Bone size is too small to create physics assets

Hello everybody, i’m a newbie in UE4 and Blender.

I use blender 2.79 and UE4 4.17.2 versions, and the problem is the bone size too small…

I have tried every solution to resolve this problem, from x100 scales (.01 metric) to anything i read in any forum, but in the end no one worked or maybe i did it wrong. (Those solutions were from old versions, i don’t know if it work in this version).

The only one that i didn’t try is the physic asset manually from UE4.

As you can see, my model is an aircraft with his rigging and an animation there (Everything was fine before i put the animation, now i can’t even change the alien plane into this aircraft because i can’t find the model. Another Warning, i do import the animation separated). And this one doesn’t have the scales x100(0.1 metric).

So the first problem is how do i resolve this bone size too small.

The other problems is some question,

  1. Actually i’m confused, do i really need to create physic assets to make animation for UE4? Because from what i know it’s just physic and collision.

Thanks for the answer.