“But why those patterns? Can’t help thinking it means something.”
As someone pointed out, safety is going to be the primary
consideration. They need places to crash if the worst happens.
They need room to make their turns and returns, at the speeds they will be moving.
Too many considerations to allow much room for covert flight
path messaging / signalling... ;-)
“But why those patterns? Can’t help thinking it means something.”
________________________________________________________
“Look here, not there”. Maybe something was going on while everyone was looking up at the planes. Just my guess.