Aircraft with right and left propulsion unit support beams extending between main and aft wings

1. A VTOL aircraft ( 1 ), comprising:

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

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

an aft wing ( 4 ) attached to the fuselage ( 2 ), behind the front wing ( 3 ) 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 aft wing ( 4 ), said connecting beams ( 5 a , 5 b ) are spaced apart from the fuselage ( 2 ); and

at least three propulsion units ( 6 ) on each one of the connecting beams ( 5 a , 5 b ), said propulsion units ( 6 ) each comprise at least one propeller ( 6 b , 6 b ′) and at least one motor ( 6 a ) driving said propeller ( 6 b , 6 b ′), and the propellers are arranged with respective propeller axes thereof in an essentially vertical orientation (z), with the propellers on each one of the connecting beams ( 5 a , 5 b ) being located at different heights in the essentially vertical orientation (z), a respective height of the propellers on each one of the connecting beams ( 5 a , 5 b ) increasing from front to rear, and the at least three propulsion units are each arranged directly on each one of the connecting beams.

2. The aircraft ( 1 ) according to claim 1 , wherein the at least three propulsion units ( 6 ) on each of the connecting beams are arranged behind each other in the direction of forward flight (FF).

3. The aircraft ( 1 ) according to claim 1 , further comprising at least one of:

the connecting beams ( 5 a , 5 b ) extend in the direction of forward flight (FF) beyond the front wing ( 3 ), and at least one of the propulsion units ( 6 ) on each side is located on a respective one of the connecting beams ( 5 a , 5 b ) in front of the front wing ( 3 ) in the direction of forward flight(FF); or

the connecting beams ( 5 a , 5 b ) extend beyond the aft wing ( 4 ) in a rearward direction, and at least one of the propulsion units ( 6 ) on each side is located on a respective one of the connecting beams ( 5 a , 5 b ) behind the aft wing ( 4 ).

4. The aircraft ( 1 ) according to claim 1 , wherein the connecting beams ( 5 a , 5 b ) extend parallel to the forward flight direction (FF).

5. The aircraft ( 1 ) according to claim 1 , wherein a distance between the connecting beams ( 5 a , 5 b ) decreases at least in a direction toward a rear of the aircraft ( 1 ) in the direction of forward flight (FF).

6. The aircraft ( 1 ) according to claim 1 , wherein, in the direction of forward flight (FF) or opposite thereto, a distance between a propeller axis of the vertically oriented propulsion units ( 6 ) and any one of the front ( 3 ) and the aft wings ( 4 ) is at least as large as a radius of the corresponding propeller ( 6 b , 6 b ′).

7. The aircraft ( 1 ) according to claim 1 , wherein a center of gravity (CoG) of the aircraft ( 1 ) is located between the front wing ( 3 ) and the aft wing ( 4 ) with respect to the direction of forward flight (FF), and a lifting center (LC) of the aircraft ( 1 ) is located aft the center of gravity (CoG) with respect to the direction of forward flight (FF).

8. The aircraft ( 1 ) according to claim 1 , wherein rotor diameters of the vertically oriented propellers ( 6 b , 6 b ′) are between 10% <D<35% of an overall dimension, D, of the aircraft ( 1 ), wherein D is a diameter of an imaginary circle that encompasses the aircraft ( 1 ), when looking along a yaw axis (z) thereof.

9. The aircraft ( 1 ) according to claim 1 , wherein the at least three of the propulsion units ( 6 ) are vertically oriented on each one of the connecting beams ( 5 a , 5 b ), with two front-most and two aft-most ones of the propulsion units having middle ones of the propulsion units located therebetween and the propellers ( 6 b ) of two front-most and two aft-most of the propulsion units ( 6 ), respectively, have a larger diameter than the propellers ( 6 b ′) of the middle ones of the propulsion units ( 6 ).

10. The aircraft ( 1 ) according to claim 1 , wherein the motors are electric motors.

11. The aircraft ( 1 ) according to claim 1 , wherein the aft wing ( 4 ) is a box-wing, comprising an upper aft wing ( 4 a ) and a lower aft wing ( 4 b ), said upper and lower aft wings ( 4 a , 4 b ) are arranged distanced to each other in a direction along a vertical or yaw axis (z) of the aircraft ( 1 ) and are structurally connected by at least one outer vertical stabilizer ( 8 b ) located at corresponding ends of the upper aft wing ( 4 a ) and the lower aft wing ( 4 b ), respectively.

12. The aircraft ( 1 ) according to claim 11 , wherein the lower aft wing ( 4 b ) is mechanically connected to a rear part of the fuselage ( 2 ), in the direction of forward flight (FF), and the upper aft wing ( 4 a ) is connected to the rear part of the fuselage ( 2 ) via at least one inner vertical stabilizer ( 8 a ).

13. The aircraft ( 1 ) according to claim 11 , wherein the lower aft wing ( 4 b ) is symmetrical in a leading-to-trailing edge cross section, with less airfoil inclination with respect to the direction for forward flight (FF) than the front wing ( 3 ) and the upper aft wing ( 4 a ).

14. The aircraft ( 1 ) according to claim 1 , further comprising at least one propulsion unit ( 9 ) for forward propulsion arranged at a rear of the fuselage ( 2 ) in the direction of forward flight (FF).

15. The aircraft ( 1 ) according to claim 14 , wherein the at least one propulsion unit ( 9 ) for forward propulsion is located in front of a leading edge of the aft wing ( 4 ).

16. The aircraft ( 1 ) according to claim 14 , wherein there are two of the propulsion units ( 9 ) for forward propulsion, with one being located on a right side of the fuselage and another being located on a left side of the fuselage ( 2 ), respectively.

17. The aircraft ( 1 ) according to claim 14 , wherein a diameter (d) of the propeller ( 9 b ) of the at least one propulsion unit ( 9 ) for forward propulsion is dimensioned smaller than the propellers ( 6 b ) of the vertically oriented propulsion units ( 6 ), and have about 20%-80% of a diameter (d′) of the propellers ( 6 b ) of the vertically oriented propulsion units ( 6 ).

18. A VTOL aircraft ( 1 ), comprising:

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

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

an aft wing ( 4 ) attached to the fuselage ( 2 ), behind the front wing ( 3 ) 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 aft wing ( 4 ), said connecting beams ( 5 a , 5 b ) are spaced apart from the fuselage ( 2 );

at least three propulsion units ( 6 ) on each one of the connecting beams ( 5 a , 5 b ), said propulsion units ( 6 ) each comprise at least one propeller ( 6 b , 6 b ′) and at least one motor ( 6 a ) driving said propeller ( 6 b , 6 b ′), and the propellers are arranged with respective propeller axes thereof in an essentially vertical orientation (z), with the propellers on each one of the connecting beams ( 5 a , 5 b ) being located at different heights in the essentially vertical orientation (z), a respective height of the propellers on each one of the connecting beams ( 5 a , 5 b ) increasing from front to rear; and

wherein the connecting beams rise or slant upwards from the front to the rear of the aircraft in a vertical direction.