Hello,
I tried several approaches but the problem is not present for me, could you please upload a short video displaying it clearly?
Thank you very much.

Ok - I tell you exactly what I did:

1. Open Editor and select a island
2. Place a UAV Operator and a Hummingbird (works with other helicopters as well)
3. To create the UAV use the following example below of the command: https://community.bistudio.com/wiki/createVehicleCrew

(I used as UAV: B_UAV_02_CAS_F). You can also place a UAV and hack it on the spot and let it take off - works as well

4. Connect to UAV and tell it to loiter
5. Connect to UAV turret and lock on to your position
6. Get in the helicopters pilot seat and open the turret again
7. Watch you bounce and how the helicopter explodes

Note that the advanced flight model is enabled (all options set to enabled)

Video on youtube is here: http://www.youtube.com/watch?v=NfAtAWjJIkU

Hope this helps.

wanted to test something else, and reproduced it by accident
this issue is propably caused by you swaping control when accessing a uav from a crew position (http://feedback.arma3.com/view.php?id=22582), and the unability of ai to cope with afm; or rather a glich, that occures when ai has to cope with afm

i have noticed, that this issue even occurs when the engine is turned off. (see my vid in the attachment)