Curves for Trex 800 and Wren 44 please.

[SimT]

I have eventually finished my Trex 800 Revolution Models conversion after a lay-up while I had a hand operation.

It is all finished and ready to set up the curves and fire it up. I have headloaders on to try it out.

Could you give me some starting points bearing in mind I am not a 3D flier and only really progressing on from circuits so no need for screaming head speeds and revving the nuts off the turbine please.
Thanks

Simon

[Kiba]

Unfortunately that's something you need to experiment with... each individual turbine is a little different, not to mention gear ratios between different helis, blade length, blade type, etc all play into the actual throttle curve and headspeed.

One thing I recommend initially is setting the heli at zero pitch or very slightly negative and then slowly increasing the throttle percentage until you hit your target headspeed (telemetry makes this easy, if not get a helper with a headspeed tach.) That will establish your mid stick / 0 pitch throttle point for your desired headspeed.

Depending on gear ratio, blades, and and target headspeed, I'm guessing you're going to end up somewhere around 40-45% throttle output at mid-stick for a headspeed around 1750rpm.

After the 0 pitch throttle position and headspeed is established create a parabolic throttle curve that's somewhat flat around the center (you won't need much additional throttle between say -3 / +3 degrees of pitch) and assuming you're running a decent amount of total pitch have the throttle curve end at 100% at full pitch. Then go fly it easy and see how it sounds and feels (again-- telemetry is a plus, if not a helper with a tach is needed.)

Depending on what TX you have you may be able to move the throttle curve points along the collective stick axis (left and right typically); I like to place two points that exactly line up with the stick position and pitch at hover so I can adjust those two throttle curve points to precisely control headspeed at a hover (both upright and inverted.)

After that, do some climb outs at varying collective inputs noting stick position to see how well the collective to throttle curve is doing for maintaining headspeed and tweak the throttle curve as necessary.

Once you get that dialed in, if you feel the headspeed bogs on certain cyclic-hungry moves that don't require much collective input (like funnels or continuous tumbles) you can then start adding and experimenting with cyclic to throttle mixes. Depending on how you fly you may or may not need cyclic to throttle mixes.