It's a joke silly! We've been saying that since I was a child. It's not just for planes but high falls in general. When you're falling just wait 'til you're 2 feet from the ground, and jump from there! That way it won't hurt! Get the silliness in that? ;)

Fair enough... But I won't be jumping from any high heights to see if it actually works. :D

But what if you land at the far upper-eastern edge of a football-field. You would die, but it wouldn't be the center. Or is it just that it doesn't mean an actual field, but rather a circle of any size of which you are the center? If so, then naming it a 'field' confuses me.

<span style="color: lightblue">A field is any patch of land. ;)

It's a field and this paticular person falls to the centre.