Loss of the INS Khukri

The sinking of the INS Khukri which was the only warship ever lost by the Indian Navy continues to haunt the minds of naval war planners even today. Perhaps there was a certain amount of overconfidence that crept into the psyche of the Indian Navy after the sinking of the Pakistani submarine Ghazi and the devastating attacks on Karachi, which may have played a major part in the events that lead to the loss of the ill fated Type 14 ASW Frigate. This was the only instance where the otherwise highly effective planning and tactics of the Indian Navy like those used to sink the Ghazi and for the Karachi attacks, did not come into play.

The Pakistan Navy's strength was in their latest Daphne class submarines recently acquired from France, of which there were 3 operational during the war. The deal for the submarines was signed on 25 February, 1966 and was funded by the United States. The first Daphne, PNS Hangor, was commissioned on December 1, 1969,the second, PNS Shushuk on 12 January 1970 and the third, PNS Mangro on 5 August 1970.Hangor and Shushuk arrived in Karachi on December 20 while Mangro arrived a little later due to it's Bengali crewmen, especially technical officers abandoning the submarine while it was commissioning at Toulon following the atrocities by Pakistan against their people. The Daphne class submarines enjoyed sensors and armament  superior to anything in the Indian Navy's inventory. Hangor sailed from Karachi on November 22 for a patrol off the Saurashtra coast. On December 1,she was ordered to shift to the area off Bombay to relieve her sister submarine Mangro, who was completing her patrol.

Immediately after Pakistan initiated the war on December 3,systematic attempts to intercept the Pakistan Navy's shore to submarine broadcasts were commenced. This yielded a series of D/F positions of Pakistani submarines transmitting messages to Karachi. D/F intercepts were obtained on December 7/8 in an area Southwest of the Diu Head, which were classified as a submarine transmission. The war room at Delhi flashed the bearing cuts of these intercepts which were originating 35 miles South-West of the Diu head, to the Maritime operations room in Bombay. Since Diu was the assembly area for ships to be deployed for missile attacks on Karachi, this submarine threat was causing much concern. The 14th Frigate squadron comprising of the vessels Khukri, Kirpan and Kuthar had sailed with the western fleet on December 2. However, Kuthar had suffered a boiler room explosion on December 4 and was towed back to Bombay by the Kirpan for repair. Enroute to Bombay, at midday on December 5, Khukri carried out an attack on a submarine contact and transmitted the information back to Bombay. The first mistake was the decision to deploy the 14th Frigate squadron for the Hunter-Killer operation which required the old frigates to prosecute the contact in an area 55 miles by 50 miles South-West of Diu and on a datum which was already 24 hours late and in sea state 4.Despite the fact that the sonar range of the Daphne's as nearly twice that of the Type 14 frigates, the two frigates sailed out on December 8 without any support from any ASW aircraft to commence the Hunter-killer operation. A wiser choice would have been perhaps, the newer and much more capable Petya class submarine chasers and/or the newly acquired Seaking ASW helicopters which were deployed elsewhere or at least the Talwar class frigates with slightly better sensors though it must be noted that the Khukri and the Kirpan were the only ships along with a few Sea kings available for the task. Although, the odds were heavily in favor of the submarine, the Indian navy refused to let it threaten them at their doorstep and the operation was commenced South of Kathiwar in Gujarat on December 9.

Hangor picked up 2 contacts on her passive sonar at extreme range on a northeasterly bearing, in the early hours of the morning of December 9 when she was off the Kathiawar coast. When they were identified as warships from their sonar transmissions, the submarine began pursuit. When the first attempt to intercept the ships failed, Hangor began snorkeling to increase speed. By the evening on December 9, she was able to make out the pattern of their movement by tracking them with her advanced sensors and concluded that the ships were carrying out a rectangular anti-submarine search. By forecasting their movement, the submarine succeeded by 1900 hrs, in taking up a tactically advantageous position in the path of the patrolling frigates. The linear path followed by the frigates covering a rather small area was the second mistake. The range of the frigates that were moving at a speed of 12 knots was now closing and the Hangor prepared for the attack. At 1915 hrs, she went into action stations and 15 minutes later, came up to periscope depth but could see nothing due to the ships being completely darkened though her periscope radar indicated a range of just 9800 meters. The Commanding officer decided to go down to a depth of 55 meters and make a sonar approach for the final phase of attack. The Khukri was still not aware of the submarine's presence and continued doing slow speed on a steady course on a narrow weave which was a flagrant violation of the anti-submarine doctrine. The reason for this was the attachment of a special device by the Khukri's electrical officer, Lt. V.K Jain, to the Type 14's 170/174 sonar to slightly increase it's detection range. This new device developed with assistance from BARC, was approved by Admiral Kohli to be embarked in the Khukri. The Captain of the Khukri made a conscious decision to do slow speed to increase the range of detection which was however a violation and the third and final mistake. Hangor fired a down-the-throat shot with a homing torpedo at the Northerly ship (Kirpan) at about 1957 hrs from a depth of 40 meters. The torpedo however misfired and Kirpan detected the torpedo going past her and fired her mortars, which after a few salvoes being fired, became non-operational. Without losing time, Hangor turned towards the Khukri which however did not fire it's noisemakers in order to prevent the background noise generated by them from swamping the sonar trying to detect a weak submarine echo. Hangor fired a second torpedo, which exploded under the Khukri's oil tanks. A few minutes later Kirpan returned for an attack in a course that brought her in line with the submarine. Hangor fired a third torpedo and immediately turned away and exited at maximum speed. Kirpan however broke off, turned and outran the torpedo which exploded somewhere in the proximity. According to the Pakistani version, the torpedo exploded near the stern of the Kirpan, badly damaging it and putting her out of action though in reality, Kirpan was not scratched and returned for rescue operations along with the vessel, INS Katchal. However, it must be noted that here, we are analyzing the Pakistani version and the Indian version maintains that both the torpedoes hit the Khukri and Kirpan only heard the hydrophonic echo and reported detecting the other torpedo going past her. Kirpan was faced with a dilemma -should she immediately lower her boats and rescue the survivors of the Khukri which would leave her vulnerable to the submarine or should she leave the area, repair her defective mortars and return with an additional ship to commence the rescue and hunting operations. Under the circumstances, Kirpan made the wise choice of doing the latter. This action however generated some discussions on the ethics of such tactics for quite some time in Indian navy circles.

As the survivors swam away from the sinking ship, some of them looked back and saw the ship going down, and the sea closing over the bridge. And they saw Captain  M.N Mullah seated in the captain's chair on the bridge, as the ship went down. Keeping him company was Lt.Cmdr Joginder Krishen Suri. Captain Mahendra Nath Mullah, aged 45,in the highest tradition of the Navy, preferred to stand by his 18 officers and 176 sailors who went down with the Khukri. When Captain Mullah realized that the ship could not be saved, he gave orders to abandon ship and then directed his second in command, Lt.Cmdr Suri to cast life boats, rafts and buoys into the sea. Many of the younger sailors preferred the false security of the sturdy steel deck under their feet to the unknown dangers of the black sea. The Captain himself pushed them into safe waters, directing them to swim away. When one of them offered the Captain a lifejacket, he brushed him away with the words, “Go on, save yourself, do not worry about me." There was no confusion and no panic due to the Captain's calm transmitting itself to his men. Six officers and sixty-one sailors were the sole survivors left to tell his heroic story. Captain Mullah was posthumously awarded the Maha Vir Chakra (equivalent to the Distinguished Service Order)His colorful personality was not only missed by his young family but also by a host of friends in the Indian and a few from the Pakistan Navy such as the late Admiral H.H.Ahmed and Capt. Afzal Khan who had been his shipmates in the forties.

Following the sinking, a massive hunt codenamed "Operation Falcon" was launched by the Indian Navy for the killer submarine with all available ASW vessels, Sea King helicopters and Alize ASW/Strike aircraft. The IAF joined in and mounted sustained maritime reconnaissance operations. For the next 4 days, all forces were engaged in relentless and coordinated activity and carried out several depth charge attacks. At least 2 salvoes of the numerous charges fired were confirmed to detonate somewhere near the Hangor but only to slightly shake the submarine. Hangor remained deep and crept away at a low submerged speed to avoid detection. She could signal her success to Karachi only a few days later. During this period, one Alize ASW aircraft (piloted by Lt.Cmdr Ashok Roy, Lt.Sirohi and Aircrewman Vijayan) failed to return from a mission on December 10, which involved the investigation of possible warship and enemy air activity near Jakhau on the Indo-Pak border. Pakistani records state that the aircraft was shot down with an AIM-9 sidewinder fired from a PAF F-104 returning from an unsuccessful raid on Okha. Strangely, this was the only confirmed kill by the feared F-104 for the entire war, which incidentally ended with the destruction of at least  8 PAF F-104s instead. Operation falcon was reluctantly terminated at 1900 hrs on 13 December when the Indian forces were nearing the range of shore based Pakistani aircraft.     

Hangor arrived in Karachi on 18 December and her commander Tasnim Ahmed was deservedly awarded a bar to the Sitara- I-Jurat. However, as always, this incident was subject to severe exaggeration by the Pakistani side, which was perhaps not satisfied with this achievement being miniscule, compared to the Indian Navy operations that led to extremely heavy losses for Pakistan. This included the claim of the Khukri sinking with all hands on board, by the electrical officer of the Hangor, R.A. Qadri as well the claim of the Kirpan being damaged. Given the baselessness of such claims, it dilutes the possibility of the Kirpan being fired at for the second time at all and it is more probable that the Khukri was hit by two of the three torpedoes fired by the Hangor, as reported by the Indian Navy. Further claims by the former captain of the Hangor, Tasnim Ahmed, to have disguised his submarine as a "fishing vessel" when approaching the Bombay coast, merits further analysis. The Hangor after being upgraded to fire Exocet missiles along with other subs  of her class, continues to operate regularly with the Pakistan Navy today. The loss of the Khukri will no doubt be a continuing reminder to the Navy of the need to meticulously prosecute a submarine single-mindedly. A Home was constructed for the sons and widows in record time, thanks to the generosity of the citizens of Bombay.  

Sources
Mankekar, D. Twenty-Two Fateful Days: Pakistan Cut to Size. Indian Book Co: New Delhi 1972.

Vice Admiral Mihir K Roy (Retd.) PVSM AVSM, War in the Indian Ocean Lancer International 1995

Story of the Pakistan Navy Naval HQ,Islamabad ,1991.

Vice Admiral GM Hiranandhini (Retd.) NM,PVSM,AVSM, Transition to triumph - Indian Navy 1965-75",    Lancer International 1990.