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F3C hovering curves

I3DM

rrProfessor

Israel

Hello guys.
i was just wondering which curves do you run in hovering mode for F3C competition flying, both throttle and collective ?

i had an idea, to define 1 idle up to hovering only, and run the throttle at about 30-50-70, with collective lets say 2-5-8 degrees, this way the hovering will be all over the stick and the heli would feel more sluggish to corrections in collective (not jumpy) - does this sound right ? what do you guys do ?
thanks.

www.liorzahavi.com

10-13-2004 Over year old.
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Secret Squirrel

Key Veteran

New Zealander living in Melbourne, Australia

I use normal mode for hovering only.

On my Sylphide which I use for F3C the curves are:
Pitch:
24,33,41,48,54,60,66,71,76,80,84,88,92

Throttle:
0,28,33,35,37,39,41,43,45,48,53,59,65

I hover at 1400 and aim for 1900 in aerobatics.

Si

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Simon Lockington

10-13-2004 Over year old.
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I3DM

rrProfessor

Israel

Hey Si, thanks.

how much do the pitch curve numbers translate to on the heli itself ? i see the throttle opens to 65%, which is similar to what i thought.
thanks again.

www.liorzahavi.com

10-13-2004 Over year old.
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Secret Squirrel

Key Veteran

New Zealander living in Melbourne, Australia

92% would equal about 9 or 9.5 degrees I would say

24% would be about -5.

I have a slider set up so that I can get more or less top and bottom pitch depending on if the day is windy or not. Sometimes you really have to pull the machine down in the hovering maneuvers on a windy day.

In autorotation I have a full linear curve with every bit of negative and positive pitch I can get.

Si

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Simon Lockington

10-13-2004 Over year old.
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GM1

Elite Veteran

Tallahassee, Florida US

Slightly different

My F3C models have -8 to +12 available in every condition. The 9Z has a top and bottom pitch limit in the pitch curve screen and I use that to limit the top end pitch and bottom end pitch according to my needs for that flight condition. The difference between using this function and % in the pitch curve is that I still have 100% of my pitch resolution left in every condition, going from 0% to 100%, so I can fine tune each one versus limiting the volume using % in the pitch curves where I might go from 30% to 80% and I would only be using 50% of the available resolution. In normal (hovering) condition I use a pitch volume control on a knob so I can steepen the collective curve on windy days and close it down on calm days and in other conditions I have top end pitch only on a slider so if I am making a little more or less power that day I can still get the motor to load (or unload) correctly. An example, in normal 100% collective is 10 degrees, in idle1 100% collective is 11 1/2 degrees, in idle 2 100% collective is 9 degrees, in hold 100% collective is 12 degrees, so each one can be a little different and I still can go all the way from 0% to 100% in every condition for my best possible resolution.
I adjust the top and bottom to get the "feel" I want when hovering. If the model is jumpy, I raise the bottom and lower the top limits, If it is sluggish, I raise the top and lower the bottom limits. With a little practice, you can get exactly what you want and it may not be the same as mine or anyone elses. I hovered Wayne Mann's model recently and it was VERY soft both cyclically and collectively compared to mine but he hovers it great. If I tried to set mine up that soft, I would be behind it all the time so I run a more aggressive setup. Now I have never hovered Curtis' model, due to the unique single stick radio configuration and the fact he never offered to let me try it , but by observation, his model is even more aggressive than mine. So set the feel to suit yourself and you may find that as your skills improve, you can turn things down and make the model really smooth and silky.
As an aside, I use 5 idle ups to allow for special conditions for unusual maneuvers like Idle 2 is only for rolls. It has 100% aileron, 40 % elevator and 30% rudder to keep me from "leaning" on something else accidentally and screwing the whole maneuver up. In idle 4, I do the pushover, cobra roll, and pullover. It has a massive amount of elevator, moderate aileron, and just enough rudder to do a 4 second pirouette, all with huge amounts of expo so I can snap into the hover but have a soft stick to hold the hover while pirouetting. The whole thing is a compromise to get max performance with minimum work for the pilot.
Gordie

On a dog sled team, if you're not the lead dog, the view never changes.

