It flies

[Bobs]

Well, I finished building last Wednesday and flew it that afternoon. After lift off the only trim that was needed was one click for right aileron. I've flown a couple times since, only about five/ten minutes each time though due to very windy conditions. Anyway, I do have a question about my throttle curve in stunt mode. Normal mode is working out fine, both pitch and throttle curve, but my question is this: for a pitch curve in stunt mode of -10 0 10 my throttle curve is set at 100% on the top and bottom, with 42% in the middle. If I use my radio to fill in the other numbers (9303 transmitter) they seem rather high for a gasser of 100 80 61 42 61 80 100. Does this sound right or should I reduce the 61 and 80% numbers? My pitch numbers for -10 0 10 are 3 20 37 54 69 85 100 and I'm lifting off at +3 which is 66%. I'm not using stunt mode yet but just wanted to get the numbers close before trying it. Eventually, I'm probably going to use a Stator Gator and Revlock, but I'd like to figure out my throttle curve first. Any help is greatly appreciated.

[Bobs]

I guess everyone uses a governor. Thanks anyway.

[MarkWebber]

I don't think it's really necessary. After Chris redid my curves, I can do agressive climbouts with the camera and it doesn't bog much. I understand that on the gassers they can cause more problems than they solve. Just what I've been told by an informed flier. :D

[Bobs]

Unfortunately, we don't all have the luxury of Chris setting up our helicopters for us. And from all I've read and heard, governors are highly recommended on gassers. I merely wanted to know if my throttle curve numbers were correct or not, for a starting point, because they seemed high for a gasser.

[cbergen]

Set your middle point to the same number as in normal mode. IOW, if your hover point in normal mode is 41, then set the mid point in Idle up 1 to 41 as well.

You can reduce the 61 and 80 numbers. I would bring the 61 down to 53, and the 80 down to 70. This will at least get you close.

Now go try some high power climbouts and listen to what the engine and headspeed does. If it overspeeds, then reduce the numbers some more. If it slows down, increase the numbers until the headspeed remains pretty close to the same.

Now you will hear different tones to the engine when you do this. Don't mistake this for a "bog". What's happening is your loading the engine more, putting more gas into it, it's bearing down, grunting, and giving you the power your asking of it!!

Starting at a high hover, put the heli in a quick descent to listen for overspeeding. If it does, then reduce the numbers (61 and 80) on the low side. This is also done in idle up.

You may ask, don't I want a higher headspeed for idle up to do aerobatics? Certainly!

Now that you have a curve that's relatively close to maintaining a given headspeed, you can bump up the points evenly across the board to raise your headspeed to whatever you desire. And you didn't even get out of your "comfort zone" to do it!! You start at a relatively calm headspeed, something that you're already used to, and work your way into an idle up curve.

You will also want to verify that your PITCH curves are identical in all flight modes as well. This will ensure that the same throttle curve numbers will give the same headspeeds, and prevent the "jump" when switching between flight modes.

Obviously this takes some tweaking, but I can usually get one setup within 2 or 3 tanks of fuel.

[Bobs]

Thanks, Chris. I do have one question, though. You mentioned that my pitch curves should be identical in all flight modes. Do you actually mean that in normal mode I should set my pitch up to be -10 0 10 or just the middle number (0) and top number (10)? I understand what you mean by it "jumping" when going from normal mode to idle up 1 (stunt mode) but I always thought that was just the way it was. Right now I have my pitch curve in normal mode set to -4 2 10. If I change the (2) to (0) then, obviously, the pitch curves would be identical in both flight modes from mid stick on up.