So, my brother and I just experienced this on DayZ US 5136315 (if there are logs for that server that could help) around 21:00 today. We found an Ada 4x4 in need of repairs and my brother decided to get into the car to check fuel levels and the other gauges. As soon as he got in, the vehicle started to lift off and shake around, eventually flying away. While it was a funny sight to behold from my perspective, from his perspective it was impossible to get out of the vehicle in time and eventually his screen went black as he went unconscious and died from the violent shaking. At one point, the car must have been 100 feet in the air and flew maybe a mile or two to the east of where we found it. I chased after it in an attempt to get his gear, but it was upside down and could not be interacted with. So, he lost a lot of valuable loot which equals many hours of time spent. It will be even more hours spent running across the map to get to where I am, so he is extremely frustrated and put off by the game now.

While I understand that there will be bugs, this is quite frustrating to see in 1.0 - especially after finding this nearly two year old task!

Anyways, if there's any other info we can provide to help get this fixed, let me know.

Yesterday on the "SNG 1pp exp server experienced the opposite: The ADA also spun and whirled after boarding (only on driver seat), but came to a halt after standing still (30-60 sec.) Under the map was impossible, the physics was like not existed.When leaving the vehicle, it first looked as if you fell deep under the map, but you suddenly landed on the ground "over the map", which almost always in lie-position, we tried all 3 players, the same experience for all, even after relogging.
Edit add: My system are Win7 the system of the other 2 mates are Win10, time CEST 16.12.18 ~ 21:00 position the ADA spawn on Troitskoe.