I am flying a Bell 230 Turbine for a friend and am having problems with the tail wagging in a hover. The chopper was purchased used and with no problems from the previous owner i.e. No Tail wag. I have a 9z radio and am having trouble setting up the gyro through it. If anyone has a setup to walk me through it would be appreciated. I am familiar with and own a 9C and fly and setup choppers for many people but this has got me stumped and trying to read the 9z manual seems like a foreign language. Thats why I think the problem lyes within the radio. The servoe is sheilded from the heat of the turbine and the gyro is in the front of the chopper. I have the Gyro Sense set on dual and have tried rates from 30% to 100% with only the width of the oscillation widening or narrowing but never going away. ATV's are set at 100%. Delay on the gyro set at 0. I have not tried moving the link in or out on the sevo yet do to it flying fine for the previous owner.

Any thoughts or ideas would be greatly appreciated.

Radio -------------- 9Z
Vario --------------- Mechanics
Turbine ------------ JetCat P120
Servoes ----------- Cyclic Fut 9204
Tail Fut 9402MG
Gyro ---------------- Fut 401
Head Speed of 1400 - 1450

Go to the servo screen in the radio and move the controls around to see if there is some movement, which means there is some mix still turned on. There are mixes that are on by default in that radio which must be hunted down and killed with much violence!!

I am setting up two Twins for the canadian government using a 9Z and after much cussing and pulling of hair, got it figured out. Unfortunately, it was entirely by mistake or luck and cannot tell you exactly what I did, except to look in the servo screen for movement.

Good luck!!

Chris D. Bergen

Originally the gyro was set in DS mode after finding that it was not a digital servo I switched it, witch made the Wag more tollerant. The are no mixes active as now I almost know the Radio better than my wife.

Thanks

I LOVE THE SMELL OF JET FUEL IN THE MORNING

Originally the gyro was set in DS mode after finding that it was not a digital servo I switched it, witch made the Wag more tollerant.

Be careful here. DS mode can ruin non digital servos. At a minimum I would not use that servo any longer for such a critical function. It's worth it to think about putting in a 9254 or some other suitable tail servo and protect that expensive bird.

nick

By not using the 9254 servo you may have to play with the gain and the delay together to get it working right.
With the 401 if you have it in heading hold the red LED should be on steady.
When you move the sticks around and try flipping all of the switches on the TX (except for the rudder) the light should stay on steady at all combinations.
If it flickers at all the there is some mix happening that you must find.
The LED will blink any time that the rudder channel is not on center.

Jeff Borowski
RAMS Club President
www.ramsrcclub.com

I had this problem with my Predator Turbine when I first flew it. I had all the same gear as you have, and I messed about with gains, delays, digital switching, end points and throws. With a lot of fiddling about I managed to mask the problem but I knew it was still there but couldn't figure out what it was.
It was then that Paul Heckles said, the thrust races it the tail blade grips could be round the wrong way, and you know what , they were.
As the tail span up the blade grips were binding and this is what the servo was fighting against causing it to hunt.
Just a thought.
Let us know what it was.
All the best, Bell Bloke.

some gyros may have a pronlem operating correctly with a turbine running. On my KingCat ( Jet not heli) I had a 401 gyro on the nosewheel. WIth the turbine running, it would wag the nosewheel at a fast rate very slightly... i ended up not using the gyro, but this could also occur on a turbine heli. Make sure the gyro is as far away from the ECU, or fuel pump as possible.

Wojtek