How do you destroy a submarine?

Answer 1

If we're speaking to the proposition of defeating a modern military submarine, explosives are the answer. The idea is to create a blast at a point close enough to the submarine (called a boat by most who sail on them) to damage the pressure hull and cause it to fail. We have observed several approaches across the last few decades.

The challenge has always been to detect the submarine and locate its position with a high enough degree of accuracy to drop a depth charge on it. A type of "saturation" depth charge attack might destroy a boat if the general area is defined sufficiently. We've probably all seen footage of a ship "rolling depth charges" off the stern and launching them outboard via a "gun" of sorts. But times have changed and technology has advanced.

We can use sonar and magnetic anomaly detectors to find submarines, and then use a torpedo to deliver an explosive. The modern torpedo is sometimes sonar equipped, and can be active or passive, or can switch between modes. In the passive mode, it can "listen" for the acoustic signature of the target submarine and home in. It could also "go active" and "ping" to locate a target. Some types of torpedo are wire guided and can be continuously "driven" to a target. These weapons are generally designed to actually impact the target, explode, and defeat it, and can be launched from various platforms (including submarines, of course). Lastly, there are a few powers that have nuclear equiped antisubmarine weapons in their inventory. This weapon only has to "get near" a target to create a shock wave that will defeat the hull of a target submarine, and a nuclear tipped torpedo can be equipped with any of the guidance systems already cited. As you might expect, there are nuclear depth charges as well, but in all cases, locating a submarine remains the major challenge.