Pitch Stick Tension - Beginner Needs Advice

[Nigel Heather]

As a beginner trying to learn to fly a relatively small helicopter (Align 470) I have noticed that when covering, if I rotate the helicopter using the rudder I invariable lose or gain height.

 

I have just switched transmitters and it is apparently obvious what is happening on the new transmitter as the sticks are silky smooth.

 

I'm a thumber, I appreciate all the suggestions that pinch is better but I'm not going to change, I've been flying fixed for 10s of years and my brain is wired into the thumbs technique now.  I notice that when I apply rudder (I fly Mode 2) I can see the pitch position of the stick moving - finding it difficult/impossible to move the rudder independently.

 

I've taken the ratchet of the pitch axis but the tension is quite light.

 

I'm wondering whether it would be a good idea to increase the tension of the pitch and reduce the tension on the rudder.

 

Does that sound a good idea, or is the proper answer to keep practicing.

 

On my new transmitter, the gimbals can be rotated a little - wonder if it is worth playing with that?

[Richard Wills 2]

The tension is personal choice, I like mine to stay where I put it to some degree.  The most important thing is that it is totally smooth, and has no 'sticktion'  .  Spektrum sticks are awful for this, there is a perceptable jerk as it starts to move.  This can be solved by putting a strip of teflon sheet on the metal tension strip.

 

For the thumb v pinch, I pinch but a hybrid where you thumb the cyclic and pinch the collective sticks works as well.  The height changes when using rudder could be cross controlling, and practice makes perfect here.  But using the tail rotor affects collective and roll and will require adjustments on both to remain in the same spot, again practice practice practice

 

Edited April 3, 2023 by Richard Wills 2

[john stones 1 - Moderator]

Yep stiffen em up, gives a more noticable neutral, and as you've just started but noticed the issue, your brain/thumb will learn to manage throttle better.

[Nigel Heather]

5 minutes ago, Richard Wills 2 said:

The tension is personal choice, I like mine to stay where I put it to some degree.  The most important thing is that it is totally smooth, and has no 'sticktion'  .  Spektrum sticks are awful for this, there is a perceptible jerk as it starts to move.  This can be solved by putting a strip of teflon sheet on the metal tension strip.

 

For the thumb v pinch, I pinch but a hybrid where you thumb the cyclic and pinch the collective sticks works as well.

 

Yes I'm aware of the stiction issue, I have a Real Flight controller (effectively a Spektrum transmitter with different electronics) and have added Teflon to that.

 

My new radio is FrSky X20, which has CNC gimbals and they feel buttery smooth at the moment but that might change as I increase the tension - I'll keep an eye on that.

 

I have heard of the hybrid method but never tried - maybe give that a go on the simulator and see how I feel.

[Richard Wills 2]

I have found the gimbals on my X20 excellent so far, very smooth.  Don't go too heavy on the tension though, as you advance you will find that the collective stick  is hardly ever still, constant micro adjustments needed to be accurate and then being able to accurately control a free moving collective without cross controlling will be rewarded.

Edited April 3, 2023 by Richard Wills 2

[Nigel Heather]

1 hour ago, Richard Wills 2 said:

I have found the gimbals on my X20 excellent so far, very smooth.  Don't go too heavy on the tension though, as you advance you will find that the collective stick  is hardly ever still, constant micro adjustments needed to be accurate and then being able to accurately control a free moving collective without cross controlling will be rewarded.

Oddly, or maybe it is quite common, I can move the collective without cross-crontrolling the rudder but not vice versa.

 

The tension on the collective is pretty light at the moment, my fault, I just removed the ratchet and didn't think about the tension.  The rudder is sprung of course so needs for effort to start it moving- reckon that is what is causing me to cross-input, plus poor technique of course.

[Richard Wills 2]

5 minutes ago, Nigel Heather said:

Oddly, or maybe it is quite common, I can move the collective without cross-crontrolling the rudder but not vice versa.

 

The tension on the collective is pretty light at the moment, my fault, I just removed the ratchet and didn't think about the tension.  The rudder is sprung of course so needs for effort to start it moving- reckon that is what is causing me to cross-input, plus poor technique of course.

This is what a pinch grip enables you to do much more easily

[Outrunner]

When I fly fixed wing it's thumbs on top of sticks with helicopters I pinch with the aid of a neck strap to take the weight of the transmitter.

 

I notice that a lot of, if not most of our European friends use a transmitter tray too. Never tried a tray but all the extra kit and caboodle puts me off.

 

[Keith Billinge]

If you rotate in the direction of rotor travel you will gain height as you're effectively spinning the rotor quicker and vice versa spinning the heli using "rudder" away from the direction of rotor travel will effectively slow the rotor and you will lose height. Simples! This happens on the real thing too!

 

[Nigel Heather]

20 minutes ago, Keith Billinge said:

If you rotate in the direction of rotor travel you will gain height as you're effectively spinning the rotor quicker and vice versa spinning the heli using "rudder" away from the direction of rotor travel will effectively slow the rotor and you will lose height. Simples! This happens on the real thing too!

 

 

Yes I know what it is happening, I said as much in my first post so not sure what you are trying to say.

[Peter Christy]

It is quite simple, really. I'm assuming you have a "conventional" helicopter where the main rotors rotate clockwise as seen from above. If you increase the pitch on the tail rotor to yaw to the right, then the tail rotor will draw more power, reducing the amount available to the main rotor, and the helicopter will sink. If you turn left, the pitch - and hence the power drawn by the tail - will reduce, resulting in more power to the main rotor which will tend to rise.

