R-22 -- Governor / Correlator

Philip Greenspun's Homepage : Philip Greenspun's Homepage Discussion Forums : Aviation : One Thread
Notify me of new responses
Will somebody please explain in detail what the difference is (in
operation, physical presence, etc.) between the governor and the
correlator in the Robinson R-22. Many thanks.
Mason (masonclewis@aol.com)

-- Mason Lewis, May 31, 2010

Answers

The correlator is a mechanical linkage that opens the throttle as the collective is raised and closes the throttle when the collective is lowered. You can watch the correlator in operation when the helicopter is shut down and parked in a hangar (raise collective and watch the throttle move back under the engine). The correlator does not use any feedback regarding the actual RPM of the engine/rotor.

The governor is an electronic circuit that watches the rotor RPM and twists the throttle slightly to push the rotor RPM back towards the ideal 101 percent. It will not operate with the helicopter powered off, nor will it operate with the RPM below 80 percent.

-- Philip Greenspun, June 4, 2010