Advice mostly for me given by someone else concerning airships · 11:16am Feb 27th, 2019
We've seen several airships with propellers for power, and that includes the Storm King's airships. We've also seen some Equestrian designs that have no propellers, but have fins, instead (More fish-like, perhaps?).
I don't think we've seen any armaments on an Equestrian airship, and I think the only weapon we saw on the Storm King's ships was the harpoon gun--which from the flash and bang, appears to be a proper cannon.
If you were wanting to arm airships, you've got quite the selection. The classic torsion-arm catapults should be just fine, at least on Equestrian ships, as there's a huge gap between the upper deck and the envelope (They were used occasionally in real naval ships, too). Ballistas are generally better, at least for hitting, though they likely don't pack as much of a punch. Really, you want cannons. And of course, you've got all the possible magical weapons you can make.
One thing to keep in mind is that, while the usual ship armaments in our history were for fighting other ships, that might not be the case here. In most periods of history, ships were huge investments, and you really wanted to capture them instead of sinking them if at all possible. Prior to cannons, most of the action was done through ramming, archery, and especially boarding. An Equestrian military will have about a third of its force naturally air-mobile, so you might end up with very different priorities in ships. An Equestrian millitary airship might resemble an aircraft carrier more than a ship of the line, with plenty of space for pegasi warriors, and possibly light weapons intended to help fight other flying soldiers more than ships themselves. Or they might be like flying tanks, small but heavily protected to give the pegasi some armored support against other fliers, or like a flying IFV, an armored vehicle to deliver troops safely onto a defended enemy ship. Then again, you might also see airships much like our naval ships, so unicorn and earth ponies can join in the fight against enemy airships. Lots of possibilities.
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