On April 30, 2026, the Pakistan Navy formally inducted its first Chinese-made Hangor-class submarine, the PNS/M Hangor, in a high-profile ceremony at Sanya, China, attended by President Asif Ali Zardari and Naval Chief Admiral Naveed Ashraf.
While Pakistani leadership hailed this $5 billion project as a historic step for securing maritime trade and regional balance in the Arabian Sea, the underlying facts point to a complicated scenario.
Despite the strong message of the China-Pakistan alliance, the Hangor initiative looks more like a practical workaround than a true shift in naval dominance.
Since Pakistan has been unable to procure actual nuclear-powered ballistic missile submarines (SSBNs) from its allies, it is testing a highly unorthodox maritime strategy.
The plan involves placing nuclear weapons on standard diesel-electric submarines outfitted with Air-Independent Propulsion (AIP) technology.
Although this mixed approach forces regional navies to rethink their security protocols, experts question whether such a system can survive long enough during a conflict to act as a reliable strategic deterrent.
The core of this new underwater threat is the Babur-3 submarine-launched cruise missile (SLCM).
Initially tested in 2017 using a submerged platform, this missile is Pakistan's bid to complete the naval wing of its nuclear triad.
With an estimated strike range of 450 kilometres and the capacity to carry a nuclear payload, the Babur-3 is claimed to feature high-tech guidance and underwater propulsion systems meant for highly accurate strikes.
The logic behind deploying the Babur-3 is clear. By keeping nuclear-armed missiles hidden at sea, Pakistan hopes to guarantee its ability to strike back even if its land-based weapons are destroyed in an initial attack.
Ideally, a submarine moving silently beneath the waves offers unpredictability and stealth, making it harder for opposing forces to track and thus reinforcing the country's overall deterrence.
Nevertheless, the entire success of this sea-based nuclear strategy relies entirely on whether the submarine carrying the missiles can actually survive an enemy hunt.
As Pakistan's older French-built Agosta-90B submarines near the end of their operational lifespan, the new Hangor-class is set to take over as the main vessel for the nation's sea-based nuclear forces.
Based on the Chinese Type 039B Yuan-class design, these 76-metre-long submarines displace around 2,800 tons.
Out of the eight vessels planned, four are being built in China and four at the Karachi Shipyard & Engineering Works (KSEW). These modern boats are equipped with Stirling-engine AIP systems, which drastically change how they operate underwater.
AIP technology is a massive upgrade for non-nuclear submarines, allowing them to stay completely underwater for much longer without needing to run their diesel engines.
Regular diesel-electric boats have to come close to the surface and use a snorkel to recharge their batteries, a process that exposes them to enemy radar and sensors.
AIP removes this weakness, giving the submarine the ability to stay hidden underwater for up to three weeks, provided it travels very slowly.
When it comes to remaining undetected, AIP submarines can actually be quieter than nuclear ones when moving at a crawl. For coastal defence, surprise attacks, and quiet patrols, an AIP submarine is incredibly hard for enemies to find.
However, this impressive stealth capability brings a severe drawback—a lack of speed.
AIP engines are built to save energy and stay hidden, not to fight in high-speed chases.
To save their limited supply of liquid oxygen, these submarines usually creep along at just four to six knots.
If they are spotted by an enemy, they do not have the sustained speed of a nuclear submarine to quickly escape or change locations.
This speed limitation creates a massive problem for Pakistan's nuclear planning.
For a second-strike weapon to be believable, the submarine must be able to outlast an enemy's anti-submarine defences long enough to fire its missiles after a war begins.
It remains highly doubtful whether a slow-moving AIP submarine could survive in some of the most intensely watched waters in the world.
To actually use the Babur-3 missile against major Indian targets, a Hangor-class submarine would have to sail within 450 kilometres of its objective.
This short range means Pakistani crews would have to navigate directly into waters that are constantly guarded by the Indian Navy’s highly advanced submarine-hunting network.
Over the past ten years, India has poured vast resources into creating a multi-layered anti-submarine warfare (ASW) shield spanning the Arabian Sea and the broader Indian Ocean.
The Indian Navy utilizes a fleet of Boeing P-8I Poseidon aircraft and modern MQ-9B Predator drones to hunt for threats far from the coast.
The P-8I aircraft are armed with torpedoes, specialized radars, and advanced sensors designed specifically to find and destroy silent conventional submarines hiding in shallow or medium-depth waters.
In addition to aircraft, India operates MH-60R Romeo helicopters equipped with dipping sonars and lightweight torpedoes, extending the submarine-hunting range of its warships.
At the same time, the Indian Navy is rapidly adding dedicated anti-submarine corvettes and laying down underwater sensor grids to keep a close watch on vital shipping lanes.
Together, these extensive defences make it exceptionally dangerous for any conventional submarine trying to sneak close to the Indian shoreline.
While true nuclear submarines can race away at high speeds to escape danger or move across oceans, conventional AIP boats are trapped by their battery limits.
Once an Indian patrol spots a Hangor-class submarine, the Pakistani crew would have very few ways to escape compared to a fully nuclear-powered vessel.
This difference is vital. The bedrock of nuclear deterrence is not just having a missile, but ensuring the enemy cannot destroy the launcher before it fires.
Global nuclear powers use dedicated SSBNs that vanish into the deep ocean for months, relying on limitless nuclear power to stay hidden far away from dangerous coastal combat zones.
Because of these limitations, defence experts often label Pakistan’s Hangor and Babur-3 pairing as a "poor man's SSBN."
While it does force India to spend more money and time on hunting submarines, and definitely causes strategic headaches by placing nuclear weapons in the Arabian Sea, it is far from a foolproof system.
Ultimately, this conventional setup fails to offer the unbreakable guarantee of survival that true nuclear-powered ballistic submarines provide to major world powers.
The political consequences of this strategy are extremely dangerous. By mixing nuclear cruise missiles with standard attack submarines, Pakistan erases the line between regular naval warfare and nuclear combat.
In the event of a clash at sea, the Indian Navy might attack and sink a Pakistani submarine without any idea if it was carrying standard torpedoes or nuclear Babur-3 missiles.
This confusion could lead to a rapid and terrifying escalation. If Islamabad loses a submarine, its leaders might not know if it was a routine wartime loss or a direct attack on their nuclear stockpile, potentially pushing them into a severe and aggressive nuclear response.
The danger of starting a nuclear war by accident is exactly why advanced military nations keep their conventional warships and their nuclear deterrence submarines completely separate from one another.
