Airliner Walkthrough Left 4 Dead 2

Name of glitch: Airliner walkthrough on left4dead2
Gamertag: SavageBossBoss

on the second level of swamp fever,there is a plane crash that u need to open a door to cause a lot of zombies after u, well all u have to do is jump onto the plane chair to your right and keep jumping up, try to get onto the two black windows then just walk right to the other side. walk through the campaign so the computers will spawn next to u.