The upper bunk. But it takes some real determination to keep knees bent or leaning forward until you black out. Possible a "cannonball" type tuck and jump. It has been done before. Suspicious, but not impossible.
Yeah, I've tried to imagine that. Maybe I'm just lacking in imagination.
Here's my problem - let's say the upper bunk is 4 or even 5 feet above ground. You tie the sheet around your neck and the other end to the upper bunk - say generously, 5 feet drop all together. You fling yourself off of the upper bunk, and the minute your feet hit the ground, there is not enough pressure to break your neck and kill you. So, you go limp to try to suffocate yourself. When you pass out, or even before that, your feet and/or knees are on the ground taking much of the pressure off of the neck. Is there enough pressure for a 200 lb man to suffocate himself that way?