Rotorcraft Flying Menu >Helicopter Flight Controls > Correlator / Governor

A correlator is a mechanical connection between the collective lever and the engine throttle. When the col-lective lever is raised, power is automatically increased and when lowered, power is decreased. This system maintains r.p.m. close to the desired value, but still requires adjustment of the throttle for fine tuning.

A governor is a sensing device that senses rotor and engine r.p.m. and makes the necessary adjustments in order to keep rotor r.p.m. constant. In normal operations, once the rotor r.p.m. is set, the governor keeps the r.p.m. constant, and there is no need to make any throttle adjust-ments. Governors are common on all turbine helicopters and used on some piston powered helicopters.

Some helicopters do not have correlators or governors and require coordination of all collective and throttle movements. When the collective is raised, the throttle must be increased; when the collective is lowered, the throttle must be decreased. As with any aircraft control, large adjustments of either collective pitch or throttle should be avoided. All corrections should be made through the use of smooth pressure.