Throttle-swash mixing

[t-rex pedro]

Do you guys dial in throttle-swash mix when running a governor or is this only for non governed set ups?

[moonmanflyer]

Not me mate, i leave all the programme mixes alone

[jamiem]

i think i run about 15% ail and ele to throttle. makes it fly much nicer if your gov fails for any reason

[richieclarkie]

I use cyclic to TH mixes because by my understanding is the Govenor(revlok) sees the throttle input created by the mix and take it into account. However I was told this by Ade (I think). He may be able to shed light on this better than me.

I've never backed to backed it to see whether it makes a difference.

[Steve]

Don't forget rudder to throttle mix as well.

You've only got one power source, one engine. So every time you input a cyclic or rudder command, you are sapping power from the engine to make that control happen, and reducing the oooomph being transmitted to the main head rotation.

I have used all the mixes to varying extents on non-governed helis.

[flatspins]

I used mixing untill I started running a govenor.

I use the revlock 20 now, and don't use any throttle mixing on my IC models.

On my electrics, I use about 10%-15% mixing.
You just have to fly it and dial in the right amout for each individual model.

[t-rex pedro]

I have used all the mixes to varying extents on non-governed helis.

But is the same true for governed helis?

[Steve]

But is the same true for governed helis?

A governor works in harmony your throttle curves to manage the head speed, so good throttle servo control usually makes the governor more efficient and accurate. So yes in theory, but it might be hard to spot the difference.

A limiter only limits the head speed and only takes over the throttle control when the head speed exceeds the set value. That's why many people set their throttle curve to 100% flat line with limiters as it makes the head speed continuously high, therefore the limiter is permanently engaged. So, if you're using this setup then I suppose you wouldn't need the throttle mixing.

[moyesboy]

Governors come in two types. Active governors (Youngblood ATG, CSM revlock etc), and reactive type (futaba).

Reactive governor
The reactive type was the first available. The governor is independant of the throttle channel, once switched on it controls the throttle servo via the rpm sensor and opens the throttle if it sees the rpm drop. There is always a lag becuase it can't open the throttle until it sees the drop in rpm. The problem is that by the time the throttle is open the motor may have fallen off its power band and find it hard to recover.
Some pilots prefeerred no govenor becuase with throttle curves the throttle would open immediately with the collective - but this didn't solve the problem of overspeeding during descents and decellerations.

Limiters then got popular. The correct theroetical use was to use a conventional throttle curve and then the limiter would prevent the overspeeding when it ocurred. The throttle would still open immediately as per the throttle curve. Some folks run these as a flat line but this shouldn't work better than a convential throttle curve biased a bit high and runs the risk of the motor going full chat if the sensor fails, until you switch the governor off.

Active governors
These allow the throttle curve to pass through to the throttle servo, so you still get the throttle opening as son as you move the stick. however the governor is working on top of that and controlling the difference between the measured rpm and the desired rpm. When combined with an accurate throttle curve the control system is much more accurate and responsive. It will benefit from cyclic to throttle mixing becuase then it will be controlling even less of an error in rpm after this throttle compensation from the cyclic applied.

The other mix that is popular is the rudder to governor rpm mix. This lets you compensate the rotor rpm for the yaw rate. Left hand piroette normally causes a loss in height in the hover, while right hand makes it climb. mixing rudder to gov rpm can compensate for that. I think this one would be more useful than a direct rudder to throttle mix but I haven't tried it.
I had cyclic throttle mixing on my raptor with revlock 20, but haven't got round to doing it on my current two nitro helis.