Hi, I have the following issue on a 550 T-Rex.

For training reason I have the stab mode in Koax setup for testing pos hold and alt hold.

It flew perfect but after about 2 mins flt time no drifting to the left side was possible, Nick forward and back and bank to the right side was still ok but left side not. After landing no tilt to left side was to see on the swash-plate. In normal mode everything was ok. I tried it several times and every flight the same outcome. At about 1-2 min after switching on stab mode no possibility to bank to the left side. What to do.
Vibration level was low.

Hi, I did not receive any help. Is problem not known?

Hi,

unfortunately it is hard to imagine how the problem look like. No, it is not any known problem.

Theoretically the problem could occur if there is very strong wind from one side. But this is unlikely if the problem occur each time.

Then there could be a problem if neutral position of the servos and swashplate is not zero. This can be verified by enabling Servos/Subtrim (tuning) menu. All servo arms, swashplate should be centered as close as possible. And also there must be 0° between main blades.

Is the model drifting during this mode?

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Spirit System developer

Hi, no the heli is not drifting. I tried it on perfect wind conditions, just 5 km/h from south and I was flying heading north, so wind from behind.

When I start it is perfect to fly with bank to the left and right, so drigting to each side is possible. After a while no correction to the left is possible just drifting to the right or nick forward and aft.
When I turn the heli to the left by about 90 degrees I can come back to the helipad but still no possibility to drift to the left. I tries all directions so windeffect is no factor. When I land and reconnect the battery erverything is normal for a while and then same problem occurs again.

Do you think a new software uoload will help?

greetings

Hi,

I think that new firmware flashing will not help.

Did you verified neutral/center position of the cyclic servos and swashplate? The best to verify it is in Subtrim (tuning) menu.
This could cause problem if it is imprecise.

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Spirit System developer

I will perform a complete new setup and I will report the outcome. Cheerio.

I recommend to check this page:
http://manual.spirit-system.com/index.p ... tive_Pitch

This could help a lot to configuring the model precisely.

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Spirit System developer

I have yesterday carefully redone the setup process mechanically. It is all correct but the issue is still there.
I wonder that the drift problem occurs after a flying time of 1-2 minutes. In the first minute everything is fine.

Ah, that is sad. Do you have a fan on the ESC?

You are saying drifting - does it mean that the model is drifting or it could hover at the single spot?
Because if it is drifting then we are closer to a solution.

In this case this can be helpful:
http://manual.spirit-system.com/index.p ... ise_Rescue

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Spirit System developer

Installed is the hobbywing 100A ESC with original Fan.

Actually I mean a controlled move to the side with the aileron (cyclic) stick. When I hover over a position to land or just to hover I need to swing to left and right and forward and aft to control the position. I can steer all axis but not to the left. So I drift always away from my position and cannot control it back to the left side.