In the United States, Jack Northrop championed the flying wing, culminating in the piston-powered XB-35 and the jet-powered YB-49. Although these aircraft demonstrated incredible range and payload capabilities, they suffered from marginal directional stability and structural pitching oscillations, leading to the cancellation of the programs in the late 1940s. The Fly-by-Wire Revolution
Tailless wings must be stiff enough to resist twisting under high aerodynamic loads, yet flexible enough to optimize aerodynamic performance. Because pitch control surfaces sit directly on the wing trailing edge, any structural twisting (torsion) of the wing can lead to control reversal. For example, deflecting an elevon downward to increase lift might twist the entire wingtip downward instead, causing a net loss of lift. High-modulus carbon fiber composites are mandatory in modern designs to tailor directional stiffness without adding prohibitive weight. 5. Modern Applications and Future Trends tailless aircraft in theory and practice pdf
Standard airfoils have a camber line that curves downward, creating a negative (nose-down) pitching moment. A reflexed airfoil features a trailing edge that curves slightly upward. This upward curve generates a local downward force at the rear of the profile, creating a positive (nose-up) pitching moment that can trim the aircraft without a tail. However, reflexed airfoils generally suffer from lower maximum lift coefficients ( CLmaxcap C sub cap L sub m a x end-sub ) compared to conventional airfoils. In the United States, Jack Northrop championed the
Conversely, the lack of a cylindrical fuselage severely limits internal volume. Thick airfoil profiles are required to house passengers, cargo, fuel tanks, and landing gear. Because pitch control surfaces sit directly on the