Rotor blade spacing for vibration attenuation
A rotor system for a rotorcraft, the rotor system is a rotor hub having six rotor blades attached to a rotor mast via a rotor yoke assembly. Each rotor blade is angularly spaced in 30° and 90° alternating angular increment about a mast axis of rotation. Such rotor blades spacing reduces the vibration that is translated into the rotorcraft through the rotor mast.
1. A rotor system for a rotorcraft, comprising:
a rotor hub having six rotor blades;
wherein each rotor blade is angularly spaced in 30° and 90° alternating angular increments about a mast axis of rotation for vibration attenuation.
2. The rotor system according to claim 1 , wherein the rotor blades rotate in a single direction about the mast axis of rotation.
3. The rotor system according to claim 1 , wherein the rotor blades are located in a single plane transverse to the mast axis of rotation.
4. The rotor system according to claim 3 , wherein the rotor blades are attached to a rotor mast via a rotor yoke assembly.
5. The rotor system according to claim 1 , wherein three of the rotor blades are located in an upper plane while the remaining three rotor blades are located in a lower plane, each plane being transverse to the mast axis of rotation.
6. The rotor system according to claim 5 , wherein the three rotor blades located in the upper plane are attached to a rotor mast via an upper rotor yoke assembly, while each of the three rotor blades located in the lower plane are attached to the rotor mast via a lower rotor yoke assembly.
7. A rotorcraft, comprising:
a fuselage; and
a rotor hub having six rotor blades;
wherein each rotor blade is angularly spaced in 30° and 90° alternating angular increments about a mast axis of rotation for vibration attenuation.
8. The rotorcraft according to claim 7 , wherein the rotor blades rotate in a single direction about the mast axis of rotation.
9. The rotorcraft according to claim 7 , wherein the rotor blades are located in a single plane transverse to the mast axis of rotation.
10. The rotorcraft according to claim 9 , wherein the rotor blades are attached to a rotor mast via a rotor yoke assembly.
11. The rotorcraft according to claim 7 , wherein three of the rotor blades are located in an upper plane while the remaining three rotor blades are located in a lower plane, each plane being transverse to the mast axis of rotation.
12. The rotorcraft according to claim 11 , wherein the three rotor blades located in the upper plane are attached to a rotor mast via an upper rotor yoke assembly, while each of the three rotor blades located in the lower plane are attached to the rotor mast via a lower rotor yoke assembly.
13. The rotorcraft according to claim 7 , wherein the rotorcraft is at least one of a helicopter, a tandem rotor helicopter, a tiltrotor aircraft, a four-rotor tiltrotor aircraft, a tilt wing aircraft, and a tail sitter aircraft.