L3Harris Workhorse, the FVR Quad, has Yaw Authority

The FVR platform is certainly an impressive accomplishment. According to its maker, “The FVR is designed for long endurance, 12 to 18 hours, with an 8 to 22 pound payload capacity.”(https://www.l3harris.com/all-capabilities/fvr-90-airframe)

According to the patent, large quad platforms are great at their VTOL thing, but have little yaw authority. To make a quad more agile, L3Harris came up with a solution: orient propellers at an angle to the horizontal. This way, you can have a bit more push to yaw the drone.

The inventors took several approaches to this concept. One approach is to have a second set of ‘thrust rotors’ under the regular props that are set to an angle.

Another idea is a tricopter with “pivoting engine pods [that] can each be actuated to position each one of thrust rotors 110–113 in horizontal position relative the inwardly and outwardly tilted positions.”

Claim 1: “A vertical take-off and landing aircraft, comprising: a fixed wing airframe having first and second wings extending from first and second sides, respectively, of a fuselage having a leading extremity and a trailing extremity, and a tail assembly located behind the trailing extremity; a forward thrust rotor mounted to the airframe for providing forward thrust to the aircraft; vertical take-off and landing (VTOL) thrust rotors mounted to the airframe for providing vertical lift to the aircraft, the VTOL thrust rotors include a first set of VTOL thrust rotors proximate to the first side of the fuselage and a second set of VTOL thrust rotors proximate to the second side of the fuselage; the VTOL thrust rotors of the first set of VTOL thrust rotors are identically laterally tilted to a lateral tilt with respect to the fuselage; the VTOL thrust rotors of the second set of VTOL thrust rotors are identically laterally tilted to a lateral tilt with respect to the fuselage; and the lateral tilt of the VTOL thrust rotors of the first set of VTOL thrust rotors is the mirror image of the lateral tilt of the VTOL thrust rotors of the second set of VTOL thrust rotors; wherein the VTOL thrust rotors receive control inputs to increase or decrease the thrust of one or more of the VTOL thrust rotors independently of the other VTOL thrust rotors and the forward thrust rotor to effect independent control of the roll, pitch, yaw, and vertical thrust of the aircraft independent of differential torque between pairs of the VTOL thrust rotors that is augmented by lateral thrust components associated with the lateral tilt of the VTOL thrust rotors during lifting of the aircraft to increase yaw control, and further wherein the forward thrust rotor is activated independently of the VTOL thrust rotors to provide forward thrust of the aircraft during flight.”

Title: “Vertical Take-off And Landing Aircraft With Rotor Thrust Yaw Control”

US Patent No: 11485488 

Filed (US Prov.): 2014-12-07

Granted: 2022-11-01

Applicant: L3HARRIS LATITUDE LLC