Leviathan Hunter Flying Boat

What would an aircraft built to fight sea leviathans look like?

Obviously, it must have super long range to patrol over the sea for weeks or even months straight, without needing to refuel. So I gave it an unrealistically large fuselage, housing a ridiculous amount of fuel, supplies and weapons. It's the size of a small town.

I chose contra-rotating propellers instead of jet engines for the propulsion, as I believe it might need to fly at low speeds to circle above suspicious water, where propellers tend to have better low-speed fuel efficiency. The lower top speed shouldn't be a big worry: the plane should be way faster than any ship already!

If you're interested in a custom illustration, commission me.