VARIABLE-DIAMETER TILT ROTOR HAVING DISPLACED TWIST ANGLE AND METHOD OF ENHANCING EFFICIENCY OF IMPARTING FORWARD MOTION TO FLYING VEHICLE

摘要

FIELD: aeronautical engineering. SUBSTANCE: tilt rotor has inner section 11 having linear twist angle from tip of root 12 as far as its outer tip 13 and outer section 14 telescopically moved over inner section 11 which is additionally provided with linear twist angle from tip of root 17 as far as its outer end. Outer section 14 is shifted by approximately 4 to 15 deg relative to inner section 11 to ensure stepped change of twist angle when blade is in extended position; main rotor may operate at large blade angles during helicopter mode without premature flow break-away along inner surfaces of aerodynamic profile, thus providing for effective operation at large thrust coefficient/solidity ratios. Trailing edge of outer section may not turn along 30-percent tail portion of chord of section of aerodynamic profile to ensure equivalent increase of angle of twist in displacement in engagement between blade sections. During cruise flight at forward motion, inner equivalent increment of twist angle ensures operation of inner sections of aerodynamic profile at larger blade angles for reduction of areas of negative lift and enhancing efficiency of imparting forward motion at cruise flight. EFFECT: enhanced efficiency.