Invisible balcony?

Zoomed in on one of my airports and I guess there was an invisible balcony installed. I’m not sure but I think this is some sort of OHSA violation. Or perhaps these two travelers have the power of flight. But then why would they be at a damned airport!?

Minutemen vs Vertibird

So, in anticipation of defending the Castle from a significant Institute attack, the Minutemen called in almost all of their recruits as backup with myself included. A group of them had garrisoned themselves on top of one of the walls and I decided to join them. During the calm before the storm, I noticed a Vertibird attacking something on the ground though I did not see what exactly. As I’m no fan of the Brotherhood, I decided to do some target practice on it.