tsagi has long been aware of the advantages of forward-swept wings, with research including the development of the tsibin ll and study of the captured junkers ju 287 in the 1940s. at high angles of attack, the wing tips remain unstalled allowing the aircraft to retain aileron control. conversely to more conventional rear-swept wings, forward sweep geometrically creates increased angle of incidence of the outer wing sections when the wing bends under load. the wings experience higher bending moments, leading to a tendency for the wings to fail structurally at lower speeds than for a straight or aft-swept wing.