The Cycloman PR Hurricanes and Meteorology Forums

by **TheCyclomanPR** on Tue Jul 24, 2007 2:56 am

Aunque parece tan real, la foto de arriba es un fotomontaje! Exelente trabajo quien quiera que lo haya hecho!

Boeing to take on Airbus with (1000 seat) giant 797 Blended Wing plane
Boeing is preparing a 1000 passenger jet that could reshape the Air travel industry for the next 100 years.

The radical Blended Wing design has been developed by Boeing in cooperation with the NASA Langley Research Centre. The mammoth plane will have a wing span of 265 feet compared to the 747's 211 feet, and is designed to fit within the newly created terminals used for the 555 seat Airbus A380, which is 262 feet wide. The new 797 is in direct response to the Airbus A380 which has racked up 159 orders, but has not yet flown any passengers. Boeing decide to kill its 747X stretched super jumbo in 2003 after little interest was shown by airline companies, but has continued to develop the ultimate Airbus crusher 797 for years at its Phantom Works research facility in Long Beach, Calif.

The Airbus A380 has been in the works since 1999 and has accumulated $13 billion in development costs, which gives Boeing a huge advantage now that Airbus has committed to the older style tubular aircraft for decades to come. There are several big advantages to the blended wing design, the most important being the lift to drag ratio which is expected to increase by an amazing 50%, with overall weight reduced by 25%, making it an estimated 33% more efficient than the A380, and making Airbus's $13 billion dollar investment look pretty shaky.

High body rigidity is another key factor in blended wing aircraft, It reduces turbulence and creates less stress on the air frame which adds to efficiency, giving the 797 a tremendous 8800 nautical mile range with its 1000 passengers flying comfortably at mach .88 or 654 mph (+-1046km/h) cruising speed another advantage over the Airbus tube-and-wing designed A380's 570 mph (912 km/h) The exact date for introduction is unclear, yet the battle lines are clearly drawn in the high-stakes war for civilian air supremacy

EL avión ya ha pasado varias pruebas en el wind tunel y sus desarrolladores han volado modelos a escala del mismo. Con este proyecto la compañía Boeing espera competir con el nuevo modelo Airbus A380 que ya fue introducido y que cuenta entre otras cosas con dos pisos y capacidad para mas de 500 pasajeros.

Blended wing’ craft passes wind-tunnel tests
11:10 14 November 2005
NewScientist.com news service
Kelly Young
A futuristic "blended wing" plane developed by NASA has passed crucial wind-tunnel tests. These reveal that engineers may have overcome some of the controllability challenges associated with the revolutionary aircraft design.

Designs for blended wing planes are a dramatic leap from that of today's passenger jets – instead having a tube-like fuselage. They look more like paper aeroplanes with engines mounted on top and at the rear.

The unusual shape is much more aerodynamic than a normal plane, which means it could use 20% less fuel. And it should also be much quieter for people on the ground because the engines sit on top of its wings instead of hanging below.

But the extremely sleek design means doing away with a tail – a crucial control element – so engineers have had to come up with other ways to make the aircraft pitch, yaw and roll. For a blended wing plane, this means relying on curved flaps along the edge of each wing and rudders on each wingtip.

Lift drop

NASA engineers have struggled to find the perfect configuration for the design but the latest tests suggest they are getting closer. They took a 5% scale model of their latest blended wing design to a wind tunnel at Langley Research Center in Hampton, Virginia, US, for a free-flying test.

"We were kind of concerned early on that it was going to be difficult to fly,” says Dan Vicroy, head of the project at NASA. "The bottom line from the test: this particular configuration flew great."

The engineers were particularly keen to see what would happen when the aircraft approached maximum lift and then lift suddenly dropped, as can happen when an aircraft hits turbulence. Unlike previous designs, the aircraft did not start to roll or pitch backwards.

During wind tunnel tests, a model is normally mounted while wind flows around it, allowing engineers to measure forces on the static design. This time, however, three "pilots" remotely controlled the scale model's movement during the test. It was the first time anyone has tried such a test of a blended wing design.

Renewed interest

The other design challenge presented by a blended wing body is structural. A tube-shaped fuselage is easy to keep pressurized because pressure is distributed evenly inside. When you squash the tube down into such an irregular shape, it places more stress on the structure. NASA researchers hope to combat this by using composite structures and by adding pillars inside to add strength.

NASA has been researching the flying wing design since the early 1990s and has tested concepts with McDonnell-Douglas, which was taken over by Boeing in 1998. Next summer, Boeing and Cranfield University in the UK will test another blended wing design, the X-48B, at Dryden Flight Research Center in California, US.

Aircraft companies, such as Boeing, have discussed using such an aircraft for both commercial and military purposes. If a company were to start building a blended wing body aircraft today, it could hit the market in about seven years.

"With today’s gas prices, it’s getting renewed interest," Vicroy told New Scientist.