I was at the north airport in a tower waiting for a friend to return from AFK. We then decided to carry on moving, i was lying down in a wood tower. I turn around, scroll and click climb down.
My character then stands up, sprints 2 steps, lands on the ground, i then go into the climnbing animation and die instantly.
I havn't lost any blood, i was lucky early on with an axe and supplies so i know i didn't loose any health. Fall from that hight should not get you killed, maybe a 1/10 chance to break your leg.
The sprinting thing was the same as if you stand still and press lie down, it sometimes does a weird little run and then throws himself down.