Hi,
I was setting up the IdleUp curve today and was wondering this. In Normal mode, my heli overs at mid stick. In Idleup mode it hovers at 3/4 stick. Now when I am going to flip the switch from Normal to IdleUp, the Heli will kind of start falling unless i give immediate stick input. Opposite will happen when i go into normal mode from IdleUp.

Solution might be that in Normal mode, I setup the curves so the hovering is at 3/4 stick pos ? That would make the transition much smoother.

Is that what I should be doing ? ie Hover point in normal mode at 3/4 stick pos ?

This is why I have been saying from the beginning that you should switch to a single pitch curve for all modes, including hold, after you are comfortable with hovering of helis.

Setting a -3 to 10 curve for normal mode while learning to hover initially (on your first ever heli flying training) is a good idea, as it is smoother to deal with.  But as soon as you are comfortable with basic heli flying (ie, before you start going into idle-up), switch to a single curve for everything (-11 to 11 or -12 to 12, whatever you are comfortable with and whatever the heli can support).

Check your pitch curve, is the mid point in the normal, idle1 & idle 2 the same? Probably you got some positive deg in normal on the mid stick and you got zero deg on idle ups.
Basically if you keep your mid stick configuration to 0 degrees on all three flight modes this can be avoided.  My collective setup up is like this:
Normal : -4  :  0  :  +11
Idle 1  :  -6  :  0  :  +11
Idle 2  :  -11 :  0  :  +11
I usually only hover and move around in normal, in idle1 i restict to only some basic aerobatics like loops, rolls, 540s where i do not require much of negative and 3d flying on idle 2.
If you're using a governor then the head speed is 1650 in normal, 1800 and 1950 in idle 1 & 2 respectively.  If you dont have a governor, then i would keep the throttle curves like this:
Normal :  0  :  40  :  100
Idle 1  :   100  :  55  :  100
Idle 2  :   100  :  65  :  100
Also for the above setup, please ensure that your throttle servo is linear (atv 100) if you observe there is a small notch on the throttle arm which shows the marking of carb close, mid point and open, you can use this as a guide. 
Hope this helps.

Regards,
Adarsh

What Adarsh is suggest is another way of skinning the cat.  You can go either way, it is a matter of personal preference.  Having a single curve ensures that the pitch response is same even in the negative range, and that matters in the case of "hold" (for autorotation).  Adarsh did not specify what pitch range he uses for hold, but it is important that you are comfortable and well acquainted with the pitch range you use for autorotations.

Having a single curve ensures that your pitch response is the same in all modes and orientations.

hi guys.
my 2 penny worht.
a midpoint throttle setting the same in all modes would be a realy smooth progression..... 40 is perhaps a little low for normal... mine was always 70+ at midstick .
regards
don

That is one key difference between electric and nitro models.  Assuming you have the opening of the carb happen progressively over the movement of the throttle stick through its entire movement range (with 100% ATV on both ends, like Adarsh described above), you will typically hit the sweetspot for hovering rpm between 40 and 50 on nitro models.  The same thing for electrics is usually between 55 and 70.

Let me try to understand.

From What Anwar is saying, I keep the Pitch curve the same. -10 to +10 in ALL modes.
But I do not think that answered my question. In all modes should the hovering be at 3/4 stick position ?
Lets look at the hovering scenario and throttle curves in different modes :
Normal Mode
So at 3/4 stick pitch would around 5 degrees. Perfect for hovering.
Now what would the throttle be ( approx ) here, in Normal mode ? Having a linear curve would cause it to be around 75. Which would be too high . So the curve needs to be something like 0-20-100 ? That would cause the throttle pos. at 3/4 stick position to be around 60. And also keep the throttle down for the negative pitch part of the stick movement.

Idle Up 1
If we keep the throttle curve at 80-55-100, This would cause the 3/4 stick post to be at around 75 throttle . Too high for hte same pitch isnt it ? and the heli would kind of jump up when we go from normal to IdleUp 1 ?

