Tail issue with Tarot ZYX

[kdrcguy]

I have upgraded to the ZYX about 2 months ago and I like it a lot. It is great for sport flying but I have found a problem with it doing more demanding stuff. When I do heavy + and - pitch pumps the tail blows out and the heli starts to turn to the left on its own. I get no blowouts in heavy single pitch pumps but up and down it really starts to show.

I would appreciate your input on how to solve this issue because I will be getting into doing more 3D and I would like a capable bird.

Today I was doing tic tocs for the first time and the tail does not hold for very long. I ended up flying my bird to the right and recovering.

I realize the I can set the Tail Compensate Collective to Tail parameter, and I have tried it, but that gives me a tail jump to the right with a heavy pitch pump which is not desirable, but may compensate for continuous pitch pumps.

Here is my setup:

Blade 450 3D
Tarot ZYX controller
Tarot FBL head
Hitec 5065MG cyclic servos running 6V
Hitec 5084 tail servo running 6V
Scorpion 2221-8 V2 motor with 11t pinion
CC Ice Lite 50 ESC no gov
Align 325F CF blades
KBDD tail blades
Stock rx
Align Trex 450 Sport canopy
100% TC
Linear PC in stunt mode
12 collective pitch
10 cyclic pitch

ZYX Settings:

Main Rotor

roll pitch
p 65 65
i 90 90
d 30 30
accel 125 decel 55
rc dband 40 gyro dband 4

Tail Rotor

p 75
i 50
d 0
accel l 125 r 125
decel l 30 r 30
rc dband 60 gyro dband 4

t comp cyclic 0 t comp collective 0
zero pitch 0

Main Rotor

roll
agility gain
40 40

pitch
40 40

Tail Rotor
yaw l yaw r gain
40 40 100

Radio DX6i

aile elev DR 100 Expo 15% (stunt mode)

travel adj 100%

gyro
69% HH
30% rate (not used)

flight time 4:30 min

Thanks for your input.

[InFocus]

The only thing that catches my eye is 10degrees cyclic deflection is more than I've heard others do. Would this cause more torque to be placed on the heli? What happens if you make that 7.5 or 8degrees?

[kdrcguy]

I have tried it with 8 but I didn't try hard pitch pumps with that setup. I don't think that would be the case. I set it to 10 cyclic because I spoke to a pro pilot at my club field and he told me that about 10 cyclic should be good for 3D so that is what I went with.

[Mikej]

I haven't tried the Tail Compensation as I haven't needed to fortunately, but that is where I would start - if it was giving you a kick to teh right it sounds as if you had too much.

Have you tried asking in teh RCG threads - there is a lot more info about these uints over there currently (in 2 or 3 different threads) and a search of these would probably give you the answer that you want.

Cheers,
Mike

[Dr. M]

Definitely add some collective>tail and cyclic>tail compensation. I've got 4 points each on my 450. Make sure it compensates in the right direction, if not, reverse the sign. Tweak up or down by test-flying multiple continuous rolls or flips. To test compensation direction, start with your collective stick at 0-degrees (in throttle hold). Then push max +ve collective and watch the tail: the leading edge of the tail blades should move towards the boom just a little bit.

[kdrcguy]

Originally Posted by Dr. M

Definitely add some collective>tail and cyclic>tail compensation. I've got 4 points each on my 450. Make sure it compensates in the right direction, if not, reverse the sign. Tweak up or down by test-flying multiple continuous rolls or flips. To test compensation direction, start with your collective stick at 0-degrees (in throttle hold). Then push max +ve collective and watch the tail: the leading edge of the tail blades should move towards the boom just a little bit.

Thanks for the suggestion. I have tried cyclic to tail compensation before and had no luck. Your suggestion pushed me to do more compensation tweaking today and I got it to fly good now. No more drift on negative pitch. Thanks.

[bpgoa]

Hope this is useful.

If you are over pitching and bogging the head, no gyro in the world will compensate.

You could also look at your tail linkage and servo. If stiff, slow or weak then it will lag the gyro demands.

[bpgoa]

Ps. For learning 3d. 8 degrees of pitch is better. It'll give you finer control. When you get real good at 3d you may want more but most would change blades to lighter/ more inboard c of g to get faster roll rates