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Old Sep 23, 2012, 04:37 AM
Sopwith Camel's Cousin
Between my tx and crashed aircraft
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Originally Posted by iskess View Post
I'm using an Eagle A3 for basic gyro turbulence dampening on 3 axis, for FPV. It really helps, and the plane handles the bumps wonderfully.
However, I notice that it has taken out some of my Twinstar's inherent positive stability, and made it more neutrally stable. For example, it resists turbulence trying to lift a wing, but once it does manage to find itself in a bank, it also resists the dihedral effect of trying to level the wings. So the net effect is that instead of having the wings rocking back and forth in turbulence, it smoothly rolls off one way or the other if I stop working the ailerons to keep wings level. Has anyone else noticed this?
....
As far as I know, this is what gyro systems in general will do: resist any changes not commanded by the transmitter, whether it is due to wind, wing dihedral (change coming from the forces from the wing traveling the air, not the transmitter) or anhedral, etc. This I believe is the flip side of a gyro making it easier to hold a knife edge (even in a wing with dihedral): easier to hold a knife edge (wings staying quite non-level) means resisting the wings going back to level.

As far as I know, gyro systems are not recommended for beginner planes for this reason.
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Old Sep 23, 2012, 06:44 AM
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If you want wing leveling then buy a Eagletree Guardian and set it to run in 2D mode. The Guardian has 3 Axis gyros and accelerometers that help the wing leveling.
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Old Sep 23, 2012, 06:51 AM
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Melbourne, Australia
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Not disagreeing with this as I think it is how most people would understand gyro action but to be really pedantic:

Gyros respond to ANY disturbance - whether from external forces or commanded by you.

So if you send a roll command to the plane by deflecting the aileron stick, the gyro doesn't know this. What it does know is that the plane starts to roll and it will issue a countermanding instruction to the servos.

This is what is called the "fighting the gyro" effect I believe.

Clever software can overcome this but simple rate gyros will always exhibit this phenomenon.

Quote:
Originally Posted by flying-llama View Post
As far as I know, this is what gyro systems in general will do: resist any changes not commanded by the transmitter, whether it is due to wind, wing dihedral (change coming from the forces from the wing traveling the air, not the transmitter) or anhedral, etc. This I believe is the flip side of a gyro making it easier to hold a knife edge (even in a wing with dihedral): easier to hold a knife edge (wings staying quite non-level) means resisting the wings going back to level.

As far as I know, gyro systems are not recommended for beginner planes for this reason.
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Old Sep 23, 2012, 06:53 AM
Team Wack-a-Mole
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Maryland
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Originally Posted by flying-llama View Post
As far as I know, gyro systems are not recommended for beginner planes for this reason.
I would not agree. I've put it on high wing trainers for people and I have it on my hawksky.

My first gryo was on the ailerons of a Midwest Aerostar .40 trainer back in the early 1990s. It was a mechanical single rate gyro. It held in the wind like a rock.

One thing I've not tried is a 3ch with gyro. Dont' know the results or potential of that.
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Old Sep 23, 2012, 12:27 PM
Sopwith Camel's Cousin
Between my tx and crashed aircraft
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Originally Posted by Prof100 View Post
If you want wing leveling then buy a Eagletree Guardian and set it to run in 2D mode. The Guardian has 3 Axis gyros and accelerometers that help the wing leveling.
Yes, I forgot to mention this. Having and using accelerometers will keep a plane level.

But as far as I know, this can even have certain bad effects at times: for example, if a plane is stalling, instead of letting the plane drop the nose to get out of the stall, "letting go of the sticks" on accelerometers will often keep the plane level and stalled. But then again, sometimes one wants to keep a plane level and stalled: that is roughly what the 3D "elevator" move is.
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Old Sep 23, 2012, 12:28 PM
Sopwith Camel's Cousin
Between my tx and crashed aircraft
Joined Mar 2006
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Quote:
Originally Posted by jj604 View Post
Not disagreeing with this as I think it is how most people would understand gyro action but to be really pedantic:

Gyros respond to ANY disturbance - whether from external forces or commanded by you.

So if you send a roll command to the plane by deflecting the aileron stick, the gyro doesn't know this. What it does know is that the plane starts to roll and it will issue a countermanding instruction to the servos.

This is what is called the "fighting the gyro" effect I believe.

Clever software can overcome this but simple rate gyros will always exhibit this phenomenon.
Yes, I had in mind more than simple rate gyros, which as I remember from old beginner helicopters, will do what you say.
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Old Sep 23, 2012, 12:32 PM
Sopwith Camel's Cousin
Between my tx and crashed aircraft
Joined Mar 2006
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Originally Posted by Melnic View Post
I would not agree. I've put it on high wing trainers for people and I have it on my hawksky.

My first gryo was on the ailerons of a Midwest Aerostar .40 trainer back in the early 1990s. It was a mechanical single rate gyro. It held in the wind like a rock.

One thing I've not tried is a 3ch with gyro. Dont' know the results or potential of that.
Thanks, this reminds me: you can probably set the gyro gain so that it is high enough to fight some wind, but yet low enough that the dihedral, etc. effect will overcome the effects of the gyro (probably helps to have something like a high wing trainer that has a strong dihedral, etc. effect).
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Old Sep 23, 2012, 01:03 PM
Team Wack-a-Mole
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the Rate gain mode of the gyro will fight quick unwanted movements.
30% gain is enough to notice improvements. quick gusts affect a dihedral plane and makes it want to roll over. If you have ailerons on a gyro, then it will counteract that and make landing in a crosswind easier.

