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Old 01-27-2012, 11:49 PM   #1
photocycler
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Default Keeping Slow Control

I seem to have a hard time keeping slow flight, any tips appreciated. It seems I give a little elevator and ease into it and it just starts picking up speed

Last edited by photocycler; 01-28-2012 at 12:10 PM..
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Old 01-28-2012, 12:10 AM   #2
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What heli?
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Old 01-28-2012, 12:10 PM   #3
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What heli?
mainly in the sim right now
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Old 01-28-2012, 02:14 PM   #4
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I don't have time for a detailed reply.

But here's something anyway.

When you're in a stable hover and pitch (tilt) forward, the heli will start to move forward but lose altitude. In order to maintain altitude you have to add collective pitch. The speed that you attain will depend primarily upon how much forward pitch (tilt) you have. The less forward pitch, the slower your speed will be.

Sorry, but I have to get ready for work. Hope this helps out a little and I'm sure others will add to it.
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Old 01-29-2012, 04:13 AM   #5
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Bob O is right about loss of lift, here are a few more thoughts.

Bear in mind that when tilting the heli forwards, the heli will accelerate. Acceleration is any change of velocity. It will pick up speed until the increasing drag balances out the forward thrust. Then the heli will stop accelerating and keep the velocity constant. All this is ideally but the principle holds true. Add non constant wind, turbulence etc etc and the retarding forces will affect how much forward thrust you need to keep the velocity constant. More tilt, greater thrust, greater velocity before drag brings the acceleration to zero.

Try this: In a hover, give the cyclic a tiny nudge forward. The heli will accelerate. Almost immediately, give the cyclic a tiny nudge backwards to level the heli. If the heli is level, you'll have no forward thrust to accelerate the heli, only drag (since it's moving) to slow it down. To keep the velocity constant is a balancing act. You need to constantly balance horizontal thrust against drag and moving air.
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Old 01-29-2012, 06:08 PM   #6
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I have the same issue...hard to have a slow forward flight (under 10 mph).
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Old 02-02-2012, 10:37 PM   #7
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Quote:
Originally Posted by LN400 View Post
Bob O is right about loss of lift, here are a few more thoughts.

Bear in mind that when tilting the heli forwards, the heli will accelerate. Acceleration is any change of velocity. It will pick up speed until the increasing drag balances out the forward thrust. Then the heli will stop accelerating and keep the velocity constant. All this is ideally but the principle holds true. Add non constant wind, turbulence etc etc and the retarding forces will affect how much forward thrust you need to keep the velocity constant. More tilt, greater thrust, greater velocity before drag brings the acceleration to zero.

Try this: In a hover, give the cyclic a tiny nudge forward. The heli will accelerate. Almost immediately, give the cyclic a tiny nudge backwards to level the heli. If the heli is level, you'll have no forward thrust to accelerate the heli, only drag (since it's moving) to slow it down. To keep the velocity constant is a balancing act. You need to constantly balance horizontal thrust against drag and moving air.

does this mean that you are constantly using backwards and forwards movements when doing slow forward flight?

im having the same problem as the OP. slight nudge forward the heli moves forward, but i try to slow it down with a nudge back, but the heli just stops instead of slowing down, but still moving forward.

i hope im explaining this right.

edit: flying the mcpx.
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Old 02-03-2012, 09:28 AM   #8
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does this mean that you are constantly using backwards and forwards movements when doing slow forward flight?
That will depend entirely on how the heli accelerates and whether or not you want that acceleration. To keep a constant speed, you need to keep the acceleration to zero. So, if the wind tilts the heli, you'll need to correct that. If the wind pushes the heli accelerating it, you'll need to correct for that. Wind slowing the heli down, need to correct that too. Sideways, same thing.

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im having the same problem as the OP. slight nudge forward the heli moves forward, but i try to slow it down with a nudge back, but the heli just stops instead of slowing down, but still moving forward.
Do I understand you correctly, the heli doesn't slow down but either flies forward or stops completely? No change of velocity can happen at zero time, so from moving forward to coming to a stop, it MUST accelerate (remember, acceleration can be both positive and negative). If I understand you correctly, then it accelerates but the acceleration is so high it takes _near_ zero time to change speed from slow forward to stop.

What I'd think happens is that the rearwards tilt is so great (relatively speaking!) that the velocity change happens so fast you don't have time to bring the tilt back to "zero acceleration". Expo can help you with that by allowing lower tilt rate at minimum stick input.
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Old 02-03-2012, 03:32 PM   #9
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That will depend entirely on how the heli accelerates and whether or not you want that acceleration. To keep a constant speed, you need to keep the acceleration to zero. So, if the wind tilts the heli, you'll need to correct that. If the wind pushes the heli accelerating it, you'll need to correct for that. Wind slowing the heli down, need to correct that too. Sideways, same thing.



