Submarines have been a serious threat to shipping since the Great War. Recently, the Russians are putting subs to sea like they did in the Cold War, ready to menace the shipping lanes once more. And submarines are more deadly then ever, with modern torpedoes like the Mk. 48 ADCAP having a range of upwards of twenty seven nautical miles. By detonating under the keel, they can split many ships in half. And, unlike antiship missiles, there aren’t many good ways to deal with torpedoes. You’re basically limited to a few decoy systems. So what’s a surface ship to do? Why, attack the sub, of course. This usually involves helicopters that can drop sonobuoys and dip sonars. They can also drop torpedoes if they find a sub.

What if the surface ship needs to engage a submarine directly? Suppose the helicopter isn’t nearby, or is out of torpedoes, or the surface ship detected the sub with her own sensors? Modern lightweight (read: anti-submarine) torpedoes have a range of anywhere from about five to about twelve nautical miles, depending on what speed setting they’re using. That’s a bit less than half of what the submarine’s torpedoes can do, giving him the shot long before you have it. What other options do we have for engaging?

We could use a rocket to get the torpedo closer before we drop it. If you have Mark 41 VLS cells, you could use the RUM-139 VL-ASROC, which puts a Mk. 46 torpedo about fifteen nautical miles from the launching ship. There are versions available with the more recent Mk. 54 lightweight torpedo, which has a much better seeker. Depending on speed settings, this gives us very nearly the range that the opposing sub has with his torpedo. Detente.

For those of you who’ve forgotten your high school French, or you uncultured swine who never had any, detente is a French word that means “you both get to die”. Yay. Personally, I’d rather not die, and would love to have the range for the first shot given a good sonobuoy contact and no torpedo-equipped helicopters nearby. For this, we come to another casualty of dwindling budgets in the ’90s, the RUM-125B Sea Lance.¹

The Sea Lance has a bigger motor and a better inertial navigation system. It still fits in a regular Mk. 41 VLS cell. The RUM-125B was originally specced around the Mark 50 lightweight torpedo, but an enterprising designer could fit most any NATO lightweight torpedo in, since they’re all about the same size. The RUM-125B had a range of thirty five nautical miles, so if you see him first, you can shoot him first, helicopters or no. With a powerful weapon like this, it makes the surface ship a more active participant in the search for subs, rather than just a mothership to provide fuel.

But wait, there’s more. You may be wondering why the designation started with B. It didn’t. B is just the normal, conventional-warhead
model. Throw a torpedo, have it engage. When you really, really want range, when Ivan’s sub just absolutely, positively has got
to die, and when you want to really piss off greenpeace, there’s the RUM-125A. This missile variant can lob a 200 kiloton nuclear depth bomb out to a range of one hundred nautical miles. So you’re probably going to be safe from that blast. Maybe. It’s not very accurate, but then, it doesn’t have to be. This is the mother of all depth charges. Guaranteed to crush hulls, kill marine life, and cause an international incident, or your money back!

That’s not all. There were variants (designated UUM-125A and UUM-125B) that could be launched from submarines. These would get launched from the torpedo tubes in a buoyant capsule that would float to the surface and then launch the missile. It’s a great way to give attack subs a long range punch if they’re aware of a sub threat. Or just want to nuke the whales.

So go ahead, Captain Viktor Tupolev. Push your pissant Alfa-class boat as hard as you want. You’ll only die overheated.

Now, if only Sea Lance would work on those pesky land whales on Twitter.

Verdict: Approved by the Borgundy War Department Procurement Board

1.) Yes, this is a lower designation number. Trust me, it’s more advanced. Or don’t. More for me.
2.) This post is all in nautical miles, because we’re talking about things at sea. If you’re a communist, and prefer metric units, multiply all range figures above by 1.85.