One point I was making the other day in a personal conversation is that the gyro will NOT negate all effects of the wind. It has the highest effect on dampening gusts or wind velocity changes. 10mph headwind or 10mph crosswind if it's absolutely steady (it never really is) would not have as much of difference with or without a gyro. But we all know wind speed changes is the real factor in sudden plane movements. Much of windspeed changes are when you are closer to the ground and you fly over or near ground contours or objects
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Old Sep 23, 2012, 01:25 PM
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United States, FL, North Fort Myers
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Quote:
Originally Posted by Melnic View Post
the Rate gain mode of the gyro will fight quick unwanted movements.
30% gain is enough to notice improvements. quick gusts affect a dihedral plane and makes it want to roll over. If you have ailerons on a gyro, then it will counteract that and make landing in a crosswind easier.

One point I was making the other day in a personal conversation is that the gyro will NOT negate all effects of the wind. It has the highest effect on dampening gusts or wind velocity changes. 10mph headwind or 10mph crosswind if it's absolutely steady (it never really is) would not have as much of difference with or without a gyro. But we all know wind speed changes is the real factor in sudden plane movements. Much of windspeed changes are when you are closer to the ground and you fly over or near ground contours or objects
Melnic, sir as you know I'm still in flight training but on my first day we flew (buddy boxed) this 63" Cessna 182 flew great. But I had checked the gyro action before this first flight and had the A3 rate only board set to 100% on all 3 and didn't know it.

I turned them all off the second flight and the plane needed lots of corrections on take off so my instructor told me to turn the rudder gyro back on, so I set it back to 100% He wanted to see how much difference it wound make in a 10MPH cross wind it tracked right down the yellow line. My instructor doesn't know much about gyros.

Will most planes fly ok with these gyros set at 100% ?

Thank you,

DJ - Kamikaze Ace Wears no helmet!
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Old Sep 23, 2012, 01:41 PM
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Originally Posted by Sculptor View Post
Melnic, sir as you know I'm still in flight training but on my first day we flew (buddy boxed) this 63" Cessna 182 flew great. But I had checked the gyro action before this first flight and had the A3 rate only board set to 100% on all 3 and didn't know it.

I turned them all off the second flight and the plane needed lots of corrections on take off so my instructor told me to turn the rudder gyro back on, so I set it back to 100% He wanted to see how much difference it wound make in a 10MPH cross wind it tracked right down the yellow line. My instructor doesn't know much about gyros.

Will most planes fly ok with these gyros set at 100% ?

Thank you,

DJ - Kamikaze Ace Wears no helmet!
I have to jump in. A new plane should be flown first with NO gyros to assure trims are correct. Then, bring on the gyros beginning with a 30% setting and ease your way up until you notice oscillations from too much gyro control then back down.

Bill
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Old Sep 23, 2012, 02:23 PM
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Quote:
Originally Posted by Prof100 View Post
I have to jump in. A new plane should be flown first with NO gyros to assure trims are correct. Then, bring on the gyros beginning with a 30% setting and ease your way up until you notice oscillations from too much gyro control then back down.

Bill
Bill, thank you sir. I had no intention of having all those on, it was unintentional. Except for the rudder they have been off ever sense.

BTW: I'm thru with the 'pattern' flying and the 'take off' part. (My take offs were sooo 'scale' Except the one were the front wheel came loose and I lifted just as it hooked right and hit the fence post at full speed. Plane exploded straight up and came down in 9 pieces. Landing training starts this week.

Thanks for the drawing.

DJ
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Old Sep 23, 2012, 02:49 PM
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Originally Posted by Sculptor View Post
Bill, thank you sir. I had no intention of having all those on, it was unintentional. Except for the rudder they have been off ever sense.

BTW: I'm thru with the 'pattern' flying and the 'take off' part. (My take offs were sooo 'scale' Except the one were the front wheel came loose and I lifted just as it hooked right and hit the fence post at full speed. Plane exploded straight up and came down in 9 pieces. Landing training starts this week.

Thanks for the drawing.

DJ
DJ,

I played with rate gyros on pitch and roll of an Aerocat (pusher prop flat jet) with full 100%. The wings flapped like a bird and the pitch was hilarious.

Bill
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Old Sep 23, 2012, 02:57 PM
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Deville, Louisiana
Joined Sep 2008
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Well I only put these gyros on the plane to keep it stable. Guess I just need to learn how to fly it without gyros for now. I do have other planes I could put 'em on. Also with the elevator gyro only I can have better landings. Just need to watch over the ailerons.

Russ
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Old Sep 23, 2012, 02:59 PM
It flies or it dies
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Deville, Louisiana
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Originally Posted by Prof100 View Post
DJ,

I played with rate gyros on pitch and roll of an Aerocat (pusher prop flat jet) with full 100%. The wings flapped like a bird and the pitch was hilarious.

Bill
Hey Prof. It's great to see you back on here. It's been awhile.

So what did you do to correct the problem?

Russ
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Old Sep 23, 2012, 03:04 PM
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Originally Posted by Russ The Flyer View Post
Hey Prof. It's great to see you back on here. It's been awhile.

So what did you do to correct the problem?

Russ
I have been reading but not posting. I have been playing with the Guardian.

To correct flapping the wings and pitching i dialed the two gyros back to 30%.
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