Those rectangular plates you see are antigravity emitters. It was thought preferable when the game pitch was being designed to have some way of tracking vehicle health that didn't involve an intrusive UI.
Of all the more literal variations of the flying ship philosophy, this one is undeniably my favourite. I very much appreciate the U-Boat inspiration from the foreword hull, and the way this thing bristles with gunbarrels just makes me grin a bit.
But it seems a bit small for a destroyer, don't you think? This strikes me more as a corvette or sloop sized thing...
It's pretty small for a destroyer, but the thinking from the art director I was working with was that it would seem larger than it was in-game. There's an odd truncation to any elements that aren't critical for play.
The power source is a lightweight fission plant, and the engines are derived from that. It uses some sort of antigravity for lift, which is projected from those plates you see. The art director wanted some way of being able to visually quantify damage to the ship, and those plates are what we went with.
Personally, I'd shift the forward-most turret on the bottom to be embedded into bottom of the bow to cover up a head on blind spot for gun coverage. Aside from that, I very much like the design. It retains enough classic warship design to be recognizable without being absolutely married to the concept.