 

This tendency is less noticeable in electric powered helicopters compared to i/c, but it is still there and is a fundamental feature of helicopter flight. It is also more noticeable in smaller models.

 

I wouldn't advise increasing the friction on the sticks too much. As long as the stick remains in place if you let go of it, that should be sufficient. If you find you are moving the pitch while applying tail, you simply have to learn not to! 😉 Its all part of the fun of heli flying - all the controls interact with each other!

 

It is also quite possible that you have the pitch curve set too steep for smooth hovering. If I fly with a computerised transmitter, I always have the hovering pitch set to a much more docile setting than that used for aerobatics, relatively flat across the mid range. By using a 5 point curve with steep first and last sections, whilst being fairly flat across the middle, you make the helicopter much less sensitive to vertical inputs while hovering, but still have enough total range for circuits and emergency auto-rotations if required.

[Cuban8]

Good advice from Peter. Despite what I say about teaching oneself, I taught myself to fly helis from scratch fifteen years ago - 450 and 500 size electrics. Eventually passed my heli  'A' and could fly a decent circuit and very basic aerobatics, was happy with that so didn't take it further.

No way could I ever be a pinch flyer after so many years of fixed wing thumbing. Tried it on the sim and found it totally alien - had enough to learn and relearn at the time so stuck with what I knew and was comfortable with - thought I did pretty well, even if I do say so myself😉

 

[Martin Harris - Moderator]

Maybe a bit unusual but on the fairly rare occasions I fly helicopters or multi rotors I pinch the sticks but I’m a thumbs flier for the vast majority of my flying. 
 

I fondly imagine that it helps switch my mindset to rotary flying…
 

 

[Nigel Heather]

On 03/04/2023 at 16:30, Peter Christy said:

It is quite simple, really. I'm assuming you have a "conventional" helicopter where the main rotors rotate clockwise as seen from above. If you increase the pitch on the tail rotor to yaw to the right, then the tail rotor will draw more power, reducing the amount available to the main rotor, and the helicopter will sink. If you turn left, the pitch - and hence the power drawn by the tail - will reduce, resulting in more power to the main rotor which will tend to rise.

 

This tendency is less noticeable in electric powered helicopters compared to i/c, but it is still there and is a fundamental feature of helicopter flight. It is also more noticeable in smaller models.

 

I wouldn't advise increasing the friction on the sticks too much. As long as the stick remains in place if you let go of it, that should be sufficient. If you find you are moving the pitch while applying tail, you simply have to learn not to! 😉 Its all part of the fun of heli flying - all the controls interact with each other!

 

It is also quite possible that you have the pitch curve set too steep for smooth hovering. If I fly with a computerised transmitter, I always have the hovering pitch set to a much more docile setting than that used for aerobatics, relatively flat across the mid range. By using a 5 point curve with steep first and last sections, whilst being fairly flat across the middle, you make the helicopter much less sensitive to vertical inputs while hovering, but still have enough total range for circuits and emergency auto-rotations if required.

 

Got you - but that is more nuanced than what is happening to me.  My issue is much more fundamental, on the left stick I find it very difficult to move rudder axis without changing the pitch axis.

 

Also in your example, isn’t the governor meant to keep the head speed constant.  So if the rudder draws power away from the main rotor, the head speed will drop and the governor will increase the throttle.

[Allan Bennett]

1 hour ago, Nigel Heather said:

 

Got you - but that is more nuanced than what is happening to me.  My issue is much more fundamental, on the left stick I find it very difficult to move rudder axis without changing the pitch axis.

 

Also in your example, isn’t the governor meant to keep the head speed constant.  So if the rudder draws power away from the main rotor, the head speed will drop and the governor will increase the throttle.

 

I think Peter Christy's post at 16:30 yesterday covers it:  A nice S-shape pitch curve will dampen down the pitch change at the normal hover stick position, and then you just have to practice so as to avoid too much up/down stick movement when you're doing left/right movement.

 

You're right about the governor usually maintaining the head rpm quite accurately irrespective of power needed for the tail -- at least, with electrics.  Maybe it was a bigger problem with IC engined helis, for throttle response could be slower than with electric motors.

[Peter Christy]

I did say that it is more of a problem with an i/c motor.  However, a governor can only react and not predict. Once it detects a slowing of the motor, it will try to increase the speed, but by then the speed has already dropped. Yes it will mitigate the decay in speed to a large extent - also helped by the fact that electric responds almost instantly to a demand for increased torque - certainly much quicker than i/c. But note the "almost"! It is still not instantaneous.

 

Having said all that, it still sounds to me like you have the pitch curve set too aggressive for smooth hovering. You want it to be responsive, but not too responsive - especially while learning. Once you have trained your hands NOT to adjust pitch with tail rotor, you can increase the pitch response if you wish.

 

At the end of the day, the helicopter is doing what you tell it to. If its not doing what you intend, you have to learn to not tell it - er, if you get my drift!

😉

[Martin McIntosh]

A radio set I used for many years had very heavy Orbit sticks which suited my style of flying. They were nowhere near as precise as later types and had quite a bit of play at the centre, but I could perform a slow roll by just leaning on the stick a bit during inverted (I fly mode 1). I briefly changed to Simprop but the sticks were incredibly light and I could never get used to them. I now fly JR with the springs as heavy as they will go (i have always been a thumbs flyer).