[quote=Pepperm1nts]
Machines-guns for anti-air purposes could work. Aside from that, I think only bombs would be feasible. That's a painting of a German airship diving over Warsaw to drop bombs down on the city.
[/quote]
That's the sort of airship I imagined when I thought 'WWI,' although I guess Kilo advocates for ships more comparable to naval vessels like [url=http://th04.deviantart.net/fs70/PRE/i/2014/136/6/1/alkirian_sky_kingdom_battleship__assault__by_lionel23-d7in3y8.jpg]this[/url].