Hangor submarine launch: Is Pakistan eyeing naval deep-strike capability?

Pakistan is buying eight Chinese Hangor-class submarines equipped with state-of-the-art sensors and weapons to strike targets at standoff ranges

China on Friday launched the first of the eight advanced Hangor-class stealth submarines it is building for the Pakistan Navy, even as the Indian Navy's next major submarine programme, Project 75 (India) or P75-I, is facing delays.    

The launch ceremony for the submarine was held on Friday at Wuchang Shipbuilding Industry Group’s Shuangliu Base in the Chinese city of Wuhan. The ceremony was attended by high-ranking officials from China and Pakistan.  

The launch was announced by the Pakistan Navy and reported by the South China Morning Post, among others.  

Why does Pakistan want Hangor-class submarines?  

The Hangor-class submarines could be equipped with the Babur-3 submarine-launched cruise missile (SLCM), which has a range of 450 kilometres and was first tested in 2017.   

 

Open source analysis indicates that this could provide Pakistan with a limited second strike or deep strike capability, which has been on Islamabad's mind due to India's Arihant-class nuclear-powered ballistic missile submarines.

  

However, no official confirmation has been made about the Hangor-class submarine's weapon systems.  

Also, the Hangor-class submarines are not equipped with a vertical launch system, unlike India's Arihant-class submarines.  

What else can the Hangor-class submarine do?  

These submarines will be equipped with state-of-the-art sensors and weapons to strike targets at standoff ranges.  

While many of the specifics about the submarine remain unknown, online media outlet Naval News has reported that they are an export variant of the Chinese Navy's Type 039A/041 Yuan-class submarines.  

A diesel-electric attack submarine, the Hangor-class vessel will also be equipped with an air independent propulsion (AIP) system that significantly increases its underwater endurance, according to a number of analysts. However, the Pakistan Navy has not officially commented on the submarine's propulsion system.  

While it is powered by diesel engines when on the surface or snorkelling, the electric battery, charged by the diesel engines, runs the vessel when submerged. A submarine's diesel engines need air to operate.  

However, the Hangor-class submarine's most important capability would be that it could remain underwater for extended periods of time, if it is equipped with an AIP system. 

Most diesel-electric submarines are forced to surface to recharge their batteries after a short period, measured in a few days, which makes them vulnerable to enemy sensors.  

Meanwhile, an AIP-equipped submarine is stealthier in comparison, since it possesses a much greater underwater endurance, which can extend up to 20 days. This reduces the period it is on the surface, exposed to the enemy. 

An AIP system refers to any means of marine propulsion that allows a conventional, non-nuclear submarine to operate for extended periods of time without surfacing or using a snorkel, which is needed for access to atmospheric oxygen.  

Pakistan signed a deal with China Shipbuilding & Offshore International Company Ltd (CSOC) to buy eight Hangor-class submarines during Chinese President Xi Jinping's visit to Pakistan in 2015.  

The Financial Times had reported in 2015 that the submarine contract could be worth up to $5 billion.  

While four of the submarines are to be built in China, the remaining four are meant to be constructed at Pakistan's Karachi Shipyard & Engineering Works Ltd under transfer-of-technology.  

What about India's next-generation submarine plans?  

Formulated in 1999, India's next-generation submarine programme, P75-I, has been facing delays.  

The Indian Navy is still reportedly scouting for a proven AIP system for the submarines to be built under P75-I. The Navy insists that these submarines have to be AIP-equipped.    

Envisaged in 1999 for the indigenous construction of conventional submarines at two Indian shipyards, P75-I was formally initiated in 2007. Under the plan, the Navy was to induct 12 submarines by 2012 and an additional 12 by 2030.

  

To bridge the Navy's capability gap in the meantime, a contract for six French Scorpene (Kalvari-class) submarines was signed in 2005. The first of the Kalvari-class submarines, built at the Mazagaon Docks, was inducted in 2017. While the sixth submarine is slated for induction this year, approval was given for three additional vessels in 2023.  

However, the China-Pakistan Hangor-class submarine project is also running behind schedule. The initial plan was to deliver the eight vessels between 2022 and 2028. While the first four submarines were to be delivered in 2022-2023, the final four were to follow in 2028. However, the first submarine has been launched now in 2024.  

How does the Hangor compare with India's Kalvari subs?  

Compared to India’s latest submarines, the Kalvari class based on the French Scorpene vessels, Pakistan's Hangor-class submarines will be significantly larger.   

While both the Kalvari-class and Hangor-class submarines are conventionally powered diesel-electric vessels, the former are not equipped with an AIP system.  

Thus, the Hangor-class boats will have an edge over India's Kalvari submarines in underwater endurance.  

However, the process to install an indigenously developed AIP system on the Indian Navy's Kalvari class submarines is currently underway, and their armament is more combat-proven than the Hangor's.   

At present, the Pakistan Navy operates three Agosta 90B submarines equipped with AIP systems and two Agosta 70 diesel-electric vessels.