It was pretty mild here today so I took the X85 out to see how it flies. I didn't notice I had taken off with a 1/2 dead battery until I took off. I was also distracted by  flying into the sun. ( cheap camera ) Under acceleration it is nice and stable but trying to just decrease altitude while hovering it gets into a "Death Wobble" that is really hard to recover from. You can see it in a couple of places in the video especially at 1:35.  Throttle will usually get you out of it but that makes it hard to land sometimes.
Here is a shot of my brushed quads. The red ones are 100's with 8520's and 65mm props. I started with the shrouded one but it also has the Death Wobble under deceleration with little forward movement. I moved the FC from the shrouded red frame to the other red frame ( Basic X ) same FC, cam , and props and it flies great no wobble at all. But not so good for indoors.
I did switch to 'props out" it helped a little bit but not enough.
Is this a know issue with shrouded setups or is it just that my shroud design sucks.
Do we know what causes this ? Or how to mitigate it ?

Any help would be greatly appreciated !



And the video

looks normal to me, micro quad this size does wobble if you decent vertically... it's just like prop wash on a 5" quad, but more pronounced on a micro since it's so much less powerful. As long as you fly forward it shouldn't do that?

Hi Oscar Thanks for the reply.
Yes it is only a problem if there is little or no forward movement. But the thing that gets me is if I move all of the hardware to the non-shrouded frame the wobble disappears. Same wheelbase, same hardware. This leads me to believe it is the shrouds.
I have never flown a real whoop or any commercial shrouded quad so I have nothing to compare to. I do appreciate your input it makes me feel a bit better about my design.
Also, it is not much of a problem indoors which is why I built it.

Thanks again, I am really enjoying this and your site.

Scott

two things i can think of:
- with the ducts you have more weight distributed evenly across the horizontal plane and it makes it harder to stabilize the quad. It's also easier to stabilize when the quad is lighter
- "dirty air" interferes with the spinning propellers more effectively with the ducts... making the quad less stable

Thanks Oscar
I am going to go with the "dirty air" hypothesis . Even a little forward movement will stop it. I guess it is getting out of its own prop wash. I had played with adjusting COG by moving the battery on top. It handled different but still wobbled on decent.
So I guess the real answer is "go faster"

Thanks again

Scott