Hangor-Class vs Kalvari-Class: How Do Pakistan’s and India’s Newest Submarines Compare?

The Pakistani navy few months ago commissioned its first ship, PNS Hangor, a Hangor-class submarine, in China on 30 April 2026, and it arrived in Karachi on 11 June. Developed with Chinese assistance, these submarines will be the newest induction into the Pakistan Navy in recent decades. Recently, in September 2026, it conducted a publicly announced anti-ship cruise-missile firing in the North Arabian Sea.

In this article, we’ll compare the two classes in terms of propulsion, weapons, stealth, and underwater endurance. More importantly, will the new subs make any difference to the Pakistan Navy’s underwater capability, and could they also provide Pakistan with a credible second-strike capability that Pakistan currently lacks?

Pakistan’s Hangor-class submarine programme

Pakistan signed a deal with China in 2015 for eight new submarines under a programme valued at approximately $4–5 billion in contemporary reporting. The agreement includes technology transfer and construction between Chinese and Pakistani shipyards.

The submarines are an export variant of China’s S26 design, derived from the Type 039A/B Yuan-class family operated by the People’s Liberation Army Navy. They are conventional diesel-electric attack submarines.

Under the programme, Wuchang Shipbuilding in China is building four submarines, while the remaining four are allocated to Karachi Shipyard & Engineering Works (KSEW) in Pakistan. The programme has faced some delays. Initially, Pakistan wanted German MTU 396 diesel engines, which were much quieter, but Germany refused, and Pakistan was forced to fit Chinese CHD620 engines.

Names and current status of the eight Hangor-class submarines

India’s Kalvari-class submarine programme

India Navy under Project 75 got six Scorpène-design submarines developed with French assistance. MDL built the submarines with technology transfer and technical support from Naval Group, the French shipbuilder. Talks of inducting three additional Scorpène submarines are in advance stages.

The six commissioned submarines are:

Hangor-class vs Kalvari-class: Technical comparison

The Hangor-class is a larger submarine. Its commonly reported displacement of around 2,800 tonnes exceeds the Kalvari-class’s published submerged displacement of around 1,775 tonnes. It is also approximately 8.5 metres longer.

One of the most important differences is air-independent propulsion. Conventional submarines use diesel engines to generate electricity and recharge their batteries, but these diesel engines require atmospheric oxygen. A submarine must therefore surface or use a snorkel to bring in air while running its diesel engines.

This creates a vulnerability. Even when a submarine is difficult to detect underwater, snorkelling can increase the chances of detection through radar, electro-optical surveillance or other sensors.

AIP reduces the need to do this. It enables a submarine to generate electrical power underwater without relying on atmospheric oxygen for its main diesel engines. This helps sustain low-speed submerged operations for longer periods, although the exact duration depends on the AIP system, available fuel, oxygen supply, and operating conditions.

The Hangor-class is equipped with Stirling-cycle propulsion, based on the Chinese Yuan-class design. India’s Kalvari-class, by contrast, entered service without AIP. This does not mean that the Kalvari-class is incapable of prolonged underwater operations, but compared to Hangor subs, the endurance of Kalvari subs is affected.

However, the Defence Ministry signed a contract in December 2024 for MDL to construct an AIP plug and integrate the DRDO-developed system into Indian submarines. But due to delays, the first Kalvari-class submarine completed its initial maintenance refit without receiving the upgrade.

Submarine Number – Indian Navy Vs Pakistan Navy

Once all eight Hangor-class submarines enter operational service, Pakistan will expand its modern submarine contingent, including its existing conventional submarine fleet includes three Agosta-90B submarines—PNS/M Khalid, PNS/M Saad and PNS/M Hamza—and two older Agosta-70 submarines, PNS/M Hashmat and PNS/M Hurmat, which takes the total number to 13 boats.

India has a more varied submarine inventory. Its conventional fleet includes:

• Six Kalvari-class submarines, the newest fully inducted conventional class.
• Shishumar-class submarines, based on the German Type 209 design.
• Sindhughosh-class submarines, based on the Soviet/Russian Kilo design.

India also possesses strategic 2nd strike capability with its nuclear-powered ballistic-missile submarines (SSBNs), including INS Arihant and INS Arighaat and with two more to come.

Does Hangor improve Pakistan’s deterrence and second-strike capability?

One area where India edges out Pakistan is its second-strike capability provided by SSBNs, which is considered most potent by the nuclear powers, because ballistic missile launch sites and nuclear attack by air assets(primarily by bombers) are relatively easy to detect and give more response time, but finding a submarine armed with a nuclear missile in the vastness of the ocean is like finding a needle in a haystack. Pakistan has tried to improve its ability to deter India across land, air and sea.

Pakistan neither has the capability to build complex machinery like SSBNs nor has the capital; thus, it has been trying to integrate its Babur-3 (also designated as Hatf-VII), a submarine-launched cruise missile (SLCM), into its new subs. Pakistan tested the Babur-3 submarine-launched cruise missile in January 2017. Pakistani officials claimed it as a sea-based weapon with a claimed range of approximately 450 kilometres and the potential to carry different payloads, including a nuclear payload.

But as of now, there is no evidence showing that Babur-3 has been integrated with the Hangor-class, certified for operational launch from it or deployed as an operational submarine-based nuclear weapon.

While the induction of new subs by the Pakistan Navy is a new challenge the Indian Navy has to deal with, on the positive India operates P-8I maritime patrol aircraft and is inducting MH-60R naval helicopters with anti-submarine warfare capabilities. These aircraft and helicopters can contribute to submarine detection, tracking and elimination in conjunction with surface ships and other surveillance assets. The Indian Navy has also been expanding its fleet of domestically built anti-submarine warfare shallow-water craft, including the Mahe-class.