Throttle trim for engine idle

[chris231]

I've got my Whiplash gasser flying roughly how I want it.
Am using a spektrum TX (DX18) with HC3-SX helicommand.
Since it's Flybarless, I have disabled the trims in the TX to stop me accidentally moving them.

On my normal throttle curve I have the low point set to 16% for the engine to start and idle at.

However depending on the weather (very variable at the mo) sometimes I have to move the point up or down (a bit) to get it to idle at the right speed.
This is slightly annoying when I could just use a trim to move it up or down quickly.

I'd also like if poss for my throttle curve to start at 0% which would be idle.

I tried re-enabling the throttle trim, but this trim only seems to operate once the stick is move up off the bottom, where as I need it to actually operate at the bottom of the stick travel ONLY.

Since this is my first engined heli (in a very long time), am I just going about this all wrong and should just start my throttle curve at 16%, like I'm already doing?

The throttle linkage is setup as in the manual, and the heli works nicely set like this, so don't really want to mess with it mechanically if poss.

Any idea appreciated,
Thanks
Chris

[mole hunter]

Hi Chris, You sure have jumped in at the deep end after a long lay off and got yourself a beast of a bird. I did a similar thing last year and got a Vario Benzin trainer having only small electric prior to. I'm not familiar with the DX18 or Hellicommand but can you not enable only the throttle trim tab or could you dial in a slightly higher idle on IU 1 and another curve on IU 2? The Wippy seems to have a big following in the USA and I dip into the Gasser section on the Freak. Carey Shurley - HE DER MAN Gas Powered Thoughts - HeliFreak Cheers, Marty

[NoFixedAbode]

Re: Throttle trim for engine idle

I have a dx8 so assume that dx18 is the same regarding throttle trim and it does NOT alter trim for pitch. So re enable throttle trim. Don't use curve for tickover. Set it up manually then use trim for tickover.

P.s. hc3 is not relevant as throttle is only a pass through.

[chris231]

Thanks for that.
Will give it a try.
Going to wire out the governor for this test, to minimise any unwanted interaction.

And yeah it flies great. Quite scary after my main heli being an align 450.
Used to fly a moskito years ago. Things are v different from back then.

[Telehandler]

isnt 16% high for engine idle? might be worth going through throttle linkage setup again

[chris231]

Managed to sort it thanks guys.
Shortened the throttle linkage 1 turn for slightly better symmetry
I had 'hover throttle trim' inhibited in the system menu which seemed to stop the bottom end of the trim from working.
Still a little unsure why, but fixed all the same.
Chris