Conceptual design of a medium size flying wing

Abstract

Flying wings are one of the most promising concepts regarding the ever-increasing air traffic demand. Furthermore, they help improving economic efficiency and are environmentally friendly, both in terms of emissions and noise. In the first place, the paper deals about the initial design of a medium size C-type flying wing, of the 300-seat class, showing that the aircraft is operationally efficient, and can beat conventional airplanes of similar capacity. It specifically exhibits some considerable gains in field and cruise performances. Second, the paper addresses the potential of some emerging technologies, such as laminar flow control, vectored thrust, and active stability, which provide additional improvements and allow the simplification of the original configuration to a U-type arrangement. A preliminary assessment of emergency evacuation is included.

Design of a high altitude long endurance flying-wing solar-powered unmanned air vehicle

“…The maximum camber location has a strong in §uence on the pitching moment and a slight e¨ect on drag polar; so, it can be used to compensate for the lift reduction resulting from the use of a re §exed aerofoil section. The spanwise twist distribution does not give enough help in terms of stability with these types of aerofoil section [14,15]; selecting a suitable combination of sweep and twist distribution to generate zero pitching moment (with a slightly-re §exed aerofoil section) [16,17]; using a suitable dihedral angle (or dihedral distribution) could add some enhancement in the lateral direction [18]; and using winglets or C-wings to reduce induced drag and add further directional stability and control [19,20].…”

Cost-range trade-off of intermediate stop operations of long-range transport airplanes

“…The original route will be lengthened by some detour and split into two parts: a first one with 55% the original distance; and a second segment with the rest of the trip. Equations (11), (15) and (16) determine the amounts of fuel needed for the first flight, second flight and overall trip, respectively. This has to be compared to the original trip fuel, computed with equation (7), for the same payload and city pair distance.…”

“…How will the evolving air traffic management affect the overall efficiency of the air transportation system? Two distinct approaches can be followed to answer these questions: pursuing the improvement of the current airplane layout and air traffic system or adopting a more radical perspective by incorporating new configurations, such as blended-wing-bodies [12][13][14][15] and joinedwings 16 with the corresponding air traffic rules.…”

Optimization of planform and cruise conditions of a transport flying wing

“…The main features of the C-type flying wing used in the present research are described in detail in reference [20]. Its initial specifications correspond to a common long-range mission: 10 000 km with a full passenger load (around 250-300 passengers) at high subsonic speed (Mach number between 0.8 and 0.85).…”

“…Structurally, the flying wing is arranged as a dual entity: an unconventional inner wing with a pressurized torque box between the spars, for passenger cabins and holds, and an outer wing with fairly conventional architecture, including fuel tanks outboard of the cargo holds. The inner wing is arranged as a vaulted double-skin, ribbed shell that behaves very well in terms of weight saving, load diffusion, and fail-safe features [11,19,20]. Figure 2 shows the internal cabin arrangement in a three-class seating for about 250 passengers.…”