X50. "wo wo wo" sound when you flying..?

[DavidTan]

Torque Tube version
I had a tail explosion due that, explosion twisted the torque tube and killed my bls 251 servo, tried plastic blades, cf and all sorts of gyro settings plus repositioning. changed servo horn position. changed to another gyro too.

After crash rebuild
Changed new bls servo, gyro, new torque tube drive shaft,booms and bearings, new gears(even tough they did not strp), tailshaft, tail case bearings, and changed to the Titan SE sus hub, angular bearings with plastic grips.

Still the same problem, a friend of mine broke the the control rod in flight due to the bad vibes, it only occurs above 1700 rpm. Please if theres a TT rep any ideas on this?
I did not have all these funky issues with the Old Titan Se.

[DavidTan]

Fixed Tail vibes issues.

[crashburn]

How did you fixed it DavidTAn?????

[Danorn]

Yes David do tell, I am grounded until I get this solved

[DavidTan]

Use 3 torque pipe support bearings(thouse Red rubber things with bearings) and space them out at different distances through out the torque tube, they should NOT be equi distance. And cable Tie a small piece of fuel silicon tube onto the tail fin. The cause was the torque tube becoming a musical instrument which resonates all the way down the boom and amplified at the tail fin. I think its called harmonic resonance or something. Single and or 2 bearings was insuffiecient for my heli. After mod Heli tail flies normally with any gain and setting .. no kicking, drift and works at any gain. even at 2100 + overspin the tail still works normally like a titan SE. The trex 600 torquetube single bearing supports were of harder rubber though. No more Woo sound at any rpm. Hope this helps. It could my heli build problem but that fixed the Woos for me.

[carlos]

I have noticed if the engine cooling fan has and run out the vibrations tranfer easily through the heli, even if the motor is running a little lean on the low mixture the vibrations are worse.
TuM I believe the poor tail performance on the tortube version is the VERY flexible tail pitch lever. My belt drive version has the old TT case and lever which holds very well. I can not say the same for my TT version.

[crashburn]

many Thanks David I will do the same on mine and give you a feedback as soon as.
Have good flights,
Xavier,

[DavidTan]

Originally Posted by carlos

I have noticed if the engine cooling fan has and run out the vibrations tranfer easily through the heli, even if the motor is running a little lean on the low mixture the vibrations are worse.
TuM I believe the poor tail performance on the tortube version is the VERY flexible tail pitch lever. My belt drive version has the old TT case and lever which holds very well. I can not say the same for my TT version.

Hi Carlos,
Yea thats true like u suggested, can be a fan runout isssue, or unbalanced tail blades. Ive seen many X50 TTubes version on youtube that fly great out of the box. Its the best heli ive flown so far, not comparing to other brands or anything. Thanks for the tips ill go thru the other parts again and post a vid if i can.

Cheers
David

[DavidTan]

Originally Posted by crashburn

many Thanks David I will do the same on mine and give you a feedback as soon as.
Have good flights,
Xavier,

Hope u can resolve the vibes too mines working great now. Looking forward to your feedback. One of my hobby shop friends contacted a TT pilot and tipped that it runs great on 92mm cf radix blades. Ill give it a shot soon. Have a good flight too.

[DavidTan]

Finally i got some help from some really helpful TT reps thru my local hobbyshop , it appears it was not a kit problem but my assembly. Heres the fix with no extra parts required.

Fixed torque tube vibes, after a few issues. NO EXTRA PARTS OR DRILLING required.
If u get Torque tube Vibes. This will help!
1. Ensure that the Torque tube drive pipe end is properly seated all the way in on the REAR bevel gear.Inserted as close to the end until u can see the metal tip at the rear bevel gear hole but not binding the tail bevel gears too thight.
2. Try 85-92mm tail blades. 85mm worked best for me.
3. Ive Tried 1 or 2 or 3 support bearings on the tube pipe it really does not matter.
1 support bearing is enough, ensure it is NOT centered on the tube, build according to manual 350mm from tube tip end facing tail case is correct!
Have fun flying! The X50 Torque tube version flies light, agile and feels good in the air!
Tail electronics Gy520 Gyro + BLS 251

[Dan893]

I know this is an old thread but is this a confirmed fix for the tail noise/vibration. I had this happen and I added 2 bearings and it seemed to help and stopped the vibes at certain head speeds but not overall. I was flying after adding the second bearing and thought I had it sorted out then as I was doing a pass I heard the wo wo wo noise and a loud bang and a tail blade was ejected. I was able to flip the throttle hold and auto it safely and upon inspection the whole side of the hub that came of had actually cracked that side of The hub off

[skytrekin]

good info here