ORNITHOPTER Russian patent published in 2012 - IPC B64C33/00 

FIELD: transport.

SUBSTANCE: proposed aircraft comprises fuselage with nose and tail sections, wings with ribs and skin, and engine with crankshaft provided with two symmetric journals. Fuselage tail section has horizontal tail unit made like bird tail to turn about aircraft lengthwise and crosswise axes. Every wing comprises MAIN outer wing corresponding to bird wing shoulder and elbow joints and made up of center wing section, peripheral section and intermediate section. Center wing section and peripheral sections comprise ribs. Note here that ribs of the former correspond to wing aerofoil and are secured by means of flat springs to allow turn of center wing section chord through 10-20 degrees. Peripheral section continues main wing section and comprises ribs made up of straight rods arranged at 30 to 60 degrees to aircraft lengthwise axis. Each journal of crankshaft is coupled with main outer wing section by flat pivot joint at point located at 1/10 of aircraft wing length from fuselage lengthwise axis. Crankshaft crank radius is selected to ensure center wing section angle of attack variation in the range of 15 to 30 degrees in upward and downward strokes, depending upon flight speed. Flat hinge pin is located on vertical axis connecting top and bottom dead centers of crankshaft. Hinge pin length is selected to ensure full angle of wing stroke making +/- 32 degrees. Center wing sections are flexibly jointed in nose and tail parts of fuselage.

EFFECT: higher flexibility of wings.

6 dwg