Tekken At Sea: Japanese Destroyer vs. Chinese Frigate

Chinese Jiangwei-II class frigate.

Last week a Chinese Jiangwei-II (Type 053H3) class frigate locked its fire control radar on a Japanese destroyer. The name of the Chinese frigate was not mentioned, but the Japanese destroyer involved in the incident was JS Yudachi (DD-103), of the Murasame class. After being lit up by the Chinese radar, Yudachi took evasive action.

The incident begs the question: if the ships had come to blows, who would have won?

Let’s assume a hypothetical fight between the two ships. Now, lacking performance details and other information (engagement range, weather, training, etc.) we’re going to make a lot of assumptions here. You may not agree with some of them. I won’t agree with some of them. Aside from the basic facts, this is more entertainment than anything else.

Setup Since the Chinese frigate locked radar, let’s assume the Jiangwei-II shoots first. Let’s also assume that the engagement took place at 20 kilometers, instead of the 3 kilometers that the fire control incident took place at. We’re assuming this because at 3 kilometers the systems of both ships — particularly the 053H3 — would not be fully useful. In fact, the minimum range for Jiangwei-II‘s anti-ship missiles is 15 kilometers.

Japanese Murasame-class destroyer.

Here we have to make the observation that, while the Japanese and Chinese ships and missiles were developed at roughly the same time, technology, and quality control at the time (late 1980s) were certainly not the same. Against the Chinese baseline, the Japanese systems produced during the same time period are just going to be better. That’s not bias, just reality. Ships from both sides build from 2005 onward would be much more evenly matched.

Round One: Opening Shots The Jiangwei-II frigates carry eight YJ-82 anti-ship missiles, which are comparable to the French Exocet anti-ship missiles in dimensions, range, performance, and warhead. (Hmm…) Exocets have scored hits on two ships, HMS Sheffield and USS Stark. The former, at 4,800 tons was disabled, although there is some debate as to whether or not the warhead detonated. The latter, at 4,100 tons, was hit with two Exocets, one of which detonated. At 4,500 tons Yudachi is in-between both ships. It’s clear that, were a single YJ-82 to score a hit, Yudachi could be in trouble.

Jiangwei-II class frigate firing HJ-82 anti-ship missiles.

In our scenario, Jiangwei-II fires a volley of 8 YJ-82 missiles at 20 kilometers. Traveling at Mach .09, they will reach Yudachi in 65 seconds. Assuming the missiles are fired four seconds apart (a guess) the first missile will arrive in 65 seconds, and the last in 97 seconds.

Yudachi, having detected the lock-on of the missile’s fire control radar, is on alert. The ship is equipped with 16 Evolved Sea Sparrow air defense missiles. It fires 8 ESSM, firing the last at ESSM’s minimum range of 1.7 kilometers, or 7 seconds before the impact of the first Chinese missile. (We’re simplifying here–theoretically, if it destroys the first inbound missiles, Yudachi could fire more missiles uninterrupted.)

At the same time, Yudachi turns to broadside the Chinese ship, allowing her two Phalanx CIWS to engage the incoming missiles. Each Phalanx CIWS will have twelve seconds to shoot down any missiles, from maximum range to impact. No pressure or anything!  In addition to active defenses, Yudachi will be turning on missile jammers and creating clouds of missile-confusing chaff.

Shipboard chaff rocket firing.

The question is: how many missiles get shot down? I just don’t know enough, my Harpoon days are far, far behind me. If I had to hazard a guess, I’d say that maybe one missile gets through. Let’s make some educated, bad guesses.

• Guess #1: YJ-82 Missiles have a 75% success rate (success = missile works, and missile hits target). One missile fails. 7 missiles in the air.
• Guess #2: ESSM volley #1 (20 seconds, 4 missiles, 50% probability of kill) takes out 2 missiles. 5 missiles in the air.
• Guess #3: ESSM volley #2 (20 seconds, 4 missiles, 50% probability of kill) takes out 2 missiles. 3 missiles in the air.
• Guess #4: Phalanx CIWS guns each take out 1 missile. 1 missile in the air.
• Guess #5: Electronic countermeasures and chaff have a 50% chance of diverting a missile.

