SRI LANKA: Sinking of A 520/MV Invincible in Trincomalee

Paper no. 2700 13-May-2008

SRI LANKA: Sinking of A 520/MV Invincible in Trincomalee

Guest Column by Commodore RS Vasan IN (Retd)

(The views expressed are his own)

Reports indicate that a SLN logistic support ship was sunk at about 0223 hrs on Saturday 09 May 2008. The ship was next to Ashroff Jetty at Trincomalee and was being loaded with explosives to be carried to KKS. This ship itself came in to the possession of the SL Navy by a court order way back in 2003 when it was apprehended transporting illegal migrants in Southern Sri Lanka. The ship was more than 38 years old and was regularly used for logistic support for the Sri Lankan armed forces. Ironically the earlier name of the ship “Invincible” did nothing to prevent the ship from meekly submitting to the designs of the black tigers.

Before coming to a conclusion on what would have caused the sinking it would be in order to examine the methods/options, which could be adopted for launching of such attacks. There are many options as far as underwater attacks are concerned.

The First is an attack by a suicide diver strapped with explosives who could approach the target underwater with out being detected, cling on to any vulnerable portion of the ship and detonate the explosives .The results of an underwater explosion on the hull are always a devastating one and invariably results in breaking up of the ship and subsequent sinking. In this case some reports have indicated that the ship sank with in 13 minutes of the attack. Apparently there was no loss of lives.

The Second method is to attach a limpet mine to the underwater hull of the ship and this could be set to explode either with a timing device or with a fuzing device that could activate with sound or pressure or movement in its vicinity.  In such cases the diver could get away from the scene of action. However during the process of his retreat from the ship if he is detected, the success of the operation would be compromised and would lead to bottom searches of the target ship and neutralization of the limpet mine. The black tigers would not have liked any compromise and thus would have preferred the suicide option.

Related aspects of carrying out such attacks have been discussed in an analysis of the sinking of a Fast Attack Craft on 22nd March 2008 vide

The depths off Trinco and even alongside berths are very much favourable for such attacks. I can vouch for this fact from my first hand experience in the harbour from where I operated for some time during the early 90s.The fact that the ship was stationery and the crew perhaps busy with the loading operations may have contributed to not detecting the diver and the resultant success of this operation by the Commandos of the LTTE.

The Third option is for the human torpedoes to be used against the target. The SL Navy officials have apparently has ruled this out.  From the point of view of the Sea Tigers, the suicide attack would indeed have been the choice of execution against heavily defended targets.

The pattern of operations suggests that the tactic adopted is similar to the one that was followed during the sinking of a fast attack aircraft on 22nd Mar 2008 except that in the former case, the FAC was moving at sea and in the latter case the target was stationery in a protected harbour.

Having examined all the three options, based on the facts and reports available so far, it can be inferred that the underwater defence systems in place were breached by a suicide diver who succeeded in detonating explosives next to the old underwater hull of the ship MV A 520 resulting in the sinking of the logistic support vessel

Comments on the preparedness of SL Navy

It appears that the established precautions for thwarting an underwater attack were either not in place or failed to prevent the impending attack. The standard practice for preventing underwater attacks by divers is to have boat patrols and drop random scare charges to deter the divers. Divers also search the bottom of the ships at regular intervals to spot any explosive that may have been attached.  The shipside is rigged with lights for ready use and upper deck sentries are posted to spot any activity that may raise suspicion of the presence of saboteurs.

Most Navies adopt a calibrated degree of preparedness to ensure that the threat is tackled in a timely and efficient manner by denying the use of the waters to saboteurs in a protected harbour.  Many navies also use their sonars to cause damage to the eardrums, impair hearing and deter the diver by use of high underwater sound power. Such measures depend on the threat perception and the degree of alertness assumed in a particular location. In addition it is also a practice to have grapnels towed behind the patrolling boat (similar to trawling operations) to cause injury to the saboteurs. Whether all these measures were in place is not known.

Sri Lankan Navy has been credited with the sinking of   more than a dozen logistic ships of the LTTE, which were employed for carrying the essentials from many parts of the Indian Ocean for sustaining the war effort. The ship that was sunk was apparently also used in the operations against three logistic ships of the Sea Tigers off Coco Island in 2007.

This is the second such sinking in the last two months. While the names of the three suicide attackers were given out soon after the attack on the Fast Attack Craft two months ago, all that has been mentioned in this case by the Tamil net is that the Commandos from Kangkai Amaran unit of the Sea tigers executed the attack. This unit apparently was named after a Senior Commander of the Sea Tigers who was killed in Mannar District in an attack by the Deep Penetration Unit of the Sri Lankan Navy in Jun 2001.

In conclusion, it is clear that that the Sea tigers still have the capability to surprise the SL Navy and would like to regain the control of the seas which is so essential for the tigers to replenish from many parts of the world including southern India.

The use of underwater divers for attack while not being novel has the potential to cause serious damages, loss of morale amongst the forces and disrupt planned activities at sea. The success of such operations would have deleterious impact on the ongoing operations of Sri Lankan forces, which are trying to move supplies and military hardware through the eastern sea routes to KKS. One can safely assume that more such attacks and all the options discussed above would be exercised by the Sea Tigers to wrest the initiative from the Sri Lankan Navy, which has enjoyed some successes in the recent months.

(The author with distinguished naval and coast guard service for over 34 years is presently with Observer Research Foundation and is steering the Maritime Security Programme under the aegis of International Security Studies (ISS), headed by General VP Malik former Army Chief)


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