Granted Patent B2

US 12,491,995 · App. 18/440,931 · Granted Dec 9, 2025

Inventors: Gregor Čretnik (Ljubljana, SI); David Eržen (Ljubljana, SI); Rok Lapuh (Ljubljana, SI); Andres Žnidar (Vrhnika, SI); Tine Tomažič (Vrhnika, SI); Blaž Močan (Ljubljana, SI); Jernej Drofelnik (Ljubljana, SI); Jernej Pirnar (Tržič, SI); Tadej Kosel (Komenda, SI); Antonio Righetti (Farra d'Isonzo, IT); Thomas Koopman (Ljubljana, SI); Matej Andrejašič (Postojna, SI)

Assignee: Pipistrel d.o.o.

B64C29/0025

Abstract

Claims (46)

1 . A vertical takeoff and landing (VTOL) aircraft, comprising:

a fuselage aligned longitudinally;

a forward wing that extends laterally across a bottom portion of the fuselage;

an aft wing that extends laterally across an upper portion of the fuselage;

a right longitudinal boom that extends longitudinally outboard of a right side of the fuselage beneath the forward wing and the aft wing;

a left longitudinal boom that extends longitudinally outboard of a left side of the fuselage beneath the forward wing and the aft wing;

a right tail that extends vertically upwards from the right longitudinal boom to the aft wing;

a left tail that extends vertically upwards from the left longitudinal boom to the aft wing;

a maximum takeoff weight (MTOW) of about 1700-kg, wherein the VTOL aircraft is capable of

flying at about 80-knots equivalent airspeed (EAS) to about 100-knots EAS during a cruise phase of flight, flying for a range of about 300-km, and flying for

a flight time of about 4-hours; and

at least one pair of rotors configured to provide vertical thrust and mounted on top of the pair of longitudinal booms, respectively, wherein each rotor of the at least one pair comprises:

an about 2-meter propeller diameter;

a disk loading of about 67-kg/m 2 to about 110-kg/m 2 ; and

an operating speed of about 1800 rotations-per-minute (RPM) to about 2700-RPM; and

a pusher propeller located on an aft end of the fuselage, wherein the pusher propeller is configured for pushing the aircraft forward during forward flight.

2 . The VTOL aircraft of claim 1 comprising a forward wing configured to provide a wing loading of about 44-kg/m 2 to about 68-kg/m 2 during level-steady flight.

3 . The VTOL aircraft of claim 1 comprising an aft wing configured to provide a wing loading of about 48-kg/m 2 to about 70-kg/m 2 during level-steady flight.

4 . The VTOL aircraft of claim 1 , wherein the aircraft is capable of flying a maximum range of up to about 1500-km.

5 . The VTOL aircraft of claim 1 , wherein the aircraft is capable of flying for a maximum flight time of up to about 9-hours.

6 . The VTOL aircraft of claim 1 , wherein a disk loading is at least about 90-kg/m 2 when six rotors are functioning at a time.

7 . The VTOL aircraft of claim 1 , wherein the at least one pair of rotors each comprise an electric motor.

8 . The VTOL aircraft of claim 1 , wherein the pusher propeller has a propeller diameter of about 2-meters.

9 . The VTOL aircraft of claim 1 , comprising a pair of aft booms each extending aft from a respective tail of the pair of tails and aft of the aft wing.

10 . The VTOL aircraft of claim 9 , comprising a pair of aft tail stabilizers, each extending upwards from and operatively coupled to one of the pair of aft booms, respectively.

11 . The VTOL aircraft of claim 9 , comprising an aft pair of rotors configured to provide vertical thrust, wherein each of the aft pair of rotors is mounted on top of one of the pair of aft booms, respectively.

12 . A method of operating a vertical takeoff and landing (VTOL) aircraft, comprising:

providing vertical thrust during lift off with at least one pair of rotors, comprising:

rotating the at least one pair of rotors at a speed of 1800 rotations-per-minute (RPM) to 2700-RPM; and

operating the at least one pair of rotors with a disk loading of 67-kg/m2 to 110-kg/m2;

lifting off with a takeoff weight less than a maximum takeoff weight (MTOW) of 1700-kg; and

flying during a cruise phase of flight with a speed of 80-knots equivalent airspeed (EAS) to 100-knots EAS, a forward wing loading of 44-kg/m2 to 68-kg/m2, and an aft wing loading of 48-kg/m2 to 70-kg/m2;

wherein the VTOL aircraft comprises:

a fuselage aligned longitudinally;

a forward wing that extends laterally across a bottom portion of the fuselage;

an aft wing that extends laterally across an upper portion of the fuselage;

a right longitudinal boom that extends longitudinally outboard of a right side of the fuselage beneath the forward wing and the aft wing;

a left longitudinal boom that extends longitudinally outboard of a left side of the fuselage beneath the forward wing and the aft wing;

a right tail that extends vertically upwards from the right longitudinal boom to the aft wing;

a left tail that extends vertically upwards from the left longitudinal boom to the aft wing; and

a pusher propeller located on an aft end of the fuselage, wherein the pusher propeller is configured for pushing the aircraft forward during forward flight; and

wherein the at least one pair of rotors are mounted on top the longitudinal booms.

13 . The method of claim 12 comprising operating three pairs of rotors with a disk loading of at least 90-kg/m 2 .

14 . The method of claim 12 , wherein flying comprises propelling forward using a pusher propeller.

15 . The method of claim 14 comprising powering the pusher propeller via a combustion engine.

16 . The method of claim 12 comprising landing on the ground vertically during a landing phase of flight via the at least one pair of rotors.

Assignments (1)

Continuity (1)

References Cited (20)