretty much by the pound,'
says Robert Liebeck, leader of the BWB team...." p.56
"Traditional wide-span airplanes benefit from the same effect,
achieving a lift-to-drag ratio of about 18. The BWB's score on this important
aerodynamic-efficiency yardstick is predicted to be at least 25-a breakthrough
in airliner performance." p. 57
"Locating the duct on the back of the centerbody and burying the
engines inside its trailing edge will make the BWB an unusually quiet airplane,
while eliminating the risk of runway debris being inhaled by the engines.
Finally, the inlet is expected reduce fuel consumption about six percent
by swallowing the turbulent boundary layer of slower-moving air atop the
Letter to Editor-in-Chief from THE BURNELLI COMPANY, INC.