Pitch Curves

[T-ster]

What does everyone set up their pitch curves at? One magazine I've read set normal and idle up's at 0 degrees for mid stick, another sets normal at 4 degrees with idle up's at 0 degrees mid stick.

I currently have mine set up as -4,4,9 and am starting to think about idle up setups. My idle up is -9,0,9, but have not engaged it as of yet....


What is the advantages/disadvantages to each?

[Hotwings]

personally i have zero pitch at mid stick in all modes, normal, idle 1,2 and hold. this way the pitch curves are identical in all modes and when you switch modes you have no jump or change in pitch. i once flew Alan Szabo's Raptor 70 and he had hover in normal at midstick and when i went to idle up i almost drove it in the ground. I don't think he sets them up like that anymore.
The old school way was 4-5 deg at midstick in normal and 0 pitch in other modes.

Do it the way you feel best for you. Ron

[LJS]

Hi T-ster,

I like to keep things simple. I set to -12/+12 for all flight modes.

When I started out, I did the +4 at mid stick thing. However, as soon as I wanted to use Idle Up 1, I found the heli jumping up and down like a gnat in heat. Since then, I've set them all the same and have no issues when switching from one mode to the next. You just have to be careful not to pull the throttle/collective down in an emergency. That was never a problem for me.

Oh, on that same vane, once you start switching flight modes, you'll want to make sure all your trims are the same for all flight modes. That one caught me when I started switching flight modes.

Keep 'em flying.:YeaBaby:
LJS

[c_forthofer]

Only problem with not havng the same mid stick pitch (or for more clarity I should say the same pitch curve above mid stick position across all your curves) between your two curves is going to be the fact that when you switch between modes the heli is going to do wierd stuff (ie dive or climb) If your normal curve is +4 at mid stick (hovering I would assume) what is gong to happen when you go to idle up 1 and all of the sudden your pitch is 0 for the same stick position. Watch some of finless's setup video's he does a much better job of explaining it than I ever could.

Chris.

[p00rboi]

Most people now days run 0 degrees at mid stick for each flight mode. The advantage of setting it up this way is there will be no pitch change when switching between flight modes with the collective stick at the same position. With your current set up, if you were to switch into idle up from the hover your heli would drop. Many old school pilots would set up the hover at mid stick in normal mode. Most pilots today hover around 3/4 stick.

[T-ster]

Ok, I'm starting to buy into the 0 degrees at mid stick for all flight modes. Question though, I have a 5 point curve with my Futaba 8UAFS, what is your pitch at each of the 5 points for normal and idle up? Is it linear?

[LJS]

Hi T-ster,

I have a Spektrum and inhibit the 25% and 75% values. I go from 0% (-12) to 50% (0) to 100% (+12). But it's really just a straight line from 0 to 100. Pretty simple...

Keep 'em flying.:YeaBaby:
LJS

[T-ster]

How does this sound?

Normal : Pitch= -4, -2, 0, 5, 9
Idle Up: Pitch= -9, -5, 0, 5, 10

[SonicJeff]

If you set up for mid stick hover in normal and 0 degree pitch in stunt mode you have to be careful both when you switch into and out of stunt mode.

I never had too much trouble switching into stunt mode, the heli would drop a little bit. But when I landed in stunt mode and then switched to normal and the heli jumped up 4 feet off the ground, that got my attention. I changed so that all curves are the same from mid-stick up.

[TheBum]

How does this sound?

Normal : Pitch= -4, -2, 0, 5, 9
Idle Up: Pitch= -9, -5, 0, 5, 10

I didn't actually measure the final angles, but my radio is set up for 40-45-50-75-100, which probably works out about the same except that my collective is set up for +/- 11 degrees. Hopefully, you'll get to see me fly it the next time we go out to the field and not have the blasted engine cut out on me. This weekend looks a bit too windy, though, unless we try for a couple of hours in the morning or late afternoon on Sunday.

[mccrind]

Don't try any forward flight in normal mode then. With that limited negative set up you'll have a hard time transitioning back into a hover because transitional lift will cause you to float until the head speed decays, then a big drop.Much better to run full collective in all modes and just remember not to pull full negative in a panic situation( crashing ). Practice pulling throttle hold so that if you want to kill the power you can without pulling neg pitch and plowing the heli.

