- A reduction in noise of 70 decibels
- A reduction of 75% on the CAEP / 6 standard for NO emissions
- A reduction of 70% gasoline consumption
- The aircraft must be able to operate within a Metroplex
The wing box configuration is based on Prandtl ?? s principle of 'best wing system. Under this system produces a closed rectangular wing configuration the smallest induced drag for a predetermined span and height to span ratio. According to studies, the induced drag only 43% of that of a conventional airfoil, however this is dependent on the h / w ratio. Another advantage out savings on gasoline consumption, it follows from this is that the plane a shorter runway and a shorter runway needs.
A problem of the wing box configuration is the fact that there is a difference on the produced lift of the front and the rear due to the down wash of the front wing. This difference increases with increasing the angle of attack. The rear wing will create less lift so that more weight will fall on the front wing. This can be solved by setting a different angle of attack for both wings and thus trimming with the whole wing. However, this will affect the performances of the device.
Another 'problem' of the wing box configuration is the fact that the lift coefficient for the minimum amount of light is much higher in this type of aircraft than for a conventional aircraft having the same properties. Since both have the same weight and the same cruising speed, the lift will also be the same for both aircraft. The formula to calculate lift we can conclude that the wing box at higher altitudes will have cruising. This can cause problems for shorter flights and can cause adverse ecological impacts.
The wing-like design of the body thus provides increased lift to drag ratio resulting in lower operating costs, according to some sources, the use of gasoline can even drop to -50%. Further, it is also possible to build units with a much greater capacity to passengers or cargo. So think of a Boeing BWB design for a passenger capacity of 800 people, this is almost double that of a Boeing 747-800. As a result, the number of planes can be reduced at an airport, because there are fewer operations are required to provide the same number of passengers.
Some problems that should happen at this concept still occur. Such as the fact that it is very difficult to make a structural design that is not a tube or sphere, and yet is strong enough to be able to withstand the pressure at high altitudes. Furthermore, there is also the problem of the large taper ratio so that the danger of a stall is much greater during the landing and take-off with this device than in a conventional aircraft.
The concept of the D8 has some major differences from a conventional aircraft. To begin with, makes it either double-aisle design for an extra lift, which is created by the fuselage. This has the result that the wings can be reduced in size. The nose of this design also creates an upward effect trim so that the tail can be reduced even further since the downward pitching effect of the aircraft now partially compensated.
Subsequently, the wings of this concept 'unswept', ie they are in a near right angle to the fuselage, making the Mach number decreases unfortunately from 0.8 to 0.73. But this type of wings does have a higher aspect ratio which reduces the drag coefficient and increases the lift coefficient. Also, because the engines are now located on the back of the fuselage and hence to some extent to use the boundary layer of the fuselage as incoming air, this part of the carrier can already be neglected.
Finally, the horizontal and vertical tail wing, respectively, 28% smaller and 27% lighter and 50% smaller and 70% percent lighter. Since the motors are smaller determines the yaw-effect of these engines do not lower the size of the vertical tail plane, and as already explained, the trim nose upward effect of the nose, the reason for the smaller horizontal tail plane.