Submarine induction:
Pakistan’s naval power was claimed to be bolstered in mid-August 2025 when China gave Pakistan its third Hangor-class submarine. With their sophisticated sensors and weapons, the Hangor-class submarines would contribute to the maintenance of “regional power equilibrium” and maritime security, according to Pakistan’s Deputy Chief of Naval Staff. A Chinese military affairs expert claims that the Chinese Hangor-class submarine is distinguished by its powerful underwater combat capabilities, which include extensive sensor systems, superior stealth qualities, high mobility, extended endurance, and powerful firepower.
Estimated features:
Type 039B Yuan-class submarines used by the Chinese navy (PLAN) are exported as Hangor-class submarines. The subsystems and particular armament systems haven’t been disclosed by the Pakistan Navy yet. Many experts believe Hangor uses the Stirling AIP system, similar to China Shipbuilding and Offshore International Company’s (CSOC) S26 design. However, Pakistan hasn’t publicly disclosed the propulsion system delivered to it. With a displacement of 2800 tonnes and a length of 76 meters, Pakistan’s submarines will be marginally shorter than the original Chinese S26 design but heavier.
Both Chinese YJ-82 anti-ship missiles and Pakistani 450 km range Babur cruise missiles (SLCM) could be launched from these submarines’ six 533 mm torpedo tubes in the bow. With an ability to attain underwater speeds of up to 20 knots, its AIP will enable it to remain underwater for longer, making it more difficult to detect.
Naval capability enhancements:
It is claimed that Hangor submarines have superior acoustic and stealth capabilities, which make it harder for adversary systems to detect. It might be equipped with anti-ship missiles and torpedoes, enhancing Pakistan’s deterrence capabilities in the Indian Ocean region (IOR). It is being reported that these could greatly improve Pakistan’s area denial and anti-access (A2/AD) capabilities in the IOR. With their 21-inch torpedo tubes, they could launch anti-ship cruise missiles and powerful torpedoes like the Chinese Yu-6.
Although Pakistan hasn’t officially revealed its range, approximations are provided by open-source data based on its Chinese S26 design. The submarine is estimated to have a submerged endurance of 768 nautical miles, or almost 20 days without surfacing. This range is anticipated to be around 2,000 nautical miles when using diesel-electric power and AIP, enabling endurance of up to 65 days at sea. These numbers are supplemented with an operational diving depth of around 300 meters and a stated maximum submerged speed of 17 knots. But German MTU engines that were initially intended but prevented by export constraints are to be replaced by Stirling AIP systems.
Pakistan’s intention to construct a strong second-strike nuclear deterrent at sea is demonstrated by the successful test of the so-called indigenously designed ship-launched ballistic missile (SLBM), which is the SMASH missile. In the meantime, improvements in unmanned maritime technologies are claimed to have improved the Pakistan Navy’s ability to monitor and react quickly to alleged Indian threats.
Prospective technical issues:
In Thailand’s purchase of the S-26T, a Chinese Type 039B submarine derivative, the German government had refused to issue export licenses for its MTU 396 diesel engines, after which the Thai agreement fell through. Similarly, final approval of export clearance hasn’t been announced by Pakistan for its Hangor submarine. It’s also unclear if Pakistan had agreed to China’s alternate plan of Hangor to be powered by a locally produced CHD-620 engine. It’s being assessed that Chinese alternatives could have a detrimental influence on submarines’ operational efficacy, as they’re constructed with poor cast and shaped materials, assembled with inconsistent quality control standards, and after a few hundred hours of operation, require near continuous repair.
Engine performance has a direct impact on speed, endurance, and—most importantly—acoustic signature. A submarine’s ability to remain stealthy may be compromised by any departure from a typical noise profile. India’s P-8I Poseidon planes, MH-60R helicopters, and an expanding fleet of surface combatants with cutting-edge sonars and homegrown torpedoes patrol the northern Arabian Sea, a dense anti-submarine warfare (ASW) environment. Hangor’s ability to survive in these waters could be severely diminished by any decline in its propulsion efficiency, endurance, or quietness. Modern ASW utilizes passive sonar arrays that can capture even faint propeller whines or pump hums at 100–120 decibels.
With China’s practice of keeping advanced systems for internal use, the S26 model intended for Pakistan is probably devoid of critical technologies. Three main areas of sensors, combat management systems (CMS), and acoustic quieting are where Chinese export submarines frequently diverge from their domestic equivalents. It is being assessed that S26’s sensor suites are less capable, which could limit its capacity to identify sophisticated submarines at a distance—a crucial weakness against highly developed ASW networks. CMS is used by modern submarines to combine tactical data, electronic warfare, and sonar into useful targeting options. Interoperability is often hindered by export versions’ reduced CMS and constrained networking capabilities. Hydrodynamic shaping, machinery isolation, and sophisticated hull coatings are essential for submarine stealth. The Hangar probably has less sophisticated acoustic dampening, which makes it more noticeable in the Indian Ocean, where climatic conditions intensify the spread of underwater noise.
Implications for India:
India views China and Pakistan’s maritime cooperation as a long-term danger. But German-designed Type-214 submarines for India have “superior technology” compared to the Hangor class. India will gain a revolutionary capability when fuel-cell-based AIP systems and lithium-ion batteries are combined. While lithium-ion batteries enable submarines to cruise at high speed, fuel-cell AIP provides long-range endurance at low speed. Type-214s can dive deeper thanks to polymer electrolyte membrane (PEM) hydrogen fuel cells. They can stay underwater for up to three weeks thanks to hydrogen-powered fuel cell-based AIP technology. Since an electrochemical reaction generates no sound, fuel cells provide the lowest noise levels, which improves overall stealth. It has a water ram expulsion system that allows it to discharge torpedoes covertly. It has reduced thermal and magnetic signatures to increase stealth and is equipped with torpedo countermeasures such as underwater effector jammers.
By 2028–2030, the projected induction of eight AIP submarines with nuclear-capable cruise missiles will significantly change India’s maritime security landscape. For wide-area submarine surveillance, India uses P-8I Poseidon aircraft. In March 2024, the first squadron of MH-60R Seahawk helicopters equipped with torpedoes and dipping sonar went into service. India launched the first of a new shallow-water ASW vessel, INS Arnala, on June 18, 2025, and patrols coasts with four Kamorta-class corvettes. The multilayer detecting net created by these resources reduces Hangors’ range of motion. Apart from platforms and weaponry, India has made significant investments in maritime domain awareness through intelligence sharing, coastal radar systems, and satellite-based monitoring. India is able to track submarine movements and surface dangers in real time due to initiatives like the Information Fusion Centre.
Conclusion:
It is crucial to note that while AIP increases endurance, it doesn’t eliminate detection of submarines, particularly in noisy, shallow littorals like Karachi and elsewhere where acoustic traces are very detectable. Pakistan’s submarines are hindered by their geographic location. While the acquisition of Hangor-class submarines may increase the quantity of submarines for Pakistan, it’s not likely to increase the quality or underwater warfare capability of Pakistan vis-à-vis India in the near future. Even though India is also steadily progressing to develop its own AIP submarines via Project-76 in the near future, the naval power balance won’t shift drastically towards Pakistan’s even with the acquisition of China’s Hangor-class submarines.
