Das Boom: 6 best weapons designed to kill submarines

China and Russia are both building up their sub fleets, and potential conflict areas in the Black Sea, South China Sea, and under the Arctic Circle mean it's possible submarine warfare could make a comeback. If the NATO and Russian or Chinese fleets clash, these are 6 weapons that will decide who comes out on top:

1. F21 Heavyweight torpedo

The F21 is a relatively new torpedo being fielded by the French Navy. It can swim at speeds of 25-50 knots for an hour while searching for an enemy sub. Since it uses a quiet electric battery to power itself through the water, it allows French subs to fire at the enemy without giving up their own position.

2. Mk. 54 lightweight torpedo

The U.S. and allied navies have one of the best light torpedoes in the world in the Mk. 54. It has a 96-pound warhead guided by a torpedo that can ignore enemy countermeasures and home in on an enemy sub at 40 knots. It can be launched from ships, helicopters, and planes and reaches deep enough to kill all known subs.

3. Improved Shkval underwater missile

The Shkval is a Russian weapon that moves under the surface like a torpedo, but is generally referred to as a missile or rocket because it creates a pocket of air to move through in the water.

This reduces friction and allows it to fly through the water at speeds of over 230 mph. A 463-pound warhead then detonates after a set time, destroying nearby enemy submarines or incoming torpedoes. There's speculation in the West that it would also destroy the submarine that fired it.

4. RUM-139/RUR-5 Anti-submarine rockets

Anti-submarine rockets are fired from a Navy ship into the water where the missile then deploys a torpedo. This allows the torpedo to start chasing the sub from relatively close, reducing enemy reaction time. It also allows ships to fire torpedoes from much greater range than would normally be possible.

Currently, U.S. Navy anti-submarine rockets carry the Mk 54 torpedo described above. Some ships used to carry rockets with the Mk 45 nuclear torpedo described below.

5. Anti-submarine mortar

Anti-submarine mortars and grenades are the shotgun of anti-submarine warfare. A few dozen rounds are fired at once and sink through the water, detonating against the submarine hull with a contact fuse.

They're lethal in short-range fights that could occur in a fjord or sea channel, but their limited range means an enemy submarine would have the advantage in a long-range fight where the sub's missiles and torpedoes could be launched.

6. Mk. 45 and T-5 nuclear torpedoes

During the Cold War, both the U.S. and Russia developed nuclear torpedoes. While they aren't in service today they're still some of the most effective weapons for killing an enemy submarine. They could also kill the firing sub, so they're not great weapons, just effective.

The Russian T-5 in the video above carried a 3.5 kt nuclear warhead. The U.S. Mark 45 had an 11 kt nuclear warhead. Both torpedoes were steered into position and detonated via a command wire between the torpedo and launching submarine.