Guy Norris/LOS ANGELES
McDonnell Douglas (MDC) and California's Stamford University plan to test a large-scale model of a futuristic blended-wing-body (BWB-1-1)airliner in 1997.
The powered model will have a wingspan of between 6.1m and 7.6m, according to MDC, which says that it is "-getting really serious about the proposal". NASA is also participating in, and partially funding, the research.
As configured, a full-scale BWB-1-1 airliner would be able to carry some 800 passengers over a design range of around 12,950km (7,000nm). Despite a maximum take-off weight of more than 370t, it would require only three 223kN (50,000lb)-thrust-class engines because of the 20%-higher lift/ drag coefficient of the lifting body and blended wing, compared with a conventional airliner.
MDC says, that the BWB-1-1's 88m wing span, could be reduced by "40ft [12.2m] or so", to make it more compatible with airport infrastructure designed to accommodate the Boeing 747-400.
Key advantages of the design include its improved operating economics and potential use of lightweight, advanced, structures. BWB-1-1 fuel consumption is projected to be around 27% lower than that of an equivalent, conventional, aircraft, while operating empty weight could be up to 12% lower.
Depending on the progress of initial tests and further research during the next few years, MDC is considering bringing forward the planned entry-into-service date from 2010 to 2005. One of the main aerodynamic and performance concerns is expected to focus on the BWB-1-1's aft-deck-mounted turbofans.
MDC believes that careful positioning of the intakes will avoid problems of boundary-layer disruption, but says that alternative pylon-mounted positions will also be evaluated.
Source: Flight International