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For ultimate safety, the Grasshopper employs a specially developed and patented arrangement, which is extremely simple in conception. The two see-saw rotor hub "beams" are constrained by a direct connecting linkage to remain parallel in elevation every time they align in the same azimuth. Kinematically, the mechanism is a parallel linkage, which contains a bearing so as to transmit the parallel motion from one direction of rotation to the other. 

This "transfer linkage", although simple in conception and execution, being the true logical extension of the semi-rigid principle to the contra-rotating configuration, called for many problems to be overcome before the mechanism was made safe and practical. The final arrangement of this device, as evolved from numerous tests, has proved itself capable of safe operation at relatively high wind speeds and under gusty conditions. It has thus been possible to reduce the safe separation distance between the rotors to an extent never before attempted in contra-rotating coaxial configurations.

The rotor control mechanism controls the pitch of each blade by rotation about its individual torsion hinge. The 'collective' pitch of the two blades in each rotor is varied simultaneously in both rotors for lift control. In order to tilt the rotors in the pitching or rolling sense, the pitch of the blades is controlled cyclically in accordance with conventional principles. The two rotors are tilted in parallel by carefully developed refinements of the cyclic control mechanism. 

In most of the earlier contra-rotating helicopters, directional control was achieved by changing the collective pitch of one rotor only. Such a directional control varies not only the torque but also the lift, and requires continuous co-ordination of the two controls by the pilot (as in a single-rotor configuration, too). 

The rotor control system of the Grasshopper was conceived so as to avoid this drawback. A pure directional control is achieved by simultaneously increasing the torque and lift of one rotor and decreasing those of the other. This aim and other considerations have led to a control mechanism wherein the interconnection between the two rotors is accomplished entirely in the non-rotating part of the mechanism.