I cannot find the source sadly, but there was a video/gif around a while back, where someone climbed over a railing and the character tried to basejump and just died because well it was more like waist-high.

The same thing still is happening. I had just been on the roof of the liberty airport and if you have your back pointing towards the runway on the right hand side there are three 'bars' coming down from the roof to the small walkway below. I wanted to climb over them, close to the ledge and at one the character just basejumped and instantly died by touching the little ledge. Luckily this happened after I cleared the whole area and oh joy had to do it all over. How about adding a timer of you have to be maybe two to three seconds of the ground before this happens.