Indo-Pacific submarine proliferation affects safety

The Indo-Pacific will be a focal point of submarine proliferation in coming years, with an estimated 250 boats expected to be operating in the region by 2030.

This proliferation currently takes place both horizontally – referring to existing fleets expanding their capabilities – and vertically, i.e. the entry of new submarine operators.

A diverse array of factors is fuelling this phenomenon, including threat perceptions. However, also enabling this proliferation has been the emergence of second-tier submarine vendors that provide an alternative, cost-effective source for cash-strapped regional navies seeking an underwater arm.

For example, the Indonesian Navy decided to acquire modified Type 209/1400 Chang Bogo-class diesel-electric submarines from South Korea. The Royal Thai Navy selected the S26T (export variant of the Chinese Type 039A/B Yuan class) to kick-start its submarine capability that it lost in the 1950s.

China also does brisk businesses in the Indian Ocean, with Bangladesh acquiring a pair of second-hand Type 035G Ming-class boats, and Pakistan purchasing eight new-build S26 variants to revitalise its ageing French-built fleet.

Generally, new submarines entering service in Indo-Pacific navies could be characterised as being larger sized. For most navies the bracket used to be a 1,500-2,000t submerged displacement but, currently and in the future, the bracket will creep to 3,000t or more.

Larger boats confer technical, tactical, operational and strategic advantages. They possess greater room for fuel and battery capacity, a bigger and potentially more varied weapon loadout and sensor suite, plus better crew habitability that certainly facilitates sustained operations.

A larger submarine also offers ample redundancy for subsequent retrofits of new systems to raise overall capability, and these add-ons include vertical launch systems, a special combat swimmer exfiltration/infiltration lockout chamber and hatch, plus air-independent or fuel-cell propulsion.

More importantly, from the lifecycle standpoint, given that acquiring, operating and maintaining a sustainable underwater fleet is exorbitantly expensive, a larger boat that carries the potential for midlife upgrades can remain in service longer. This helps ease the fiscal burden to a certain extent.

However, the end result is that the modern, contemporary submarine that roams Indo-Pacific waters is increasingly lethal – both by virtue of prolonged underwater endurance, range, long-range striking power and, most importantly of all, stealth. These boats, assuming that all 250 come on line by 2030 as projected, present significant challenges to both maritime safety and security.

Two types of scenario are projected here. The first envisages an incident involving encounters between submarines, and the other between a submarine and other anti-submarine forces. 

'Two types of scenario are projected here. The first envisages an incident involving encounters between submarines, and the other between a submarine and other anti-submarine forces.'

— The Geobukseon

The latter aspect is one often overlooked, as the focus is primarily on the underwater vessel itself. One ought not to forget that Indo-Pacific navies are also bolstering anti-submarine capabilities, including underwater hydrophone arrays for passive detection, helicopters and long-range maritime patrol aircraft.

This first scenario is one that assumes multiple types of forces operate within a relatively tight maritime space, spanning the aerial, surface and subsurface columns. The likelihood of encounters is high, and it can be safely assumed that this underwater ‘cat and mouse’ game is going on right now.

Submarines and anti-submarine forces track one another in a quest to gather valuable peacetime intelligence that could aid in contingency planning. It is also conceivable that some submarines are operating close to foreign shores.

Two types of mishaps could happen under this scenario. The first is an encounter that degenerates into a diplomatic spat, like the ‘Whiskey on the Rocks’ incident when a Russian submarine ran aground near a Swedish naval base in 1981. Such an incident is not inconceivable regionally given the sinking of the ROKS Cheonan and a recent foray of a Chinese nuclear-powered submarine near the Senkaku/Diaoyu Islands.

The other type of mishap would be an accident that ensues from close encounters, such as a collision between submarines or with surface forces. Such a collision could be potentially fatal, with the possible loss of a boat with all hands.

The second scenario relates to operational accidents. The Indo-Pacific is not devoid of such past episodes, for instance the loss of the Indian submarine Sindhurakshak in 2013. Additionally, the American submarine Greenville capsized a Japanese trawler in 2001 when performing an emergency surfacing drill.

The most recent submarine tragedy was when the Argentine submarine San Juan went missing, reportedly due to an internal explosion sparked by onboard technical glitches. There are, of course, other accidents that have fortunately resulted in no or minimal casualties.

However, no chances ought to be taken.

