There are a few character animations in vehicles, let me show you a few...

All the screenshots are uploaded in the correct order below.

#1 (Probably the most annoying)
http://imageshack.us/f/801/2013051700007.jpg/

This happens if you and someone else try to enter the heli as co-pilot at the same time. You will be stuck in this position until you die.

#2 (He doesnt only stand on a quad at 28 Kkm/h, no, thats not badass enough. He also pretends to hold a pistol.)

http://imageshack.us/f/96/2013051700001m.jpg/

I have no idea how this happens, seems to be random.

#3 (Believe it or not, hes alive.)

http://imageshack.us/f/853/2013051800005.jpg/

#4 (This is me driving on a quad. Apparently you dont need to sit in order to drive a quad. This had to be the most awesome quad-ride i had yet.)

http://imageshack.us/f/11/2013051800002.jpg/

#5 (This one is definitely the best and deserves more than one screenshot.)

http://imageshack.us/f/854/2013051700010.jpg/
I think this happens if the guy in the backseat disconnects while you are driving.

http://imageshack.us/f/211/2013051700012.jpg/
Yep, its his hand.

One last screenshot...
http://imageshack.us/f/13/2013051700013.jpg/
*Hey, sit down, i will warm your butt*

The following reports can be found in the comment section:

Akinari-san:

The first one: 1st Person in a car, have only seen it in a Hunter though, your character has his eyes on the belly, making it impossible to drive or anything, seems like this happens when your character looks dead while being still alive inside a vehicle.

The second one: 1st and later any person in a car, only seen it once in a Hunter though, you can litterally see inside the textures of the car and when you exit the vehicle you will fly for a few meters hitting the ground hardly and hurting you.

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