US 11,932,380 B2
Vibration isolation systems for compound helicopters
Frank Bradley Stamps, Colleyville, TX (US); Michael Reaugh Smith, Colleyville, TX (US); and Bradley Joseph Passe, Irving, TX (US)
Assigned to Textron Innovations Inc., Providence, RI (US)
Filed by Textron Innovations Inc., Providence, RI (US)
Filed on Jan. 21, 2021, as Appl. No. 17/154,925.
Application 17/154,925 is a continuation in part of application No. 16/716,264, filed on Dec. 16, 2019, granted, now 11,214,362.
Application 16/716,264 is a continuation in part of application No. 15/459,781, filed on Mar. 15, 2017, abandoned.
Prior Publication US 2021/0403148 A1, Dec. 30, 2021
Int. Cl. B64C 27/22 (2006.01); B64C 27/00 (2006.01); B64C 27/10 (2023.01); B64C 27/26 (2006.01); F16F 15/167 (2006.01)
CPC B64C 27/001 (2013.01) [B64C 27/10 (2013.01); B64C 27/22 (2013.01); B64C 27/26 (2013.01); F16F 15/167 (2013.01); B64C 2027/002 (2013.01); F16F 2222/08 (2013.01); F16F 2228/066 (2013.01); F16F 2230/18 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A compound helicopter comprising:
a fuselage including a fuselage airframe;
a translational thrust system coupled to the fuselage airframe;
a pylon assembly subject to vibration, the pylon assembly including a transmission and a rotor system having a main rotor assembly;
a main rotor vibration isolation system including a plurality of augmented liquid inertia vibration eliminator units each having an isolation frequency and each coupled between the fuselage airframe and the pylon assembly to reduce transmission of the pylon assembly vibration to the fuselage airframe at the isolation frequency, each augmented liquid inertia vibration eliminator unit including at least one active tuning element movable to tune the isolation frequency thereof;
a wing subject to rotorwash-induced vibration from the main rotor assembly, the wing including a wing airframe; and
a wing vibration isolation system including a plurality of links coupled between the wing airframe and the fuselage airframe, each link including a liquid inertia vibration eliminator unit configured to reduce transmission of the rotorwash-induced wing vibration to the fuselage airframe, the plurality of links comprising a plurality of parallel and vertically-oriented links including at least one left link and at least one right link and at least one diagonally-oriented lateral link interposed between the at least one left link and the at least one right link.