In the Indo-Pacific, while submarine proliferation goes on, underwater operational safety measures continue to lag. The region does have existing mechanisms for cooperation in this field, such as the Asia-Pacific Submarine Conference (APSC) and Exercise Pacific Reach (XPR), all convened since the early 2000s. A newer addition is the Submarine Operational Safety Conference (SMOSC).

However, APSC is mainly a dialogue platform for confidence-building. SMOSC and XPR truly focus on promoting submarine operational safety but they are largely dominated by a handful of key submarine operators who happen to have the capabilities, political will and enthusiasm.

Moreover, while regional navies are eagerly snapping up submarines, most have relegated submarine emergency response (SMER) capabilities to an afterthought, one largely seen as a costly expense. 

SMER capabilities are not evenly distributed in the Indo-Pacific – East Asian navies such as those of China, Japan and South Korea tend to possess the most comprehensive suite of assets comprising rescue ships replete with a deep-submergence rescue vessel or diving bell, decompression chambers and other underwater medicine facilities.

This is not the case in Southeast Asia, where only Malaysia and Singapore have dedicated SMER assets. To compensate, Indonesia and Vietnam, for instance, inked bilateral submarine rescue pacts with Singapore. However, with six Kilo-class submarines, even Hanoi is now seriously considering its own SMER capabilities.

The situation is more dismal in the Indian Ocean. Despite being a long-time submarine operator, the Indian Navy has found itself hamstrung by a lack of adequate SMER capabilities, well exemplified in the Sindhurakshak loss. It is only belatedly implementing measures to rectify this gap.

Bangladesh and Pakistan do not appear to have any capabilities or plans to procure SMER assets, most likely due to funding constraints. As the San Juan incident showed, navies without this emergency capability have to rely on foreign assistance. When an underwater mishap takes place, time becomes the essence in the race to locate the submarine in distress and rescue surviving crew.

However, getting foreign SMER capabilities takes time – from mobilisation to cross-country transport and then deployment to site – and it may run into diplomatic and other technical hurdles.

Think of the Kursk incident in 2000, for example, where Moscow vacillated on foreign SMER offers. By then, it was too late. Trapped submariners usually have barely more than 48 hours to survive before asphyxiation sets in.

'Trapped submariners usually have barely more than 48 hours to survive before asphyxiation sets in.'

— The Geobukseon

If active mitigation measures are hampered by a lack of and uneven distribution of SMER capabilities, something likely to persist for the foreseeable future, then an alternative would be passive or preventive measures. In that case, water-space management (WSM) and prevention of mutual interference (PMI) instruments could forestall mishaps arising from close encounters.

However, there is thus far no such mechanism in the Indo-Pacific, unlike in NATO. There have been some new initiatives. For example, the Royal Malaysian Navy lately introduced Malaysian Submarine Exercise Areas (MSEA), comprising three parcels of properly delineated maritime space – two off East Malaysia and one off eastern Peninsular Malaysia in the South China Sea.

However, not all neighbours took this initiative kindly, some plausibly viewing the MSEAs as a possible Malaysian attempt to restrict freedom of navigation to foreign vessels.

Singapore has been proactively pushing for passive/preventive measures – first proposing an underwater code for unplanned encounters at sea (CUES), spawned from the original CUES promulgated in April 2014 and signed onto by 21 navies.

The underwater CUES idea has floated around for years but thus far has found no takers. It essentially envisages a set of standard WSM/PMI procedures that individual submarine crews can implement while under way, but the concept has been widely (mis)interpreted as one that obliges the signatory to reveal its submarines’ whereabouts.

So far, the Republic of Singapore Navy continues to push for regional adoption of the underwater CUES. In the interim, it unveiled last May the Submarine Safety Information Portal (SSIP), housed under the Information Fusion Centre at Changi Naval Base. Like the underwater CUES, SSIP calls for voluntary, non-binding participation.

SSIP seeks to promote underwater situation awareness through voluntary sharing of information, such as the location of shipwrecks or other navigational hazards, which can be collated, synthesised and fused onto a common operating picture that participating navies use to promote submarine operational safety.

This constitutes a good start, possibly building gradual acceptance and paving a way for the underwater CUES in the future.

Clearly, while existing steps are laudable, they still fall short in pace with the extent of submarine proliferation in the Indo-Pacific. It is time that regional navies seriously consider both passive and active measures to promote submarine operational safety instead of relegating them to an afterthought.