Idle Up

[scallybert]

Why should I use 'idle up', and what does it mean ?

[coptermanic]

For starters, you do not need to use it at all.
But it allows for a different range of blade pitch angles as opposed to NORMAL, and usually, we use a higher head speed too.

When you wish to start doing aerobatics etc, it is beneficial to have a higher head speed, and to set the 0 blade angle pitch position at "mid-stick'.
then full up = full +ve pitch
and full down = full -ve pitch
as long as we have set the Throttle and Pitch curves in the transmitter correctly.

Go watch the Helifreak Finless set-up vids for a fuller explanation.

[coptermanic]

....and with the throttle curve, it is either a "V" shape, eg 100/90/80/90/100 [for 5 point setup] or indeed a straight line eg 95/95/95/95/95.

So in essence the "idle position" which is not really idle at all , is either at the bottom of the throttle joystick, or at the mid-point for IDLE-UP, also called STUNT mode.

[Vanquish]

Why should I use 'idle up'

All the cool kids are doing it

and what does it mean ?

Your heli can do wicked cool stunts

[tourerjim]

If you do a search on here "idle up" your'll also find more explanations & poss video links.

[scallybert]

Ok, currently I hover mid-stick, so pitch is roughly 37.5, 50, 75, 100, 100.
(Effectively, minus a bit, 0, hover, full +ve, full +ve .)

I could easilly shift that to 0, 25, 50, 75, 100. For full +ve & -ve.

Why would I not just set normal mode to that ?

[sacko]

You can (I do, as I dont bother setting up normal mode really)

So that would give you full negative as well as positive pitch, now all you need is to keep your motor spinning (mirror of full throttle end point) to give you negative lift when inverted.

[scallybert]

....and with the throttle curve, it is either a "V" shape, eg 100/90/80/90/100 [for 5 point setup] or indeed a straight line eg 95/95/95/95/95.

My throttle curve is effectively redundant. It just tells the ESC that throttle hold is off.

I knock off throttle hold, and the ESC soft starts and auto spools up to what the heli manual describes as 3D head speed. Which it's governed to.

[scallybert]

All the cool kids are doing it

I like that answer, and I really hope you meant it the way I like it...

Your heli can do wicked cool stunts

In my case, it's the pilot that can't do the stunts...

I'm struggling to see why I wouldn't just have one mode, with a suitable head speed and full collective range.

[Vanquish]

Ok, currently I hover mid-stick, so pitch is roughly 37.5, 50, 75, 100, 100.
(Effectively, minus a bit, 0, hover, full +ve, full +ve .)

I could easilly shift that to 0, 25, 50, 75, 100. For full +ve & -ve.

Why would I not just set normal mode to that ?

You can use normal mode if you like, you just need a consistent throttle curve so when your upside down i.e negative pitch the heli doesnt lose power. You could run a 100,100,100,100,100 curve in normal mode and it would have the same effect as flicking the idle up switch. I like to be able to switch between a normal throttle curve of something like 0,25,50,75,100 for take off and landing and idle up of 100,100,100,100,100 (depending on the heli) for 3D flying.

[scallybert]

You can (I do, as I dont bother setting up normal mode really)

But why not just set up normal mode and fly in that ?

[sacko]

..because you cant go inverted.

At the bottom of the stick in normal mode you should have -2 (ish) pitch, with no power to the motor.

In idle up you would have full pitch and the desired max headspeed.

[scallybert]

You can use normal mode if you like, you just need a consistent throttle curve so when your upside down i.e negative pitch the heli doesnt lose power. You could run a 100,100,100,100,100 curve in normal mode and it would have the same effect as flicking the idle up switch.

The head speed is governed, and held ~constant throughout the flight.

I like to be able to switch between a normal throttle curve of something like 0,25,50,75,100 for take off and landing and idle up of 100,100,100,100,100 (depending on the heli) for 3D flying.

Why would you not just fly at a constant head speed ?

[BTW, I know little about nitro set-ups.]

[sacko]

Ok, so then as you said you need to alter your pitch curve to 0, 25, 50, 75, 100 to give you full pitch.

[scallybert]

..because you cant go inverted.

At the bottom of the stick in normal mode you should have -2 (ish) pitch, with no power to the motor.

In idle up you would have full pitch and the desired max headspeed.

At the bottom of the stick my normal mode has -2 (ish) pitch, and the motor runs at the governed head speed.

Advice seems to be *not* to have a curve like this, and a +/- max collective pitch curve. (ie different pitch curves can cause problems.)

So I set normal tp +/- max collective, and fly inverted in that.

Why not ?