In WWII, the arrogance of US naval intelligence caused us to not recognize the danger of the Japanese Type 93 torpedo who's range matched that of our naval guns and was undetectable as it did not give off the bubble trail of normal torpedoes.
The Japanese trained naval lookouts for night combat, and were superior to our radar at the time. Able to be lauched from suface vessels or submarines, they arrived without notice, their 1100 lb HE warhead doing devastating damage.
As a result we got our second bloody nose at Guadalcanal. It's legacy, Ironbottom Sound.
Entering the Second World War, the United States dramatically underestimated the effectiveness of certain Japanese naval systems and operations. The tendency to look askance at Japanese naval prowess during the interwar period obviously impacted the failure to anticipate the Pearl Harbor attack. But it is less widely understood that U.S. intelligence similarly underestimated the strength of Japan’s primary naval fighter aircraft (the Zero), the dramatic effectiveness of its long-range torpedoes, as well as its dedication to mastering difficult, but essential operations such as night combat. Remarkably, these problems in assessment occurred despite a plethora of openly available information regarding Japanese naval development during that time.
There are many reasons, of course, that contemporary China’s maritime ascendancy is starkly different from that of Imperial Japan almost a century ago. In particular, there is hardly a shred of evidence (reef reclamation included) to suggest that Beijing is inclined to undertake a rampage of conquest similar to Japan’s effort to bring the whole of the Asia-Pacific to heel from 1931 to 1942. Still, the complex maritime disputes in the Western Pacific require that American strategists keep a close eye on the evolving military balance. In that spirit, this installment of the Dragon Eye series turns once again to focus a bright light on one of the newest elements of China’s missile arsenal: the YJ-18 anti-ship cruise missile (ASCM).
Let us return briefly to what has been revealed about this new missile from both the recent U.S. Office of Naval Intelligence (ONI) report, as well as the annual Pentagon report on Chinese military power. The ONI report is generally well done, but curiously the new YJ-18 only rates a mention in two spare sentences. This report notes that the YJ-18 can be vertically-launched (generally from a surface combatant) or alternatively submarine-launched, but there is no discussion of its supersonic sprint vehicle. Since the U.S. Navy (USN) lacks a supersonic ASCM and will not have one in the foreseeable future, this omission is troubling. Similarly puzzling is the decision not to discuss the recent appearance of another supersonic ASCM, YJ-12, in China’s arsenal. True, such capabilities did exist earlier in other forms, namely as imported Russian systems, but the indigenization (and likely upgrade) of these capabilities is hardly insignificant and will mean they are much more widespread and employed with greater confidence and proficiency.
The 2015 Department of Defense report does offer a bit more detail and thus draws the proper attention to the YJ-18 threat, but again does not mention its supersonic sprint vehicle. The YJ-18 ASCM is described as a “significant step” and subsequently as a “dramatic improvement” over current missiles in China’s inventory. Perhaps most significantly, however, the DoD report puts the range of YJ-18 at 290 nautical miles – more than double that of its likely progenitor, the Russian SS-N-27 Klub ASCM (export version). If correct, moreover, this new range will, in the near term, more or less quadruple the range of the standard ASCM fired from most PLA Navy submarines.
It is projected that YJ-18 would have an initial subsonic phase estimated at .8 Mach similar to the Klub of about 180km, but 20km from the target would unleash the supersonic sprint vehicle at speed of Mach 2.5 to 3. The “dual speed” function allows the system to realize certain advantages of subsonic cruise missiles, such as their “relatively long range, light weight and universality …” but also takes the chief advantage of supersonic ASCMs as well, namely the ability to radically compress the enemy’s reaction time.
The Chinese article relates another advantage of the “dual speed” approach. Just as the missile comes into contact with the ship’s defenses, it “sheds the medium stage …,” thus simultaneously and dramatically altering both its speed and also its radar reflection, “which would impact the fire control calculation.”
It is obviously the ever-growing sophistication of the Chinese ASCM arsenal that poses the “clear and present danger” to American sailors.
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