KSEW will produce 4 ‘next-generation’ AIP-equipped submarines
January 26, 2022
The Type-039/041 "Yuan" class conventional submarine, likely the basis for the export-centric S20. Photo credit: Wikipedia

KSEW will produce 4 ‘next-generation’ AIP-equipped submarines


During the handing over ceremony of two landing craft mechanized (LCM) amphibious landing ships, Rear Admiral Syed Imdad Imam Jafri (the Commander of Logistics in the Pakistan Navy) congratulated Karachi Shipyard & Engineering Works Ltd. (KSEW) for winning a contract to produce four “new generation” air-independent propulsion (AIP) equipped submarines (for reference: AIP enables a conventional submarine to operate underwater without snorkeling for oxygen for a relatively long period – potentially weeks).

Although the gradual and incremental progression of Pakistan’s amphibious capabilities is good news, the open recognition that KSEW will construct four new submarines seems to suggest that the landmark deal for eight submarines from China has been inked. Under the agreement, KSEW was to produce four of the eight submarines.

In the aftermath of the Pakistan Navy (PN) walking away from a purchase of three Type 214 submarines from ThyssenKrupp Marine Systems (TKMS) in Germany, the PN initiated talks with China Shipbuilding & Offshore International Co. Ltd (CSOC) for six AIP-equipped submarines in 2011. In April 2015, the Pakistani government approved the purchase of eight submarines from China, and the contract was submitted to Beijing for final approval in July of that year.

While the base design of Pakistan’s forthcoming submarines is widely believed to be a variation of the CSOC S20, the export variant of the Type 039A/041 Yuan-class diesel electric submarine (SSK), it was not clear if the PN had also ordered AIP systems. The S20 is not offered with AIP by default, CSOC requires the customer to acquire AIP systems separately.

Rear Admiral Jafri’s statements clearly confirm that Pakistan’s submarines will be equipped with AIP, but the origin and type were not disclosed. China developed a Stirling-based system, but fuel-cell powered solutions are also (or at least were) under development at the Dalian Institute of Chemical Physics. It will be interesting to see which route the PN chooses, and whether a portion of the submarine deal would go towards supporting the development of a Chinese fuel-cell AIP solution.

Armaments have not been disclosed either. At the minimum, it is very likely that the submarines will be armed with at least six 533mm torpedo tubes to launch heavyweight torpedoes and anti-ship missiles (AShM). In terms of the latter, the PN could opt for the newly revealed CM-708UNB sub-launched AShM. The CM-708UNB has a marketed range of up to 290km.

Pakistan may also try to align the new submarines into its goal to develop an assured second-strike nuclear deterrence capability. The torpedo tubes onboard these submarines may be designed such that they could take on the Babur land attack cruise missile (LACM), which in turn would house a miniaturized plutonium warhead. This is a guess on our part, as with much of this submarine deal, the details have not entirely been confirmed. It will also be interesting to see how the PN equips the submarines’ internals, especially in terms of the on-board electronics as well as command and control systems. In any case, it seems specific details are finally beginning to trickle down, we will keep an eye on how this program develops.