Oh hey, I’m not quite dead yet.
I tend to keep abreast of military development programs, procurement and whatnot, and I’ve written about the topic before. Not so much out of the sort of… milspec fetishism that tends to dominate the topic, but because I find the logistical side of things particularly interesting; which programs reach completion, which are killed too early or too late, which wind up making it into service even when they should never have been built in the first place, and so on.
So the topic of the Navy’s railgun program is a fun one for me, not so much because of the fact that the weapon itself has been languishing in development hell for over a decade, with hundreds of millions of dollars in sunk costs already, but because there’s a small faction of the aforementioned milspec fetishists mingled with alarmist nationalists that is absolutely freaking out over the prospect that China is going to field their railgun first.
And they probably will.
But that’s okay.
For a variety of reasons.
First off, while some folks are claiming that the weapon is fully functional, with a performance profile not dissimilar to the one desired by the US Navy, let’s all be honest about the fact that China isn’t exactly renowned for its honest and forthcoming nature, particularly regarding the capability of its weapon systems in relation to the rest of the world. So it’s possible that the weapon itself is a bit of a paper tiger; I suspect it’s not by accident that the first sea trials of the weapon are being conducted on a landing ship, which is to say, a big empty box that you can pack full of components with fairly minimal effort and with no visible external modifications save for the weapon turret itself. If the Navy wanted to slap its current railgun into a turret and strap it to a floating box with engines, it could probably manage the task with relatively little difficulty.
That doesn’t mean that the system is actually combat ready.
Which brings us to the second reason: maturity. Conducting sea trials is all well and good, and is a step towards achieving that goal, but one of the primary difficulties the Navy’s railgun program has been facing has nothing to do with “making a metal rod go really fast”, and a great deal to do with “making a metal rod go very fast cost effectively on a long term.” Weapon systems are expected to have a fairly predictable lifespan, albeit ones requiring regular maintenance, but if your goal is to have a weapon that does the same job for less money (one of the goals of the railgun program, since an inert metal rod in theory costs less than an artillery shell packed full of explosives), and you wind up with a more expensive weapon (functionally inevitable given the relative maturities of the technologies in question) that fires cheaper ammo, but needs to be replaced three times as often… Then some serious math needs to be done as to whether said weapon is worth investing in at all. And that leaves out little things like “how vulnerable is the weapon system to damage”, or “how quickly can the weapon in question fire”, or most importantly in the case of the naval railgun concept, “is what this weapon offers fundamentally better than the existing alternative?”
Which segues nicely into the third reason: utility. On the surface (punintended), the railgun looks great. 125 mile range, Mach 7 projectile speeds, all with ammunition that won’t explode if the magazine gets hit and “only” costs a few tens of thousands of dollars per round? What’s not to like?
Frankly, there’s a big issue for the US Navy when it comes to railguns: it only has a single class of vessel capable of actually mounting such a weapon. In order to match existing naval gun capabilities in terms of such things as rate of fire, a warship needs to generate a lot of electricity, and while the Zumwalt-class ships were indeed designed with that possibility in mind, it’s important to note that the Zumwalts are currently sailing around with a pair of 155mm cannons they can’t use because in the classic inverse sunk-costs fallacy, after the Navy slashed the production number of the vessels from 32 to just three, the program that was developing the ammunition for those unique cannons was scrapped since the total cost-per-round was approaching $1 million each once development costs and projected production run were factored in. Which is not to say that having them cost $100,000 each would have been particularly thrifty, but it would be fairly typical for the sort of highly-advanced guided projectiles that these weapons were intended to fire, and in theory the Navy could have at least produced a relatively conventional round for a fraction of the cost.
And I don’t consider that a digression, because it illustrates just how incredibly stupid the world of military systems procurement can be.
So with only three ships in the entire navy having the excess power generation to simply drop-in such a railgun, and having a surface fleet in excess of 80 ships mounting existing 5″ guns that can’t simply have a railgun slapped onto them… where would your money be better spent?
Because having a gun that can drop a shot 125 miles downrange with a flight time of less than 90 seconds is great, but only if that round can a.) hit its target, and b.) actually hurt its target when it does. And so far the railgun has yet to demonstrate the ability to do either.
Yes, very fast, meaning that you don’t have to factor in the maneuverings of the target nearly as much when dealing with long range gun duels while sailing the seven seas. Except that nobody has really done that since the Second World War, and for good reason; aircraft and missiles can reach out with precision well beyond the reach of even the most advanced artillery systems, and even when such duels were the order of the day, it required quite a few rounds fired to score even a single hit. After all, both the gun and its target are moving (in three dimensions, even, to a limited extent), and knowing where your target is now doesn’t mean much when the round isn’t going to impact for another minute and a half.
So you don’t just need a railgun, you need guided ammunition for your railgun, assuming you want it to hit anything, and suddenly the cost benefit of firing inert metal rods just went flying out the window at approximately 1.6 miles per second. Because developing guided rounds for conventional artillery was difficult enough; managing it for railgun ammunition, which has a lower internal volume and is subject to an environment that is, shall we say, grotesquely inhospitable to electronics in general, is somewhat more of a challenge. While General Atomics claims they’ve managed to produce electronics that survived the trip, its important to note that those electronics were basically just accelerometers; a long way short of an actual guided weapon.
So oddly enough, making long-range guided munitions is actually significantly easier to do when working with the Navy’s existing fleet of 5″ naval guns, and given that said rounds can carry an appreciable amount of explosives along for the ride…
If all you want the railgun to do is fire cheap ammunition at a single target requiring direct hits in order to be effective, you have a very large, very expensive gun that may never actually be fired except in a defensive role in an attempt to intercept incoming missiles or aircraft. If you want more than that, you have a very large, very expensive weapon that fires very expensive ammunition that still lacks the versatility of a conventional cannon shell. If you want to match the capability of a 5″ naval gun in terms of area bombardment… then in all likelihood you won’t much exceed the capabilities of said 5″ gun in that role.
In point of fact, you might not even match them. Particularly not when viewed in the long term. The current desired rate of fire for the US Navy’s railgun program is supposedly ten rounds per minute; the existing 5″ guns on US vessels already at twice that rate. The barrel life of the Navy’s railgun is supposedly approaching 1000 rounds fired, with a long-term goal of 3000 rounds; the barrel life of the Navy’s 5″ guns is already in excess of eight thousand rounds.
And while you could make the argument that the railgun would be a safer weapon in the event of an actual battle, since its ammunition doesn’t involve conventional explosives or propellants… Remember how Samsung had a bit of a problem with their phones a little while back, something about spontaneous combustion and some pretty energetic fires?
Well, the battery on your average smartphone rarely exceeds 3000mAh, or milliamp-hours, and while converting from one unit of electrical measurement to another is a huge pain in the ass since it requires specific variables like voltage, suffice to say that there will be some pretty serious consequences when you punch a hole in the kind of capacitor necessary to feed a 32 megajoule railgun.