It's just as its name suggests – a vehicle with a mounted tank gun that can travel across water, and it's a concept that probably makes a lot of sense but has never really seen anything remotely close to mainstream popularity. But after years of development, the new Antasena Tank Boat has now begun offshore trials off the coast of Banyuwangi, East Java, just opposite of the island of Bali, and will look likely to become a new staple of the country's defense system that is responsible for defending thousands of individuals islands. Seeing as its a pretty new machine, the Indonesian Ministry of Defense has so far purchased one Tank Boat from defense contractor PT Lundin, but will opt to purchase quite a lot more should they be impressed by its capabilities.