PIRO'S!!!

[Superbike1]

When I do Piro's, My heli takes off in one direction or another, Is it suppossed to do that? I can almost hands off hover it but it will still drift a little. When I piro, it won't drift, it will take off and I have to be quick on the sticks to catch it. Is there something off? It flies great,very little vibrations just thought that the as3x would make it more stable than it is!

[65L88]

The AS3X gyro in your Nano doesn't have piro compensation, so you need to add aileron and/or elevator input to compensate during piros, depending on how your particular heli is set up. The Nano, mCPX, and 130X are all the same in this respect. It helps to have your center of gravity as close to the main shaft as possible, but this becomes increasingly more difficult to achieve as the helis get smaller.

[ArchmageAU]

Originally Posted by Superbike1

When I do Piro's, My heli takes off in one direction or another, Is it supposed to do that? I can almost hands off hover it but it will still drift a little. When I piro, it won't drift, it will take off and I have to be quick on the sticks to catch it. Is there something off? It flies great,very little vibrations just thought that the as3x would make it more stable than it is!

As the tail rotor is not on the same plane as the main rotor disc, a nano hovers in still air on a lean (left high if I remember correctly). As you turn the tail, the lean of the disk will generate lateral acceleration. This is normal. The AS3X just tries to ensure the stable lean is maintained, it does not compensate for lateral movement.

If the nano is perfectly stable and tail in, in theory, a CCW piro should move forward and right, a CW piro should move backward and left.

Also in theory, you should be able to do small forward CW circles from a stable hover without touching the collective (just by using the to turn CW rudder).

[Superbike1]

Originally Posted by ArchmageAU

As the tail rotor is not on the same plane as the main rotor disc, a nano hovers in still air on a lean (left high if I remember correctly). As you turn the tail, the lean of the disk will generate lateral acceleration. This is normal. The AS3X just tries to ensure the stable lean is maintained, it does not compensate for lateral movement.

If the nano is perfectly stable and tail in, in theory, a CCW piro should move forward and right, a CW piro should move backward and left.

Also in theory, you should be able to do small forward CW circles from a stable hover without touching the collective (just by using the to turn CW rudder).

That's exactly what it will do. Thanks. Just checking to see if mine was right or if it had something wrong with the as3x.

[RichKnapp]

Originally Posted by 65L88

The AS3X gyro in your Nano doesn't have piro compensation. It helps to have your center of gravity as close to the main shaft as possible.

I love to do piro's and when I started trying with the Nano I found this to be the biggest problem. I went threw and set up my CG. Made a world of diffrence. I can now get a couple rotations in before it starts to move off center and I have to stop and save it.

Personally I think if you want to do Piro's, spend the time to get spot on and consistent (with battery placement) CG and save some $ on replacement parts.

[65L88]

Originally Posted by ArchmageAU

As the tail rotor is not on the same plane as the main rotor disc, a nano hovers in still air on a lean (left high if I remember correctly). As you turn the tail, the lean of the disk will generate lateral acceleration. This is normal. The AS3X just tries to ensure the stable lean is maintained, it does not compensate for lateral movement.

If the nano is perfectly stable and tail in, in theory, a CCW piro should move forward and right, a CW piro should move backward and left.

Also in theory, you should be able to do small forward CW circles from a stable hover without touching the collective (just by using the to turn CW rudder).

Actually, the reason the heli leans right is something called translating tendency, which is the tendency for the tail rotor to push to entire heli to the left (with clockwise rotating main blades). As a result, the heli has to be trimmed with right aileron to keep it in a stable hover, therefore the right lean. If you look at a full size heli in hover, you'll notice that all of them with tail rotors lean in the direction of tail rotor thrust. It really makes no substantial difference where the tail rotor is in relation to the main rotor disc, they all will do this to one degree or another.

Although you are correct about the rotor disk angle being a factor in the heli wandering during piros, there are other dynamics affecting them also, such as center of gravity (both horizontal and vertical) and numerous others.

[ArchmageAU]

Heli's are just unstable craft flown by unstable people

Any stability is just a transitory illusion.

My bad in my explanation. I assumed CG was correct and that the tails translating tendancy was compensated for by rotor lean and gyro compensation while hovering out of ground effect in still air. Also didn't mention gyroscopic precession

[65L88]

Originally Posted by ArchmageAU

Heli's are just unstable craft flown by unstable people

Any stability is just a transitory illusion.

My bad in my explanation. I assumed CG was correct and that the tails translating tendancy was compensated for by rotor lean and gyro compensation while hovering out of ground effect in still air. Also didn't mention gyroscopic precession

There you go!! and I'll happily include myself in the mix!!