This map allows for a side-by-side view of an airship deck as well as a grid for tactical positioning for ship combat.

If you are using this for a naval battle simply change the stage background and the ship room to a blue or water, and edit the ship itself as you see fit.

I use Starfinder's ship combat rules, modified to work reasonably well with D&D 5e and the Eberron setting, as I don't find 5e's ship combat rules very fun.