The Indo-Pakistani War of 1971, which led to the creation of Bangladesh, was not only fought on land and in the air—it also saw intense naval conflict, particularly in the Bay of Bengal and the Arabian Sea. One of the most intriguing aspects of this war was the role of Pakistan’s submarines, especially the infamous PNS Ghazi, which was tasked with hunting down India’s aircraft carrier, INS Vikrant.
This article explores the missions, outcomes, and legacy of Pakistan’s submarines during the 1971 war, with a special focus on their strategic intent, operational challenges, and the mystery surrounding PNS Ghazi.
Background: Pakistan Navy’s Submarine Fleet in 1971
By 1971, the Pakistan Navy had begun investing in undersea warfare, recognizing the strategic importance of submarines in a potential conflict with India. The submarine arm was relatively new but ambitious, with training and procurement support from the United States and France.
Key Submarines in Pakistan’s Fleet:
- PNS Ghazi – Originally the USS Diablo (a Tench-class submarine), transferred from the US in 1964. Long-range capabilities.
- PNS Hangor – A French Daphne-class submarine.
- PNS Mangro and PNS Shushuk – Also part of the Daphne-class fleet.
1. The Strategic Role of Submarines in the War
Pakistan’s strategy in the 1971 war heavily relied on naval deterrence, given India’s superior naval fleet. With a smaller surface fleet, Pakistan saw its submarines as force multipliers capable of:
- Disrupting Indian naval operations.
- Blocking India’s aircraft carrier operations.
- Attacking Indian Navy supply and troop transport ships.
- Forcing India to divert resources for anti-submarine warfare (ASW).
2. The Mission of PNS Ghazi: Targeting INS Vikrant
Perhaps the most high-profile naval operation of the war was the mission of PNS Ghazi, Pakistan’s first and only long-range submarine at the time.
Objective:
- Destroy or disable the Indian Navy’s INS Vikrant, an aircraft carrier stationed in the Bay of Bengal.
- Undermine India’s naval superiority and hamper operations on the Eastern Front (East Pakistan, now Bangladesh).
The Voyage:
- Ghazi departed from Karachi in late November 1971 and headed towards the eastern coast of India.
- It navigated over 3,000 nautical miles, through hostile waters, undetected for several days.
3. The Mysterious Sinking of PNS Ghazi
On December 3, 1971, PNS Ghazi sank off the coast of Visakhapatnam, just as hostilities formally broke out.
Competing Theories:
- Indian Claim: The Indian Navy credits the sinking to INS Rajput, which allegedly dropped depth charges after detecting suspicious underwater activity.
- Pakistani View: Suggests an internal explosion due to faulty torpedoes or mishandling of mines.
Aftermath:
- All 92 crew members aboard Ghazi perished.
- It was a huge loss for Pakistan, both strategically and symbolically.
- The mystery of the Ghazi’s sinking remains a subject of naval folklore and debate.
4. PNS Hangor’s Historic Strike
While Ghazi met a tragic end, PNS Hangor proved to be one of the most successful Pakistani naval assets during the war.
Mission and Patrolling:
- Hangor was deployed in the Arabian Sea, off the coast of Gujarat and Maharashtra.
- Patrolled undetected and collected intelligence on Indian naval movements.
Attack on INS Khukri:
On December 9, 1971, PNS Hangor fired torpedoes at the Indian frigates INS Khukri and INS Kirpan.
- INS Khukri was hit and sank, killing 18 officers and 176 sailors.
- It was the first warship sunk by a submarine since World War II.
- The event was a major psychological and strategic blow to the Indian Navy.
Significance:
- Forced India to move its fleet away from the western coast temporarily.
- Elevated Hangor’s commander and crew to hero status in Pakistan.
- Demonstrated Pakistan’s underwater strike capabilities despite numerical inferiority.
5. Pakistan Navy’s Eastern Front Challenge
Unlike the Arabian Sea, the Bay of Bengal proved difficult for Pakistan’s Navy due to:
- Long distances.
- Limited refueling options.
- No naval bases in East Pakistan.
After the loss of Ghazi, Pakistan had no major submarine presence in the Bay of Bengal. This allowed the Indian Navy to carry out Operation Trident and Operation Python, which severely damaged Pakistan’s coastal facilities in Karachi and contributed to naval blockade success.
6. Technical and Tactical Analysis
Pakistan Submarine Strengths:
- Stealth and shock value: Submarines created fear and uncertainty among Indian ships.
- Training: Pakistani submariners were trained by NATO navies, giving them an operational edge.
- Surprise attacks: Like the successful torpedoing of INS Khukri by Hangor.
Limitations:
- Limited range and endurance: Only Ghazi had long-range capability.
- Communication constraints: Submarines had to surface to communicate, increasing detection risk.
- Logistical limitations: Especially in the eastern theatre.
7. India’s Response to the Submarine Threat
India’s anti-submarine warfare (ASW) efforts were intensified:
- Deployment of ASW ships like INS Rajput.
- Use of sonar-equipped patrol aircraft.
- Escort protocols for major fleet movements.
While India succeeded in neutralizing Ghazi, the loss of Khukri exposed vulnerabilities in ASW preparedness, leading to doctrinal changes in future naval warfare planning.
8. Psychological Impact of Pakistan’s Submarines
Even with limited numbers, Pakistani submarines had a disproportionate psychological impact:
- Indian naval ships operated with heightened caution.
- Naval planning included detours and evasive routing.
- Public morale in India was shaken by the sinking of INS Khukri.
- In Pakistan, submarines became a symbol of resilience and tactical brilliance.
9. Legacy and Lessons
For Pakistan:
- Submarines emerged as a strategic asset, influencing procurement policy.
- PNS Hangor’s success led to more focus on undersea warfare and eventual acquisition of modern diesel-electric submarines from France and China.
For India:
- Losses prompted investment in anti-submarine aircraft, sonar systems, and indigenous submarine development.
- Reassessment of carrier and fleet protection doctrines.
10. Commemorations and Cultural Impact
- Pakistan Navy commemorates December 9 (Hangor Day) each year in honor of PNS Hangor’s feat.
- Indian Navy honors the crew of INS Khukri with memorials and gallantry awards.
- PNS Ghazi and its mysterious end have been featured in books, documentaries, and films (e.g., The Ghazi Attack, 2017).
Conclusion
The role of Pakistan’s submarines in the 1971 war, though numerically limited, was strategically significant. The contrasting stories of PNS Ghazi’s loss and PNS Hangor’s success highlight the high-risk, high-reward nature of submarine warfare.
Despite the overwhelming Indian victory in 1971, Pakistan’s undersea capabilities left a lasting impression on naval strategists across the region. The war also reinforced the importance of maritime power and undersea deterrence in South Asia’s complex security landscape.