[aussiemick]

Normal mode -3, 0, +10
IU 1 -10, 0, +10
IU2 -12, 0, +12

IN normal mode it can be flown around very comfortably and I can bring it in to a quick stop without having to go below half stick (0' pitch).

Mick

[helibalou]

Good stuff guys, but how about throttle curves,
I will be using a Multigov governor, but from what I am reading the throttle curves still need to be setup.

In Normal mode I will use No Gov.
In Idle 1 Full Gov
In Idle 2 Ovsp Limiter


I am not sure what to set my throttle curves to.

[TheBum]

Don't try any forward flight in normal mode then. With that limited negative set up you'll have a hard time transitioning back into a hover because transitional lift will cause you to float until the head speed decays, then a big drop.
It depends on your throttle curve. I have a pretty steep curve between points L and 1 on my DX7: 0-30% when I'm using governor, 0-40% when the governor is off.

[Burt]

I have couple questions regarding pitch, on my setup for 0 degree at midstick one of the short likage rods on the top is a turn more then the other side, is this ok?

I thougth of setting mines as the other guy at normal with -3, 0, +10 on my Futaba 9cap thers a 5 point curve, what do you put in for the 2nd and 4th point?
I have as of now
40 -3
45
50 0
75
83 +10

On my rappy i ran 0, 25, 50, 75, 100 for all my idle ups

[TheBum]

Are you talking about the linkages to the blade grips? It's somewhat common for them to be different lengths to correct blade tracking.

[AXE3D]

OS .50 Hyper

Normal

Point Value Pitch Throttle
1 25 -2 12 (idle)
2 27 -.5 25
3 30 0 45
4 46 5 60
5 62 10 85

Idle Up

Point Value Pitch Throttle
1 0 -14 100 (max)
2 15 -7 85
3 30 0 55
4 50 7 85
5 70 14 100

The above curves have been tested through about 4 gallons so far. I have been gradually bumping down the zero pitch throttle to prevent over-speeds when leveling out from verticle dives. So far this thing doesn't overspeed with proper cyclic and collective management. The Hyper can't maintain headspeed above 13 degrees of pitch so watch out at 14, it bleeds slowly. Add in any amount of cyclic ontop of 14 degrees of pitch and the head will RAPIDLY slow. The 14 is there, but never really used. It saved me once. I hope it helps.

1 Futaba 6EX settings.

[Burt]

Heres another question, if I have a pitch range of +15 to -15 and ZERO in center stick, why is my numbers in pitch curve 18 for -10 and 84.5 for +10. Should they not be exact equal as 18 for -10 and 82 for +10???

[aussiemick]

Yes they should be.
Did you set the head up for even pitch with a pitch curve of 0, 50, 100?
+-15 deg pitch sounds like a absolute $h*tload, maybe you have your swash a little low on the head thus giving you an uneven pitch range. I was of the opinion that with the swash at the right height in the heli, +-14 deg was as much as could be dialled in. I have increased the pitch to +-13 deg in IU2 and notice a good bit of bogging if my collective usage is anything other than spot on.

Mick

[Burt]

This is with the UK swashplate and ready heli align tool underneath swash.

[Burt]

Gosh ive been at it for quite a while, downed 2 charges, here is my problem and I cannot resolve it as of yet.

Right Blade
Full negative 15 degrees
Center stick 0 degrees
Full Positive 15 degrees

Left Blade
Full Negative 14 degrees
Center Stick 0 degrees
Full Positive 15 degrees

Everything matches but one blade its extremely odd to me and frustrating, if not for this I would have broke in engine today. What misalignment is making this occur.

[TheBum]

It sounds like a CCPM interaction to me.

[Burt]

It is ccpm interaction, at full low stick my elevator is angled, as well as full high, but everything is perfectly 90 at center stick 0 pitch with swash leveling tool. If I put my elevator ATV 110/110 everything works out. Is this ok or is it mechanical, I re-measured everything and have been looking at my servos for ages, they are all 90.
I seemed to have found the exact problem on runryder http://runryder.com/helicopter/t408482p1/