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Old 09-09-2016, 09:34 AM   #45 (permalink)
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Join Date: Jun 2015

Originally Posted by Chris DeSain View Post
Got mine today and I have tail hold issues in any mildly aggresive pitch type change positive or negative upside down. I have two 230s and 3d the crap out of them and my tail holds fine with them ? Same transmitter configuration so I am really stumped why my tail won't hold. I am in 3D mode
anyone else with this issue right now it is scary to fly dealing with the tail.

45C 1300 pack
I know that is frustrating. A few things to check. I know your heli is new, so many of these may not apply. I know that most of you know this stuff already. I am not trying to play expert.

I chased some tail blow out in my 230 S. Some days it held solid, and some days it did not. I could not believe that this was just environmental influences, so I experimented. Anything that imparts a rotation force, or a vibration, appeared to increase my problem. Some things I experimented with.

Gear mesh: While too tight is hard on your motor bearings and causes friction, too loose causes a backlash. That little bit of space relates to a delay in gear contact, and a spike in rotation force when the teeth 'collide'. I purposely loosely meshed my gear (lot of backlash) and tested. The tail response was sloppy. Some good methods of meshing are posted here already.

Blade balance: Stabilization units hate vibration. With optional carbon fiber blades on my 230 S, after they got some tip damage, the heli started flying differently, including tail blow out. I put on new blades and the tail held.
2nd scenario, I put on a new set of blades and the tail was sloppy. I checked the balance on the blades and the center of balance was off. They matched over all weight, but the centers were off. I matched centers, then balanced and the tail held. (yes, new blades can be off). Many people don't balance blades. On smaller helis, I usually don't unless I suspect a problem. Remember to match centers first if you do.

Blade Grip Tension. For A23X helis, I never completely figured this out, but, I made some observations. If the blades are really loose, and there is a head speed change or change in disk loading, the tail lags (blow out). If the blade grips are too tight, the tail seems twitchy, and ultimately blows out in a hard maneuver (change in disk loading). I understand how the physics of this can cause a surge in rotation force, but don't really have a method of getting it right. (I just tightent them until they feel right) In non-technical terms, I just know when mine are too loose it flies like crap, and when they are too tight, it flies like crap. On my 250 CFX this morning, I loosened the grips way too loos on purpose, and the tail was all over the place.

Main blade grip dampeners. If they wobble too much... A23X does not like it. They do wear out.

Tail rotor not true. We have all done it with the three blade "fan tail" rotors. Bend the blades back after something caused them to not be true. (close one eye, and look at the edge and bend the blades back in alignment.) But I have noticed that once the rotor is not true, or I have done this a couple of times, my tail starts to misbehave.

Tail rotor on wrong side out. I know yours is new, but there was a post in the 230 section about a new tail rotor being on backwards. This will really cause one to fly funny.. (Including possibly damaging your tail motor). They look backwards, when on correctly. Shiny side out. I just always look at the pitch and curve. Position one blade straight up. The curved edge should be towards the rear of the heli. If in doubt, look at the picture on the box.

Flat throttle curve verses V Curve. Some have said one is better than the other for maintaining tail hold. I have not tested, maybe someone else has a comment here? (maybe I will test that today) I am using flat throttle curves for IU1 (80%) and IU2 (100%).

Tail Rotor Gain: I use defaults at 100%. Since there are people flying defaults and have a manageable tail, I would not think this is the problem. Maybe someone who has adjusted the Tailrotor Adaptive Filtering could tell us about their experience.

Situational: There are situations where even a well working A23X with Tail Motor will have a tail blow out. I can cause mine to do it if I want to demonstrate to someone what it looks like. Fast Forward Flight with a tail wind, hard vertical decent with negative collective, hard elevator up, hard positive collective. The tail "vrrr" turns into a "vreeeeee".

Please, other people post what you did to improve the blow out. Maybe we should start a thread, "Managing the Motorized Tail"
Blade 450X, 450 3D, 270 CFX, 300 CFX, 250 CFX, 230 S, 200 SRX, 180 CFX, Nano CPx, Lynx 300 Scratch Build, Spektrum DX9
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