10-13-2004 Over year old.
Henrik Engert

Key Veteran

Cedar Park, TX

The difference between using this function and % in the pitch curve is that I still have 100% of my pitch resolution left in every condition, going from 0% to 100%, so I can fine tune each one versus limiting the volume using % in the pitch curves where I might go from 30% to 80% and I would only be using 50% of the available resolution.
I don't understand what the diff is between limiting the hi and low from just adjusting the points on the curve....is this not the same?

10-09-2005 Over year old.
vols77

Senior Heliman

Hills of Tennessee

I'm with Hinkle, I would like to know more about the pitch limit function on the 9Z.

I have been using AFRs in each mode to limit the pitch and then the pitch curves in each mode can be close to 0-100%.


Rick

10-10-2005 Over year old.
mrNoodles

rrProfessor

Borlänge, Sweden

Im with Rick and Hinke

Hi/low sounds like exactly the same as the low/high point on the pitchcurve to me?
Would be nice to have it explained.

Either way you get 100% stickmovement (highest resolution).

Thanks!

10-10-2005 Over year old.
HOMEPAGE  
GM1

Elite Veteran

Tallahassee, Florida US

Curves

OK, this is a little tough to explain but it is true.
The 9Z using AFRs and ATVs at 100% give you a certain amount of available pitch, lets say 25 degrees total. Now our motor won't pull that much but it makes it easy to calculate. In the pitch curve screen we leave the high and low pitch trimmers at 100%. We set point 1 at 20 % and point 13 at 80%. Now our points 2 through 12 are compressed into 60 steps (80-20) Now we have 60% of 25 degrees so each % of pitch curve is 1/60 of 15 degrees or 1/4 of a degree. (.25 degrees per %) If I use the high and low trimmers set at 20% and 80%. I still have 60% of the available pitch but point 1 is 0% and point 13 is 100% so I have 100 steps between them for points 2 through 12. so each % is 1/100 of of 15 degrees (60% of 25 degrees, yes, I know that's not exactly correct because of servo nonlinearity but it's close) which is 3/20 of a degree (.15 degrees per %). So I can have more available steps between points on my pitch curve by using the high low trimmers and can more easily fine tune my curves. Now all this is within the limits of servo resolution which is 1024 steps for 280% total travel (140% each way) so it seems to work out better using 100% of the pitch curve and limiting the pitch with the trimmers than limiting pitch using the curves.
I'm at work and don't have a 9Z in front of me so I cannot actually remember if the trimmer uses 20 to 80 or -100 to +100 but I can end up with the same limits either way. Does this make sense to you?
Gordie

On a dog sled team, if you're not the lead dog, the view never changes.

10-10-2005 Over year old.
mrNoodles

rrProfessor

Borlänge, Sweden

At first it didnt, but now it does, you get less degrees / % of the stick movement.
Thanks Gordie

10-10-2005 Over year old.
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Henrik Engert

Key Veteran

Cedar Park, TX

ok. I have to go back and use the Hi/low on my curves now.

Thanks.

10-10-2005 Over year old.
mrNoodles

rrProfessor

Borlänge, Sweden

Hehe Im sure it will improve your flyingskills

10-10-2005 Over year old.
HOMEPAGE  
Henrik Engert

Key Veteran

Cedar Park, TX

Maybe

Actually, I feel much more at home with the 9Z than my 8U radio But, I guess now I have to perform since I have this expensive radio....oops.

10-10-2005 Over year old.
vols77

Senior Heliman

Hills of Tennessee

Thanks Gordie,

I'll have to start using the high/low pitch function.

Rick

10-10-2005 Over year old.
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F3C hovering curves

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