The US-Japan containment of the passage of Chinese submarines through the West Pacific island chains has seen a new development. According to the Tokyo Shimbun on Jan. 13, the Japan Maritime Self Defense Force (JMSDF) has defined the waters in the triangular area connecting Tokyo, Guam and Taiwan as the “TGT Triangle.” The two countries plan to tighten underwater surveillance within this area, which lies between the first island chain linking Tokyo, Okinawa, Taiwan and the Philippines and the second island chain linking Tokyo, Bonin Islands and Guam.
The tightening of US-Japan underwater surveillance is a result of the growing difficulty in tracing Chinese submarines. According to the research and observations of Hans Kristensen of the Federation of American Scientists, over the past five years, the number of Chinese submarines carrying long-distance cruise missiles has increased more than 30 times, although the US and Japan only have made such information public fewer than five times.
A rough estimate implies that they have failed to precisely monitor more than 70 percent of submarine activities. One piece of information that proves this was a Dec. 31 report in the Sankei Shimbun that the JMSDF had found that a Chinese nuclear-powered submarine had once again broken through the first island chain in February 2009, between Miyako Island and Yonaguni Island, without Japan detecting a clear navigation path.
Also, after North Korea’s small submarine sank the Cheonan, a South Korean warship last year, the US on several occasions sent warships to participate in South Korea’s military drills to strengthen the latter’s anti-submarine capacity. However, some South Korean naval officials have questioned the effectiveness of the US’ high-tech anti-submarine system in shallow waters. The reason for this is that the research and development of the US system doesn’t keep up with the qualitative and quantitative changes in China’s submarines.
China’s third AIP-equipped Yuan-class submarine is so advanced that it is difficult to detect and Beijing is currently developing a next-generation undetectable submarine.
In response, the US and Japan are accelerating their joint development of sensitive sonar systems and anti-submarine tactics. Last year, Japan also decided to increase the number of its submarines from 16 to 22 and to build an aircraft carrier-like destroyer that can carry nine anti-submarine helicopters. In its new five-year defense buildup plan starting this year, it has added one more -helicopter--carrying destroyer and 10 P1 patrol planes.
Looking back at Taiwan’s anti-submarine capacity, the two, almost 70-year-old, Guppy-class submarines almost don’t dive anymore and only function as surface warships to avoid accidents. The two Chienlung (劍龍) class submarines, modeled on the Netherlands’ Zwaardvis-class, have almost reached their 25-year service limit. Furthermore, no structural renewals or system upgrades have been carried out.
In recent years, large numbers of senior submarine officers have retired, causing a lack of personnel and skills. In addition, both ships and submarines employ anti-submarine strategies and tactics that are more than a dozen years old. Today, the two Chienlung-class submarines are Taiwan’s only subs with actual warfare capacity, but since they have to be used for all training tasks, they are being overused and worn down.
During the Navy’s annual Haisha (Shark, 海鯊) exercise in the waters outside Greater Kaohsiung’s Zuoying on Feb. 27 last year, a joint anti--submarine detachment detected an unidentified object underwater at 11am. Planes and warships constantly traced the object until 6pm. Over the next three days, the detachment commander, Naval Fleet Command and Navy Command Headquarters all made inconsistent public announcements on the incident and they were unclear as to whether the object was a submarine. This is another piece of evidence.
The submarines are used to play the role of an imaginary enemy in peacetime to assist the training of troops on surface ships or in the air, but judging from the current quality and quantity of Taiwan’s submarines, they are unable to fulfill this role. Although the 12 P-3C anti--submarine planes purchased from the US will soon arrive, there may be no submarines used in future Haisha drills. How will the Navy go “shark hunting” then?
It was unusual for the JMSDF to include Taiwan in the “TGT Triangle” of strengthened regular underwater surveillance. First, to make up for weaknesses at the end of the first island chain, Japan made the concrete decision to station troops and set up military facilities on Yonaguni Island to strengthen intelligence and anti-submarine surveillance. Second, the deployment implies that Taiwan is the weakest anti-submarine link in the island chain and that the US and Japan would rather remedy that weakness themselves. Taiwan’s overall anti-submarine capacity is likely to be excluded from the US-Japan force as our capacity rapidly declines.
Wang Jyh-perng is an associate research fellow at the Association for Managing Defense and Strategies.
TRANSLATED BY EDDY CHANG
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