Idle Up 2
Similar to above, but even higher headspeed. Not sure how it would hover at 3/4 stick...

Now Adarsh is perhaps saying something similar. His pitch curves are same for the 1/2 to full stick . The only difference is in the negative part.

I guess i will try this out today to see. BTW I still have wooden blades on , so I will not be going in for high headspeeds or aerobatics, but i do want to practise flipping the mode switch.. ie between normal and Idle Up 1 modes...

Obviously, the throttle curve will be different between -2,10 and -10,10 pitch settings for normal mode. So you have to adjust it by trial and error, to get it to your liking.  And it is true for other modes also, although not as pronounced. A governor really helps preventing you from going overboard on throttle, especially in idle-up.

The point is that pitch is mostly what causes the heli to jump or sink, as compared to throttle.  So keeping pitch the same when you flip between modes should pretty much get rid of that problem. 

Thanks. That helps. Will post a report in the evening.
BTW what are the limits of Wooden Blades ? I still havent got the CF ones, so using the stock TT Woodies.
Can i attempt stall turns, loops with them ?
Flips ?
Manual indicates no more than 1700 RPM with them.

Thanks !

which heli are you flying?...

Raptor 50 Titan

the reason why i asked was certain helis require certain headspeed for good control... never owned a raptor so cannot comment much...
myself i have the following for all my helis
normal
-2 inh 0 inh +12 (earlier i used to have -2 0 0 5 and +12). got rid of the 0 an the 5 at the 1/4 and 3/4 stick respectively just to get  smooth curve)
idl2 1 (which i dont usually use)
low stick - 8, mid stick 0 and high stick +12
idle 2 (i usually fly in this mode - except for take off on normal so that the esc get initialised)
low stick - 12, mid stick 0 and high stick +12
above half stick the curve is exact for all three modes and when you swith from normal to stunt modes the heli does not move except the rmp increases.. for hold i use the idle 2 curve...

Guys,
I did around 6 flights over the weekend, and had many observations/questions. Here is what I did.
- Treated myself (and the heli) to a TT Zero Alpha governor ( figured out i was going to need one, since i do not have anyone experienced besides me to help me during the setup ) .
- Setup the following curves :
Pitch
Normal: -5  0  +10
Idle Up1 -8  0 +10
Hold  -8  0 +10

Throttle
Normal: 0 - 50 - 100 Gov - UNLOCK
IdleUp 80 - 50 - 100 Gov - LOCK @ 1300 RPM

I know you will say that 1300 is too less. However I felt that even this was too much compared to what i was flying with earlier ! The heli felt much more agile, plus the blades were sounding very fast. I didnt dare increase the RPM further with my woodies on.

Good thing was that the flip between normal and idleup didnt cause any jumps, but looks like i need some practise on flying in IdleUp, since the throttle stick gets so sensitive.

Ok, now though my flights went all OK, i had many questions cropping up in front of me :
- Engine HSN/LSN still not tuned. Not sure how to tune the HSN, since I do not really get the engine to run at max rpm at eny time.
- If 1300 RPM sounds so fast, then 1700 would be even faster. Are the RPMs OK ? Looks like i was flying the heli earlier with the minimum RPM..

So i will open a new thread on heli engine tuning, and what i propose to do next.
BTW i did some auto rotations too, with the hold switch. It does take some courage in flipping that switch but then i was kinda doing baby autos from 5 feet. Will open a new thread on this as well.

Thanks everyone !

Quote from: gauravag on April 17, 2010, 11:35:17 AM
BTW what are the limits of Wooden Blades ? I still havent got the CF ones, so using the stock TT Woodies.
Can i attempt stall turns, loops with them ?
Flips ?
Manual indicates no more than 1700 RPM with them.

As long as you keep the rpm below the limits for the blade, you should be fine doing loops, rolls and stall turns.  Note that even for wooden blades, there are various brands which come with different limits.

When performed with enough forward speed, these maneuvers do not put undue load on the blades (as compared to doing them stationary or in-place).