Originally Posted by
zkzkz
"dangerously close" can't possibly be the correct phrase. What danger does being over a kilometer from a plane pose?
Depends if you're also in a plane or not. And possibly something to do with plane sizes and wake turbulence. But that's best left to the experts to answer.
I'd certainly want to at least be inside a plane when a kilometer from another airborne plane, though. Or have a reason to be out there.