Good question, not sure how they're organized, but they probably have squads or something that specialize in different things. Not sure if they have organized branches like, airforce, navy etc. They always seemed more like post apocalyptic knights, with all of their chapters and stuff, but I don't know a lot about their organization to be honest. But they do give off the sorta templar vibe.

The only BoS chapter with the capability (i.e. manpower and enough power to get resources) to make airships is the MWBoS; and they're practically not even the BoS anymore; at this point I'd be surprised if they weren't a full blown state. As for the others, out West they're almost extinct and on the run and out East they're confined to the Citadel.

I'd bet if those airships and vertibirds are anyone's it's the Institute, could be the BoS, but, Boston seems a bit out of their reach, and if the MWBoS had a presence on the East Coast they'd have come into contact with the CWBoS by now (depending on how far after FO3 FO4 takes place).

So, really, I don't think any of the "real" BoS chapters have military branches on the level of a Navy or Airforce.

I suppose it is possible that it is the MWBoS, but without knowing the canon ending of Tactics, we really don't know what that means.

Destroyed Calculator or Good Karma ending means a possibility of peaceful interactions.

Barnaky or Bad Karma ending would pretty much make the MWBoS another Enclave.