Single-stick control system for helicopters

Claim 1

Flight control for a helicopter with variable-pitch rotor blades, a power drive, and a throttle for controlling said power drive, which comprises first and second universal joints, each having companion members turnable about axes normal to and intersecting each other with a common center at said intersection, fixed bearings for pivotal support of one of said companion members of each joint about its axis, a tubular stick mounted with one end on the other companion member of said first joint for universal motion therewith, a shaft mounted in said stick for universal motion with said stick and for independent rotation therein, with said stick and shaft constituting operating elements, a handle carried by one of said operating elements for movement with said stick and being also independently movable thereon, an operative connection between said handle and shaft element for turning said shaft on independent movement of said handle, two first arms carried by said companion members, respectively, of said first joint for pivotal motion therewith, a second arm carried by said one companion member of said second joint for pivotal motion therewith, operating connections between said first arms and blades for cyclic control, and a first operating connection from said second arm to said blades, and a second operating connection from said second arm to said throttle for simultaneously controlling the collective pitch of said blades and said throttle.