As previously covered by The Diplomat, Pakistan announced earlier this year that it has agreed to purchase eight modified Type 41 Yuan-class diesel-electric submarines from China. These boats will provide Islamabad with much-needed Anti-Access/Area Denial (A2/AD) capabilities against the Indian Navy in case of war. This would be especially useful in case of an Indian blockade of Pakistan’s coast and could give New Delhi grounds to pause before deploying its planned new aircraft carrier, the INS Vikrant.
A Yuan-class submarine is undoubtedly a great piece of kit. It is China’s first class of submarines to incorporate an indigenously designed- and constructed Air-Independent Propulsion system (AIP), giving it a cruise speed of 18 knots and an operational range of 8,000 nautical miles. Although the export version of the Yuan, named the S-20, does not automatically come fitted with the AIP, Pakistan has apparently been able to secure it for its subs. Furthermore, the Yuan is integrated “with advanced noise reduction techniques including anechoic tiles, passive/active noise reduction and an asymmetrical seven-blade skewed propeller.”
Combined with the AIP, this makes the Yuan-class the quietest non-nuclear sub in the PLAN. Furthermore, the Yuan has an impressive set of teeth. Aside from six tubes firing standard 553mm torpedoes, it is equipped with the YJ-8/8A Anti-Ship Cruise Missile (ASCM). While this weapon only has a maximum range of between 30-42 km, there are plans to equip the Yuans with the YJ-18 ASCM. These missiles have a reported range of 220 km and, represent a real A2/AD “force multiplier” for the Yuan. Whether Pakistan will attempt to acquire these missiles, or opt to go for another option (such as their indigenously produced Hatf VII Babur) is unknown.
The sale raises one crucial question: why is China selling Pakistan these subs? There is undoubtedly a commercial aspect to this transaction (it is unknown how much Pakistan will pay for these boats, although it is certainly in the multi-billion dollar range). However, one potential reason which is worrying analysts in New Delhi is that this represents a step in China’s possible ambitions to have a toehold in the Indian Ocean. Without opening the can of worms that is the “String of Pearls” debate, it’s worth looking at this possibility.
Here are the facts: Firstly, the Indian Ocean is important for China for a range of reasons. The amount of Chinese sea-borne trade which passes through the Indian Ocean sea-lane is staggering. These sea-lines of communication (SLOCs) represent a lifeline for the Chinese economy, not least in terms of imports of natural resources, especially hybrocarbons, and exports, in terms of manufactured goods. Any naval strategist worth his salt has read Alfred Thayer Mahan, and will immediately recognize the importance of securing a trading state’s SLOCs. China is no exception.
Secondly, China has recently deployed submarines to the Indian Ocean. (This, incidentally, included the visit of a Yuan-class boat to Karachi.) According to Beijing, these are primarily there to participate in the ongoing anti-piracy campaign in the Gulf of Aden. While this is at least partially true, it is also likely that they are conducting exercises, surveys, and perhaps even combat patrols which can be useful for future operations in the Indian Ocean. Thirdly, Beijing does care about its image and is “realistic” about its power-projection capabilities. According to a recent US Naval War College report, it’s unlikely that China will construct overseas bases in the same way that the United States or France have in the near future in fear of alarming other stakeholders and overstretching naval resources needed closer to home. Finally, China is a long way from the Indian Ocean, and Pakistan is its closest partner in the neighborhood.
Even if its subs can stay at sea for months without refueling at a time, its crews can’t. Having a well-fitted anchorage close to a submarine’s intended area of operations makes it much easier to rotate crews, take on fresh supplies, and carry out maintenance. The PLAN has already called on ports in Oman, Djibouti, and Aden during its anti-piracy campaigns in the Gulf of Aden. However, this has so far only included surface vessels. Submarines often require more specialized facilities to function effectively. Locating a resupply place (not base) in the friendliest state in the area makes sense.
A Pakistani naval facility which already berths compatible subs sounds like a good fit for such a “place.” It would remove the need to permanently station a large number of personnel and equipment abroad, while providing adequate maintenance facilities for the sort of routine repairs that submarines unavoidably need in order to function smoothly over long periods of time. This wouldn’t represent the first time this kind of arrangement has occurred. For example, the British Oberon-class was used by several other allied states during the Cold War, including Australia and Canada. The fact that these navies operated the same class of vessels facilitated maintenance during exercises and visits.