Quoting Josh Guilbert
I am not a huge fan of hover tank's nor dont understand there purpose but this tank look's beast.The gun looks like it would be a smaller caliber? maybe to hit another tank's weak spot's at long range.
regular tanks get stuck in mud, get blown up by mines, cant cross water, go slowly. A hover tank doesnt have these problems. They hover, or fly above the ground, so they can go places tanks cant. They use downward facing engines like a harrier to hover. The gun is big for even 57 caliber. I would think for scale the gun should be maybe 60 caliber.