r22 clutch
Dear all
premitting that i am not an heli pilot but that i am very intrigued by them, surfing the net i came across an article about the r22.
Now it is my understanding that power is transferred from the engine to the main rotor system via two dual V belts running on an upper sheave and on a lower sheave driven by an electric gear motor controlled by the CLUTCH switch.
For start up, to prevent the starter from having to overcome the load of the main rotor, the upper sheave is lowered towards the lower one loosing the belts while as the engine spools up as the CLUTCH switch is flipped to the ENG position, the gear motor drives the upper sheave up and away from the lower one, towards the in-flight position, tightening the belts and bringing the load of the main rotor system onto the engine, as reflected by an increase of RRPM’s.
Thereafter the gear motor is controlled by a pressure sensing switch in such a manner to keep the belts in tension at all times as they warm up and stretch.
At engine shutdown the top sheave is lowered again towards the lower sheave loosing the belts and releasing the engine from the load of the main rotor system.
My questions are:
when must the clutch be engaged? is there a minimum ERPM and what do you check once you engage it - RRPM, engine and rotor needles matching-?
What is the function of the CLUTCH warning light? does it ever illuminate in flite?
Which means do you have to monitor the clutch?
How is related to the rotor brake?
When do you disengage the clutch?
If you have to add anything to the clutch topic, please do so.
Many thanks
Baobab