News Excerpt:

The first Hangor class submarine, built by China for Pakistan, was launched at a Wuhan shipyard in China.

Basic characteristics of Hangor class submarines:

• The Hangor-class is an export variant of the Chinese Type 039A Yuan class submarine.
• It is a diesel-electric attack submarine.
• It is named after the now decommissioned PNS Hangor, which famously sank Indian frigate INS Khukri during the 1971 war.

Diesel-Electric attack Submarine:

• “Diesel-electric” refers to the mode of propulsion — diesel engines power the submarine when surfaced or snorkelling (as they need air to operate), while a battery, charged by the diesel engine, allows the vessel to operate while submerged. 
• The Hangor-class boasts four diesel engines. 
• It is also equipped with an air independent propulsion (AIP) system, which significantly increases the submarines’ endurance underwater.
• Attack submarines are specifically designed for sinking other submarines or surface vessels using torpedoes, or in modern times, cruise missiles. 
• The Hangor-class has six 21 inch torpedo tubes, and capabilities to launch anti-ship missiles, as well as the Babur-3 subsonic cruise missile, which has a range of 450 km.

Comparison with India’s Kalavari class:

• Pakistan’s Hangor class is the direct counterpart of India’s Kalavari class of submarines which are based on the French Scorpene-class. 
  • India currently operates six Kalavari class submarines, with three more set to be inducted into service by the early 2030s.

• Size:

• • The Hangor class is significantly bigger than the Kalavari class.
  • The Kalavari class has a  displacement of 1,775 tons and is 67.5 m long. The Hangor class, on the other hand, has a displacement of 2,800 tons, is 76 m in length, 8.4 m in width (at its widest point), and has a draught (depth of the vessel below the waterline) of 6.2 m when on the surface.
  • While this probably means that the crew of the Pakistani submarines would lead (slightly) more comfortable lives, in shallow, littoral waters, this is a major drawback, with Kalavari class being much more manoeuvrable. 

• • The Pakistani submarine has a reported top speed of 20 knots (37 kmph), same as its independent counterpart.

• Propulsion:

• • The Kalavari class, like the Hangor class, runs on diesel-electric propulsion. 
  • However, the models India currently operates do not come with built-in AIP. This means that in terms of underwater endurance, the Hangor class potentially has an edge on the Kalavari class.
    • This is significant because submarines’ USP is their ability to be stealthy — much of which comes from their capability of remaining underwater for extended periods of time. 
  • Conventional diesel-electric submarines need to surface to recharge their batteries after a few days (2-5, depending on the battery used), making them detectable to enemy radar and exhaust fumes sensors. 
    • An AIP system can increase submarines’ underwater endurance manifold (upwards of 15-20 days). 
    • The Indian Navy is currently in the process of installing an indigenously developed AIP system to its Kalavari class submarines.

• Armament:

• In terms of armament, the Kalavari class carries six 21 inch, German-made torpedoes, and missile systems such as French Exocet anti-ship missiles, and MICA anti-air missiles. 
• This is likely superior, and more battle tested than Hangor’s armament. 
• Both submarines do not have vertical launch systems (like the ones in India’s nuclear Arihant class), which would allow it to carry bigger cruise missiles like the Brahmos-NG.
• Both submarine classes carry state of the art sensor suites, although details of Hangor’s capabilities in this regard are not out in public.