Do I understand you correctly, the heli doesn't slow down but either flies forward or stops completely? No change of velocity can happen at zero time, so from moving forward to coming to a stop, it MUST accelerate (remember, acceleration can be both positive and negative). If I understand you correctly, then it accelerates but the acceleration is so high it takes _near_ zero time to change speed from slow forward to stop.

What I'd think happens is that the rearwards tilt is so great (relatively speaking!) that the velocity change happens so fast you don't have time to bring the tilt back to "zero acceleration". Expo can help you with that by allowing lower tilt rate at minimum stick input.

sorry about that. i dont think i described it properly. the language barrier makes it hard for me to describe in perfect English.

heres what i mean. i nudge just a little forward (i want to practice going slow speed), but the heli starts to pick up too much speed.

i want to slow it down by a little nudge back, but instead of the heli slowing down, it stops, or goes backwards.

i do not want it to stop, or go backwards. i just want to slow it down, but keep moving forward.
i hope this makes sense.
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Old 02-04-2012, 03:18 AM   #10
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Ok, I think I get it now : )

2 things I'll suggest:

The mcpx is fairly responsive to both cyclic inputs and tilt changes meaning less input is needed to give the tilt needed and tilt will have a greater effect on acceleration than if it was a say, 450.
Have you tried varying EXPO and/or D/R? EXPO to allow a lower roll rate around centre stick, D/R to give you a lower roll rate at all stick positions.

Are your stick inputs really really really tiny? Are they at the "just think about pushing the cyclic and the heli moves" level? Keep working at making those inputs even smaller than they are.

I hope I understand you right and that this helps. Good luck!
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Old 02-05-2012, 09:56 PM   #11
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for some reason I just cannot get my inputs small enough..I can do fast circuits and stuff but when it comes to slow control in a small area I just cant keep the heli going slow, mainly when I am coming back towards me nose in it starts to speed up
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Old 02-05-2012, 10:36 PM   #12
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A good excercise some told me to try was to walk around the gym with the heli at the same relative spot in from of me. It helped me a lot as I got to see the results of my inputs very clearly and I was able to keep it at a walking speed just in front of me.

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Old 02-09-2012, 09:33 AM   #13
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For me... and you may have tried this... is I was "Holding" small inputs instead of bumping the stick and quickly returning it to center position. If that wasn't enough, I'd bump it again and go straight back to center position.

Just an idea.
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Old 02-09-2012, 11:50 PM   #14
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Not sure what it is, once the heli faces me nose in I just can't slow it down. I can control it all other ways

Must be a mental block,at this point
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Old 02-11-2012, 01:42 PM   #15
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For me... and you may have tried this... is I was "Holding" small inputs instead of bumping the stick and quickly returning it to center position. If that wasn't enough, I'd bump it again and go straight back to center position.

Just an idea.

so instead of holding the direction, just bump it instead?
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Old 02-12-2012, 01:57 AM   #16
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so instead of holding the direction, just bump it instead?
Yes. CP helis differ from FP coaxials here. A coaxial will level itself as soon as you let go of the cyclic. A CP will not. It will keep tilting for as long as you push the cyclic and equally important, as soon as you re-centre the cyclic, the heli will keep its attitude (more or less). So: Tiny inputs - re-centre - repeat.
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Old 02-12-2012, 06:13 PM   #17
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Quote:
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Yes. CP helis differ from FP coaxials here. A coaxial will level itself as soon as you let go of the cyclic. A CP will not. It will keep tilting for as long as you push the cyclic and equally important, as soon as you re-centre the cyclic, the heli will keep its attitude (more or less). So: Tiny inputs - re-centre - repeat.

thank you. im not used to little inputs. will definitely try it.
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Old 02-13-2012, 09:18 PM   #18
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On the MCPX try a dual rate of 40%, no expo.
Works good for precise flying and hovering.
I have been using that to practice inverted hovering.
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Old 02-20-2012, 09:47 PM   #19
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I have about 40% expo and DR of 70% on aileron and elevator

I have been trying to do slow circles in my garage which has about a 12x12 foot area open and have been trying in IU as I was thinking it would be better for stability

I can hover all directions but my nose in isn't as precise as the others
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Old 02-21-2012, 05:25 PM   #20
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Quote:
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mainly in the sim right now
Yup...that's one of the annoying things about the sim.

Kinda like driving on frictionless ice.

The real thing is a lot easier to control at low speed, but low speed is still difficult to master.

I practice slow flying a lot, and I believe it's an important skill to learn.
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