Blended Wing Body (or Hybrid Wing Body) aircraft display a flattened and airfoil shaped body due to the blending of the wing and body at the wing root reducing the traditional “step” fond between these. this “blend” produces most of the lift with the wings now contributing the balance. Naturally the implications of this design are many amongst which a lesser need for immense wing strength as payloads increase and thus aircraft capable of carrying more in terms of their structural strength.
Generally, the “internal” body form is composed of distinct and separate wing / body structures and in this case the wings are smoothly blended into the body by means of an external skin which also lends strength to the structure. If we should compare the definition of these configurations or rather designs then the blended or flying wing design could be defined as a tail-less fixed-wing aircraft with no defined fuselage or wing allowing most of the crew, payload and associated equipment to be housed inside the main wing structure.
In terms of the important lift to drag ratio that different designs offer differing solutions for, a blended wing body has a lift-to-drag ratio no less than 50% greater than a conventional airplane configuration. This blended configuration incorporates design features from what could be considered a futuristic fuselage as well as traditional flying wing design mostly seen in models or in unmanned aerial vehicles to date. The expected and mostly proven benefits of the of the Blended -wing body design are efficient high-lift wings and a wide airfoil-shaped body which means: the entire aircraft contributes to the generation of lift thereby potentially increasing fuel economy and range, while at the same time massive increase in internal payload are obtained.
One of the major obstacles will undoubtedly be cost as the design requires new building technologies and thus also new equipment unlike the current equipment around which factories have evolved during the growth of the traditional aircraft that most major companies build today.
Associated to the larger payload, the comfort of passengers in a wider cabin would be fantastic but owing to simple economics, it would perhaps not be naive to think that the airlines would simply pack more passengers in there thus not really bringing any added change to passenger experience other than 20 or 30 seats in a row versus 12. However, that said, the cost of carriage per passenger could be reduced as the reduction in general cruise drag e.g. interference drag (a part of parasite drag) would also contribute to lesser fuel spending, the biggest obstacle faced by all airlines in today’s world. Military bombers such as the B2 have already proven the capabilities of these designs.
Boeing is actively involved in researching this design for the purpose of civil travel: