Operation Trident: Remembering a Historic Naval Victory

Today, December 4, is the 43rd anniversary of one of the most audacious naval operations undertaken since World War II: the attack on Karachi port by India’s Killer Squadron 25.

Our tale begins with 1965. The war India fought under Lal Bahadur Shastri was initiated by a Pakistani adventure on the Indian border. Sardar Post in the Rann of Kutch in Gujarat near Kanjarkot saw Pakistan’s 51st infantry Brigade crossing the international border and attacking the local Indian CRPF party on 9 April.

After a brief clash, the CRPF party beat a retreat. Pakistan had captured the Kanjarkot area for the moment, but the local conflict lasted for about two months. On June 30, a ceasefire agreement was signed where Pakistan agreed to withdraw forces. However, India agreed to allow Pakistan to use a road it had constructed in Indian Territory.

Pakistan’s Sardar Post intrusion was to test the response and resolve of Shastri’s India. The outcome of strengthened Pakistani resolve. Three months later, a full blown war began with two Pakistani operations: Operation Gibraltar and Operation Grand Slam, both focused on Jammu and Kashmir.

While the Sardar Post affair was the Pakistani army’s  initiative to test waters before a full blown war, a similar exercise was employed by the Pakistani Navy: Operation Dwarka.

In the afternoon, a ship was spotted far out in the sea, going from Bombay to Okha—upon inquiry it was found to be INS Talwar, patrolling the area. At around 5:30 PM, a ship was spotted sailing in the opposite direction. The ship sailed near the coast while keeping its lights on, adjusted back and forth, and finally settled down, turning all lights off. Was it INS Talwar again, stopping for some maintenance? No, it wasn’t.

The ship started firing its shells on Dwarka city, and the shelling continued for more than 20 minutes. A fleet of seven Pakistani ships—PNS Babur, Khaibar, Badr, Jahangir, Alamgir, Shah Jahan and Tipu Sultan—had chosen Dwarka for attack, to destroy the radar station. Fortunately, most of the shells failed to explode, and there were no human casualties. During this mayhem, INS Talwar was in Okha (a few miles north of Dwarka) for repairs, aware of the explosions and transmissions from Pakistani warships—but could do nothing in response. Other Indian warships were ordered to not get involved. The Pakistani fleet soon headed back to Karachi, with no casualties.

In 1970, Admiral Sardarilal Mathuradas Nanda had taken charge as the eighth Chief of the Naval Staff of the Indian Navy. By mid-1971, it was evident that another India-Pakistan war was approaching, with the East Pakistan/ Bangladesh issue as the trigger.

The Admiral, along with Chief of Army Staff General Sam Manekshaw, aimed to also attack rather than merely defend. The plan chalked out for the navy was:

1. Surround the East Pakistan coast and block all ports for enemy activity, which meant denying trapped Pakistani soldiers opportunities to flee.

2. Attack Karachi. All the external trade and transfer, including that of arms and ammunition, took place at Karachi port. It was also the headquarters of the Pakistani Navy as well as its principal oil storage facility

Admiral Nanda organized the navy into two independent fleets—Eastern and Western—on October 16, 1971. Considering the importance of manning the sea border of East Pakistan, the air-craft carrier Vikrant was transferred to the Eastern fleet.

As far as Karachi was concerned, the plan was to attack Karachi with missile boats. This was Operation Trident.

(Note: Users unaware of warship types can check here for reference).

India had acquired 8 Osa-I class missile boats from the Soviet Union in 1969. They were inducted into the navy and categorized as Vidyut class missile boats.  The boats were tested near an unknown island off the coast of Bombay—monitored by Ilyushin Il-14 and Alizé aircraft (to prevent any sightings by other aircraft). After Pakistan declared a national emergency on November 23, 1971, three of the missile boats were deployed at Okha to carry out patrols and gain experience. The entire missile boat fleet was labeled as Killer Squadron 25 (K-25) and was placed under Commander Babru Bhan Yadav.

Due to their obvious weaknesses, such as shorter radar range and a less-than-sufficient anti-aircraft system, a squadron made exclusively of missile boats was not enough to attack Karachi. Two anti-submarine Arnala class (originally Soviet Petya class) Corvettes (smaller-size frigates)—INS Kadmat and INS Katchal—were added to the squadron; as the Corvettes had better radar, anti-aircraft and anti-submarine defense systems, they were to provide cover to the missile boats from air or submarine attacks. The Corvettes were also intended to provide communication, control and identification of enemy targets (due to better radar systems). Due to unexplained reasons, INS Kadmat was replaced by INS Kiltan at the last minute.

Now that the squadron was formed, another worry was the low range of missile boats due to small  fuel tanks (as well as a different fuel type from that of the Corvettes). This was solved by establishing special fuel depots at Okha and Diu (on Gujarat coast). Also, a fleet tanker ship INS Poshak  was added to the squadron to be positioned halfway from Karachi, to refuel the missile boats both before  and after the final lap of the attack.

Air Attack on Karachi and Badin

Any successful military attack on enemy soil has to involve neutralizing its air-attack capability. In this case, it was even more important, as missile boats do not have adequate air defense systems. There were two air bases which would have served as springboards for Pakistani air attack—Masroor (Karachi) and Badin. The request to bombard these two was promptly raised by Admiral Nanda. The proposal was executed swiftly.

December 4 saw day-long air strikes on Masroor and Badin. The strikes destroyed the Badin radar station and warehouse. Pakistani navy thought these were just routine firing.

Operation Trident Begins

4 December, 1971. The squadron started its 500-km-long journey to Karachi from Okha. Due to shorter travel ranges, missile boats were being towed till a certain distance to Karachi harbour. Complete radio silence was to be kept till the squadron reached closer to Karachi naval base. The squadron formed an arrow-head formation, with INS Nipat leading the way, INS Nirghat five miles to its port (left) and INS Veer on starboard (right). Another advantage for the Indian squadron was the fluency of its crew in Russian. This would prove to be very useful while communicating.

2000 hrs: The squadron inched up to Karachi at a speed of 24 knots (approximately 44.5 kmph). Dusk had fallen. The squadron had a stroke of misfortune as well as good luck. The misfortune had to do with the fact that it was a full moon night, making it frighteningly easy for the squadron to be spotted as six white stripes on the pristine blue Arabian sea by a Pakistani aircraft (as a matter of fact a Pakistani patrol aircraft did indeed notice ‘unidentified ships traveling north-west’)

2100 hrs: A few faraway targets had started appearing on radars of Corvettes (due to anomalous propagation—periodic but unique atmospheric conditions of Arabian sea between Gujarat coast and Karachi which allows electromagnetic waves to travel longer distances in a recognizable form), but were not attacked as they were not considered worthy of wasting missiles. The squadron simply changed course briefly to avoid them.

2145 hrs: Distance to Karachi was now 80 km. The squadron had a stroke of good luck. Pakistani navy had commanded all non-navy ships to stay out of the Karachi harbour at a range of minimum 112 km between dusk and dawn. So any beacon identified on the radars of the killer squadron could be safely predicted to be a Pakistani warship. Final checks on equipment in all vessels were performed.  The radars were constantly being monitored on all ships (INS Poshak stayed behind in Mangrol and INS Vidyut stayed outside Karachi harbour to act as a mobile refueling depot and armed backup respectively).

Attacking Pakistani Ships
2200 hrs: The radar in INS Nipat started beeping, showing two enemy targets. The first was 45 miles north-west, and the second 42 miles north-east. An excited Commander B. B. Yadav quickly broke the radio silence and informed Rear Admiral Kuruvilla. Operation Trident had reached its most crucial leg.

Karachi harbour was now 35 km away.

First target on the radar, now around 27 km away, had started moving towards the missile boat. It was the Pakistani destroyer PNS Khaibar, originally HMS Cadiz of the UK Royal Navy, acquired by Pakistan in 1956. It was a huge vessel, weighing 3,290 tonnes when fully loaded. INS Nirghat and INS Kiltan were instructed to deal with the oncoming threat.

2245 hrs (PST): INS Nirghat moved swiftly, locking on the target and launching its first Styx missile. The missile took off towards the sky in the shape of a bright light, and then zoomed down towards PNS Khaibar. Khaibar mistook the missile for an aircraft diving in and started firing its Bofors anti-aircraft guns. The missile struck Khaibar on the starboard side below water level. The ship instantly lost propulsion, plunged into darkness and huge flames shot up due to an explosion in the boiler room. Khaibar started slumping towards the side of the explosion and sent an SOS to naval headquarters: ‘Enemy aircraft attacked in position 020 FF 20. No 1 Boiler hit. Ship stopped.”

Clearly, the Pakistanis had no clue. All anti-aircraft guns located at Karachi harbor and Masroor air base now started firing, in search of supposed Indian aircrafts.

2249 hrs (PST): INS Nipat launched its first missile, which struck Khaibar on the starboard side and proved to be a deathblow. The ship exploded, sending shockwaves across Karachi city. The sky was lit up in flames as ammunition on the ship exploded.

2300 hrs (PST): Meanwhile, after receiving the SOS, minesweeper PNS Muhafiz had changed direction to save surviving Khaibar crew members. Now it was the turn of INS Veer to fire its first missile, which struck Muhafiz squarely. The minesweeper exploded and disintegrated.

2320 hrs (PST): INS Nipat now engaged two contacts, MV (Merchant Vessel) Venus Challenger and Destroyer PNS Shah Jahan—originally HMS Charity of the Royal Navy.

MV Venus Challenger was completely dark, as it was a supply ship present inside the harbour. The ship was carrying US-supplied ammunition from Saigon for the Pakistani army and air force. PNS Shah Jahan was a warship almost the same size as PNS Khaibar, weighing 2,520 tonnes fully loaded. The second missile from INS Nipat struck MV Venus Challenger, blew up the ammunition and the ship sank in less than eight minutes.

The third missile from INS Nipat struck PNS Shah Jahan, crippling it beyond repairsafter INS Nirghat  struck it with its second missile. PNS Shah Jahan did not sink due to its partitioned structure in its underwater base, which prevented the base from filling up with water completely, but was rendered ineffective for the rest of the battle. INS Veer fired its second and third missiles at two separate targets: PNS Tipu Sultan and PNS Tughril, sinking both of them.

Pakistani naval headquarters sent a message for help to Masroor air base in Karachi, but received no reply. Reason: The Indian air force was attacking the base, in coordination with the naval attack.

There were no more contacts left to engage. The threat of a retaliatory Pakistani air attack was looming large and anxiety had started to set in. The squadron was now ordered to assume anti-aircraft readiness, and all vessels were ordered to act individually and turn back to the pre-decided rendezvous point near INS Poshak for refueling and return journey. Two vessels did not return immediately. One of them was INS Kiltan, which got the message late due to a brief fade-out in communications.

Attacking Karachi Port

The second vessel was Commander B. B. Yadav’s INS Nipat. Nipat continued towards Karachi harbour, caring neither for the lack of surprise nor a possible air attack. Nipat was now just 15 km from the harbour, and figures of crucial oil tanks and refineries started showing up on its radar. Nipat took aim, and launched two Styx missiles (missiles had in-built metal detectors, mistaking metal tanks with ships ). The second one misfired, but the first struck the oil depot and refinery.

A coded message was transmitted to Indian naval HQ at Bombay.  Jubilation and celebration swept through headquarters at the success of a truly audacious attack.

Turning Back
There was still a major challenge left. The squadron had to now turn back, with a longer return journey towards Mangrol (not Okha, as the Pakistani air force might be anticipating Okha as the return destination) and then Bombay. Nipat and Kiltan turned around sharply and were immediately followed by Pakistan’s Jaguar patrol boats. Radio silence had to be maintained. Due to a sharp turn and late arrival, Kiltan was initially mistaken by INS Veer (already at a reduced speed due to machinery issues) as a Pakistani vessel, and was even preparing to fire a missile before things were cleared via urgent communication. Veer, Nirghat, Vidyut, Kiltan and Katchal had now started to head back towards Mangrol, a journey that would take them around 10 hours.

Nipat was left behind, and then experienced a problem. One of the oil pipes was broken and oil was getting dumped inside the engine room. One of the two running engines now had to be turned off, and this reduced vessel speed to less than half. Engineers quickly got down to manually transferring spilled oil to the other fuel tank which still had a fuel pipe in good condition. The problem was, with such a reduced speed, it was impossible to reach Mangrol in time with the rest of the fleet—let alone Bombay.

Reaching Mangrol and Bombay
Commander Yadav then did something wild and imaginative. He ordered Nipat to turn 90 degree east, towards the Gulf of Aden! The logic behind such a move was that the Pakistani navy and air force would never search for an Indian missile boat towards Aden or the Coast of Makran (Balochistan). Nipat turned, disappeared and lost communication with the group.

The rest of the squadron reached Mangrol to refuel for the last leg of their journey towards Bombay. The air retaliation from Pakistan never came, as attacks by the Indian air force had damaged Pakistani air bases. Nipat, however, was nowhere to be seen. After Pakistan’s announcement of its planes sinking one Indian ship, the rumour spread to the Bombay naval HQ as well.  It was assumed that Nipat was destroyed and Commander Yadav and his crew had become martyrs. The misunderstanding even prompted the defense ministry to announce a posthumous gallantry award for Commander Yadav.

Finish and Glory
To everyone’s relief, Nipat appeared on the horizon of Mangrol around afternoon (from where it had to be dragged by INS Katchal towards Bombay as its second engine too failed). The news from Pakistan radio turned out to be hilariously misplaced—it was a Pakistani vessel which had been mistakenly bomed and sunk by Pakistani aircraft and not an Indian one.

And thus, one of the most audacious naval operations undertaken since World War II came to an end. It was quite an extraordinary attack on an enemy port by a fleet consisting entirely of missile boats.

(Sources/references: Yuddh ’71 (Harshal Publications),Safari, Issue-19 (Harshal Publications), Bharat Rakshak, India Defense Review, India Defence Forum)