Apparatus and method for increasing the angle of attack operating range of an aircraft

An apparatus for increasing the angle of attack operating range of an aircraft, comprising:

• a pair of substantially vertical tip fins, each having a main portion and an aft portion, said main portion securely connected to the tip of the aircraft wing and having a swept back leading edge, each leading edge of each said tip fins being swept back in an approximate range between 25.degree. and 50.degree. from a line perpendicular to the surface of said airplane wing, said aft portion comprising a substantially vertical aileron hingedly connected to said main portion of the tip fin for controlling the roll of said aircraft at high angles of attack, a hinge line being formed at said hinged connection being swept back, the sweeping back of said leading edge and said hinge line being such that at high angles of attack the oncoming airflow becomes nearly perpendicular to said leading edge and said hinge line thereby increasing the performance of the vertical tip fin when deflected.