The Blue Angels do something at airshows called the "diamond 360 maneuver," where they fly in formation . . . with their wings just18 INCHES away from each other.

 

 

And if you want to see what THEY see, you're in luck.  Because there's a new video shot from one of the cockpits.  (Search for "First Person View of Blue Angels Practice."  You start to get an idea of how close they are around 10 seconds in.)