Cube Black testing

I have a new cube black and think have followed the SB instructions. I tested the cube many times and did not get any “cube black warnings”. I knew the risk and I flew it with gloves,leather shoes & a coat in May. I have a video and a log file so you can see exactly what happened. Again I knew and accepted the risk of a test flight.

On the test flight I was in loiter, I gave the pitch and roll stick a small twitch and it rolled hard back & forth and leveled . I gave it another bump and it went crazy and somehow regained level flight again so I quickly landed it. Obviously I will not fly this again unless you can find where I have made a mistake in the setup.

This cube has had about 2 hours of successful flight then I had this same issue in auto.

https://www.dropbox.com/s/wcmk3cetciipzg7/hextube.mp4?dl=02019-05-17 16-14-52.bin (1.3 MB)

A quick look,
You have an imbalance in the RCout between the CW and CCW motors.
20%20am
Are all the motors level?
Props on tight? (a slipping prop?)
Flex in the arms?

There is a large yaw oscillation which might be twisting arms, hard to say.

How does it fly in Stab mode?
Have you auto tuned ?
It might be worth not giving it full stick deflection in testing as it seems well power and capable of very quick reactions.
The fact that it recovered from the oscillation is good.

Sort out the CW/CCW imbalance then auto tune and it should fly well.

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Thank You, I think I may have overpowered this frame. It it very straight, tight screws with T props but it does have more twist in the arms than other frames. I looked at the frame closely when I noticed cc/ccw imbalance in the motor temps.
I think you solved this for me. The frame is no good.
I have not auto tuned yet.
How much twist is acceptable?

Good assessment! Best to get it tuned :slight_smile:

Unrelated to the SB btw,

Aeroelasticity is something that is inherent in all machines.
The acceptable amount depends on flight performance.
You can always add a bit of weight (bigger battery?) to tone down the power to weight ratio.
Do a hover test and see if you have as much oscillation.
If it gets worse then I would doubt the frame, but if it doesn’t,
Then try a sedate autotune.

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Glad you are here. I can give good advice on thing. Wiki stuff finding correct parameters and stuff. As much as I try I can’t read logs as good as I have seen you do it over the years

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So great to see you here Mike!

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