Simulating Physics on Flying skeletal mesh causes problems

I am trying to create a semi realistic flight sim game, Currently I have a control set up but it feels to light and snappy for my tastes
I have tried to use the physics UFO BP from the content examples because it has a nice weighty feel and also adds inertia to any direction im moving in.
The UFO Bp has a single static mesh and single collision box and is set to simulate physics. But my craft is a skeletal mesh and as soon as I replace the static mesh with my skel mesh it is freaking out & spinning out of control.

How can I make it behave like the static mesh ? whats the issue?