VTOL aircraft with electric propulsion

1. A VTOL aircraft ( 1 ), comprising:

a fuselage ( 2 ) for transporting at least one of passengers or load;

a front wing ( 3 ) attached to the fuselage ( 2 );

a rear wing ( 4 ) attached to the fuselage ( 2 ), behind the front wing ( 3 ) and an aerodynamic center in a direction of forward flight (FF);

a right connecting beam ( 5 a ) and a left connecting beam ( 5 b ), said connecting beams ( 5 a , 5 b ) structurally connect the front wing ( 3 ) and the rear wing ( 4 ), said connecting beams ( 5 a , 5 b ) are spaced apart from the fuselage ( 2 ); and

at least two lifting units (M 1 -M 6 ) on each one of the connecting beams ( 5 a , 5 b ), said lifting units (M 1 -M 6 ) each comprise at least one propeller ( 6 b ) and at least one motor ( 6 a ) driving said propeller ( 6 b ), and are arranged with the respective propeller axis in an essentially vertical orientation (z);

wherein the front wing ( 3 ), at least in portions thereof, has a sweep angle γ between γ=45° and γ=135°, the rear wing ( 4 ) includes an outer rear wing section ( 4 a ) on each side of the fuselage ( 2 ) that as a whole has a forward sweep with sweep angle 30°≤β≤90°, and the rear wing ( 4 ) includes an inner rear wing section ( 4 b ) on each side of the fuselage that has a rearward sweep from the fuselage to the forward sweep portion of the outer rear wing section, the inner rear wing section forms a lateral stabilizing unit of the aircraft; and

wherein in a plane perpendicular to a longitudinal axis (x) of the aircraft ( 1 ), the rear wing ( 4 ) extends sideways from the fuselage ( 2 ) such that respective inner rear wing halves ( 4 b ) of the rear wing form an angle 90°≤θ≤100°, producing lateral stabilization of the aircraft.

2. The aircraft ( 1 ) of claim 1 , wherein the front wing ( 3 ) has a wing area (S front ) that is smaller than a wing area (S rear ) of the rear wing ( 4 ).

3. The aircraft ( 1 ) of claim 2 , wherein 60%<S front /S rear <100%.

4. The aircraft ( 1 ) of claim 1 , wherein the rear wing ( 4 ) is partly shaped as a V-Tail with a sweep angle (δ) greater than 90°.

5. The aircraft ( 1 ) of claim 1 , wherein the at least two lifting units (M 1 -M 6 ) on each one of the connecting beams comprises three of the lifting units (M 1 -M 6 ) on each one of the connecting beams ( 5 a , 5 b ).

6. The aircraft ( 1 ) of claim 1 , wherein the lifting units (M 1 -M 6 ) are placed symmetrically about a longitudinal (x-z) and a lateral (y-z) plane, respectively, of the aircraft ( 1 ).

7. The aircraft ( 1 ) of claim 1 , wherein attachments (A 3 , A 4 ) of the front wing ( 3 ) and the rear wing ( 4 ), respectively, to the connecting beams ( 5 a , 5 b ) are placed in between respective rotor planes (P 1 -P 6 ) swept by the propellers ( 6 b ).

8. The aircraft ( 1 ) of claim 1 , wherein the rear wing ( 4 ) is placed higher in vertical position (z) than the front wing ( 3 ).

9. The aircraft ( 1 ) of claim 1 , wherein the front wing ( 3 ) incorporates a dihedral angle (λ).

10. The aircraft ( 1 ) of claim 9 , wherein the dihedral angle (λ) is incorporated at respective tips of the front wing ( 3 ).

11. The aircraft ( 1 ) of claim 1 , wherein the outer rear wing section ( 4 a ) incorporates an anhedral angle (ε) towards said connecting beams ( 5 a , 5 b ).

12. The aircraft ( 1 ) of claim 1 , wherein longitudinal aircraft stability, which is defined by a quantity Cm/α, is negative, Cm being a pitching moment coefficient and a being an angle of attack.

13. The aircraft ( 1 ) of claim 1 , wherein a centre of actuation (CoA) is geometrically in a same longitudinal position (x CoA ) as a centre of gravity (CoG) of the aircraft, and a neutral point (NP) is located aft of both the centre of actuation (CoA) and the centre of gravity (CoG).

14. The aircraft ( 1 ) of claim 1 , further comprising at least one forward propulsion unit (F 1 , F 2 ) connected thereto.

15. The aircraft ( 1 ) of claim 14 , wherein the at least one forward propulsion unit includes at least one propeller and at least one motor driving said propeller.

16. The aircraft ( 1 ) of claim 15 , wherein the at least one motor is an electric motor.

17. The aircraft ( 1 ) of claim 14 , wherein the at least one forward propulsion unit (F 1 , F 2 ) includes one of the forward propulsion units located on each side of the fuselage ( 2 ).

18. The aircraft ( 1 ) of claim 17 , wherein the forward propulsion units are located below both the front wing ( 3 ) and the rear wing ( 4 ) and forward of the rear wing ( 4 ).

19. The aircraft ( 1 ) of claim 1 , wherein the front wing ( 3 ) and the rear wing ( 4 ), when viewed along a longitudinal axis (x) of the aircraft ( 1 ), together form a closed loop shape.