from hover to full throttle
 

I'm learning as I go about my heli and radio. Slow education is better than a crash course! lol
here's my question. When I go from low hover to full throttle my heli rotates about 45 degrees before gyro (gy240) "locks" tail in position. Is this normal?

RE: from hover to full throttle
 

Make sure you have REVO mixing inhibited in your transmitter. The easy way to tell is run the throttle stick up and back on the ground with the engine off. If the tail blades move as you move the stick, thats your problem. Also make sure you dont use any trim or sub trim with the rudder channel, if you do zero it out and set the linkage up to hover w/o trim so that the servo arm is 90 degrees to the pushrod. You can check this by flying with HH mode off, which on the 240 i believe is a switch on the top of the gyro.

Once you get that set and make sure any mixing is off, that gyro locks on very well.

RE: from hover to full throttle
 

Will try it. Thanks

RE: from hover to full throttle
 

make sure the gain is high enogh to, that can make the heli spin as you describe to.

RE: from hover to full throttle
 

It's probably the gain... if you have any revo mixing in HH mode, you're heli will spin, not just rotate 45 degrees and stop. In HH mode, the gyro sees the revo mix as a yaw command from you, so you'd actually have to give a corresponding rudder input to cancel the revo mix and keep it from rotating.

I've already been there and done that. ;) I set up a heli assuming the TX had no revo mix in the heli program by default... turns out it had 20% by default... in HH mode the heli would want to spin, in rate mode it was fine... I finally decided to go into the revo mix menu and check it... doh!

RE: from hover to full throttle
 

Well if you punch it to climb then come back to hover power, with revo enabled it will give the behavior indicated. So will low gain, among other things. Its always nice to check, cuz some radios like the 9C come with revo mix enabled by default (like the software was written when Michael Jackson was popular)

RE: from hover to full throttle
 

Thanks for the input. I won't be able to do anything for a couple weeks. I work on the road. Heli stays home. Keep ther in coming though. Thanks for all the help.

RE: from hover to full throttle
 

Nope, no more answers till you try what we already told you. :D

RE: from hover to full throttle
 

Did you trim the heli in normal mode before setting it to HH?

RE: from hover to full throttle
 

heli was set up several months ago by Andy at aero Hobbies in Lewisville Tx. Gyro is a futaba 240. I've never had it out ou HH.
I had a servo go out. Figured it was a good time for some pm and tuning. Replace servo, balance blades, adj linkage rod to tail. I've never gunned the throttle before. When I did, the heli would rotate about 45 degrees before hh locked tail in place.
Barracudahockey advised me some time ago to dump the tt36 and get the os37. Excellent advice. I like that engine. Since breaking in engine, there has been very little carb adj needed. Try that with a tt engine.

RE: from hover to full throttle
 

I have read some of the posts the Barracudahockey has to leave and he is right on the money. I run the 37 on my C30 and it is killer.

RE: from hover to full throttle
 

Y'all are making me blush.

Just bored at work and trying to pass along what I wish had been passed along to me when I started.

RE: from hover to full throttle
 

I think its just the tail's normal response to the torque effect of the blades being accelerated. Until the tail is up to speed the gyro can't do much. Mine always does this if I accelerate a little too fast. If you keep acceleration slow you won't notice it because the skids have enough traction to prevent the heli from rotating until you have headspeed and gyro response.

RE: from hover to full throttle
 

It's not the traction of the skids on the ground as I don't gunn the throttle until heli is in a hover.
Butt thnx for the post

RE: from hover to full throttle
 

I wish I had a job where I could play around on the internet and get paid for it. [sm=sunsmiley.gif]

RE: from hover to full throttle
 

I hope you stay bored at work! It's good for those of us who need help!;)

RE: from hover to full throttle
 

Well here are some possibilities.

Gyro gain not high enough. If your maxed out move the ball out one hole on the servo arm, decrease the gain and start again.

Tail belt too loose or too tight. Too loose and it could be slipping. You might want to pull it and inspect the teeth for worn leading edges. Also inspect the tail rotor shaft pulley for wear.

Pitch throttle curves allowing the head to over or under speed at full throttle.

RE: from hover to full throttle
 

I don't recall the 240 specifically, but make sure that if it has limit adjustments, that they allow the rudder to move from extreme to extreme on the tail rotor pitch slider. If the range is too low, then the gyro won't be able to put in enough tail pitch to compensate for the sudden surge in torque when you punch it.

- Tim

RE: from hover to full throttle
 

Nope just gain and heading hold/non heading hold and direction. Make sure your getting full throw on the tail pitch slider, the best way to do this is to use a blank servo wheel with a hole custom drilled to give you max throw without binding. You may have to sacrafice a little throw in one direction, thats ok you want the arm (or a line drawn from the servo spline to the ball hole) 90 degrees to the tail pitch rod at hover, thats more important than equal throw but you don't want it to bind. More throw in one direction is fine as that is the direction you are fighting torque, the other way your just letting the torque of the main rotor system spin the nose.

RE: from hover to full throttle
 

In a HH gyro, throw limits are NOT set by ATVs, the ATVs only affect the maximum commanded piro rate (The "Angular Velocity" part of the "AVCS" moniker that Futaba uses to describe it's HH gyros . . . ). The gryo itself limits how far it can make the servo travel to attempt to fulfill that command. From looking at the GY240 manual, it appears, unlike the 401 and above, to not have an adjustment. As such, the way to get it setup correctly would appear to be to use a servo arm that will allow the pitch slider to make full travel. When a heli is sitting on the ground, and you give it left or right rudder, no matter what the ATV, in HH, it will go to full travel in the specific direction, in an attempt to fulfill the yaw rate command. If you don't beleive this - try it . . . .

RE: from hover to full throttle
 

That better?

RE: from hover to full throttle
 

Much! This hobby is confusing enough at times, without getting bad advice . . . . . and trying to set endpoints with an ATV setting in HH can get your setup mighty buggered!

- Tim