So, in my wild estimation, there’s a 50% chance of one missile hitting Yudachi. The actual chance may be much better, or it may be much worse. As for the damage, it could be extensive, but being a newer design than Sheffield and Stark, the Murasame class should be able to absorb missile a little damage better. Fortunately, as a humble blogger, I can make bad, entertaining guesses and no one will fire me.

Round Two Now it’s time for Yudachi to shoot back. There’s a 50% chance it’s been hit, so let’s assume that it’s lost half of its combat systems. It now only has three SSM-1B anti-ship missiles. It is still at roughly the same range of 20 kilometers, and the SSM-1Bs can close the gap to the Chinese frigate in sixty seconds.

HQ-7

Jiangwei-II is not as well defended as its Japanese opponent. The frigate fields 8 HQ-7 air defense missiles, copies of the French late 1960s-era Crotale. Furthermore, it’s a 24 year old copy, first introduced in 1989. It reportedly only has “limited capability” against sea-skimming missiles, and the SSM-1Bs are going to be coming in at 5-6 meters above the wavetops. (Not as good as Exocet, but not exactly a ballistic trajectory, either.)

Worse, the frigate doesn’t have a modern radar-directed close-in weapons system like Phalanx. Instead it mounts 4 pairs of 37mm anti-aircraft guns that while radar guided, are mounted side by side in the stern. Turning to broadside like the Japanese ship, only two pairs of guns can engage the enemy missiles.

Again, how many of the 4 Japanese anti-ship missiles get shot down? More guesses.

• Guess #1: Missiles have 100% success rate. 3 missiles in the air.
• Guess #2: HQ-7 volley  (40 seconds, 8 missiles, 25% probability of kill) takes out 2 missiles. 2 missiles in the air.
• Guess #3: 2 37mm radar-directed guns, missile jammers, and chaff take out 1 missile. All missiles destroyed.

Stalemate

USS Stark after Exocet hit.

At this point both ships have exhausted their anti-ship missiles. Unless one closes to gun range, it’s over. Yudachi has sustained some damage, but it still functional. If it had just one more missile, it could have penetrated Jiangwei-II‘s defenses.

And it’s a good thing it didn’t. At 270 kilograms, the SSM-1B’s warhead is more than 50% bigger than the YJ-82/Exocet’s. At 2,200 tons, the Chinese frigate is less than half the size of HMS Sheffield. To repeat, HMS Sheffield was disabled by a single Exocet. If we accept that Yudachi was half-disabled, Jiangwei-II would have been fully disabled by one hit.

How realistic is this? I don’t think any of my assumptions are particularly outlandish, but then again, that’s just me. HQ-7 may be useless against the SSM-1B — “limited capability” is often  marketing-speak for “worthless”. Frankly, I think ESSM is a more capable missile than I modeled. Twelve seconds is probably enough time for a Phalanx CIWS to engage multiple targets. These are the key assumptions, because if Yudachi’s defenses could have shot down just one more missile, it would have shot back with it’s full complement of SSM-1Bs and the Chinese frigate would have been doomed. If this bothers you, adjust the effectiveness of ESSM and Phalanx upwards accordingly. Result: no longer a stalemate.

Did this exercise accomplish anything? Well, it’s a fun exercise. But along the way, we’ve (at least partially) educated ourselves about the relatives strengths of both ships, and their weaknesses. I think it’s a fair assumption that Yudachi would likely survive whether it fired first or not . Jiangwei-II, on the other hand, probably needs to shoot first.

OK, fantasy time over. Back to our irregularly-scheduled posts.

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A contributor and editor at the blog War Is Boring, Kyle Mizokami started Japan Security Watch in 2010 to further understand Japan's defenses and security policy.
Kyle Mizokami has 530 post(s) on Japan Security Watch