Newbie question...

[jgriffin_iii]

I have been trying to learn this stuff for over a year now.. still a newbie though ;) ...

I have a trex 500 FBL using the 3G setup (version 3.0) ... I am finally at the point where I can take off nice and smoothly and tail-in hover 'reasonably well'. I have noticed that if I release the cyclic, the heli drifts to the left constantly. I understand that this is just the nature of the physics involved in helicopter mechanics, but I would have thought that the FBL system would detect the movement with no cyclic input and correct automatically...

Should I

1.) Play with the gain on the sensor and see if I can make it correct?
2.) Use the Trims on the radio to null the drift out?
3.) Live with it and continue to train myself to adjust for it ?
4.) something else clever that I haven't thought of yet ;)

Any help would be greatly appreciated.
John

[CSpaced]

Ok, I finally got a minute tonight to sit down and reply! :D

Was there a crosswind blowing when you noticed the drift? Very rarely can you let go of the sticks and have a heli stay hovering in one spot, they constantly need correcting even on a well set up heli.

That being said, they shouldn't drift by much. If it was moving significantly, then it is likely a setup issue.

I would start out with your mechanical setup. With a linear pitch curve, and your throttle stick at mid stick (and all your subtrims at zero), check to make sure that your swashplate is absolutely level and that all your servo horns are either parrallel or 90 degrees to the servo (depending on the setup).

Once this is done, I would go back through the 3G setup - follow the manual step by step.

When you power up your heli, it's important to keep it very still until it finishes initializing.

I would leave the gains alone for the moment, until you've verified everything else.

You might be wondering why you can't just fix it with a little trim? This will just mask the problem, and will make for funky flying characteristics when you start trying out new maneuvers.

If you think of anything else, let us know and we'll help you figure it out!

I made a video a short while back showing how I set up the swash.

http://www.youtube.com/watch?v=e2SavMUPTns&feature=player_embedded

[jgriffin_iii]

I don't think it's a set up issue on the swashplate, I was pretty careful to be sure that it is level when I set it up. The drift isn't bad, just noticable. My question was more about the FBL system, isn't it supposed to compensate for uncommanded movement? I have certainly noticed it when a gust of wind hits it.

[CSpaced]

I don't think it's a set up issue on the swashplate, I was pretty careful to be sure that it is level when I set it up. The drift isn't bad, just noticable. My question was more about the FBL system, isn't it supposed to compensate for uncommanded movement? I have certainly noticed it when a gust of wind hits it.

It does to a point, but it's not like a co-pilot that will lock the heli into place and keep it there. If it is only a minor drift in some wind then I wouldn't worry, especially if you are certain that it is all set up correctly.