Upgrades At Last: Keeping India’s U209 Subs Afloat
India’s Navy will be hard-pressed to keep an adequate submarine force afloat over the medium term. Its 6 “Project 75” Scorpene Class submarines won’t begin deploying before 2019, 2 of its 10 aging Kilo Class boats have been wrecked, and its 4 U209 submarines are quickly approaching the end of their useful lives.
Nevertheless, if submarine strength is to be maintained while waiting for the Scorpenes, it’s the U209s that are going to have to fill the numbers gap…
India’s Shishumar Class
Shishumar Class submarines are 64.4m long U209/1500 boats, displacing 1,850t fully submerged and powered by diesel-electric motors. They carry a crew of 40. The 1st boat, INS Shishumar [S44], was commissioned in September 1986. The last boat, INS Shankul [S47], was commissioned in May 1994. The boats have received mid-life upgrades, but details are sketchy. Sonar upgrades are believed to have been part of the work.
INS Shishumar will turn 30 years old in September 2016, and the stress of repeated water compression creates a safety limit for submarine life extensions. If the standard 30-year limit is respected, the submarines will have to leave service in 2016 (Shishumar & Shankush), 2022 (Shalki) and 2024 (Shankul).
The current round of upgrades is reportedly targeted at INS Shalki [S46] and INS Shankul [S47], leaving a decision regarding the older INS Shishumar [S44] and INS Shankush [S45] for later. Those upgrades appear to revolve around their weapon fit.
These submarines currently have 14 storage slots for heavyweight torpedoes, firing through 8 x 533mm torpedo tubes. India uses the Atlas Elektronik AEG SUT-66 Mod-1 wire-guided, active/passive homing torpedo with active and passive sonar, as well as wire guidance. It has a range of 28 km at 23 knots, dropping to 13 km at 35 knots fast pursuit, and delivers a 260 kg RDX warhead. Up to 24 mines can also be strapped on externally.
Planned weapon upgrades in this round include the ability to fire sub-sonic UGM-84L Harpoon Block II anti-ship and land attack missiles, with an operational range of around 140 km. Each Harpoon missile container would take up a storage slot otherwise reserved for a torpedo, but their presence would vault the Shishumars ahead of even India’s Russian Sindhugosh (Kilo) Class submarines, thanks to the Harpoon’s GPS guidance and land attack capability.
India will also need to upgrade or replace its AEG SUT-66 torpedoes, and reports indicate that this is underway. The nature of the upgrades hasn’t been specified, beyond 15 – 17 years of torpedo life extension.
Other Upgrade Options
Some level of structural inspection and remediation should be expected in any Shishumar Class upgrade. The question is how much, and that may depend on what any inspections find. Beyond that, weapons and propulsion are the most promising upgrade areas for any conventional SSK.
If India wished to replace their existing torpedo stocks, the Atlas DM2A4 Seehecht (Seahake) heavyweight torpedo offers greatly improved sonar and fiber-optic guidance, while extending torpedo range to over 50 km at 50 knots. The Seahake Mod4 ER goes a step further, and has hit an astonishing maximum range of 140 km. Unfortunately for the Shishumars, the Scorpene submarine’s planned torpedo buy remains in limbo. India favors the Finmeccanica WASS Black Shark torpedo that comes pre-integrated with the Scorpene, but the government’s issues with Finmeccanica have stalled any purchase. Atlas Elektronik’s Seahake was the other competitor in India, and in the unlikely event that it’s eventually picked, the door might open to refitting the Shishumars with Seahakes as well. Otherwise, it would be an expensive weapon buy with nowhere to go once the Shishumars leave service.
A September 2004 proposal from Siemens of Germany offered India an Air Independent Propulsion (AIP) system upgrade for the Shishumar Class, and the necessity of cutting through the hull to add this block section would have made additional life extension work sensible. India was unable to seize the opportunity at that time. The Shishumar fleet’s age makes it very unlikely that such an expensive upgrade would be considered now, despite its stealth benefits for the boats.
Contracts and Key Events
Aug 29/14: DAC OK. The new BJP government’s Defence Acquisition Council (DAC) makes a number of key moves, beginning with cancellation of the 197-helicopter Light Utility Helicopter competition. At the same time, however, DAC cleared INR 48 billion to cover mid-life upgrades for 6 submarines: 4 Sindhughosh (Kilo Class) and 2 Shishumar (U209 Class) boats. Sources: Business Standard, “Govt clears defence deals worth Rs 17,000 cr” | Defense News, “India Cancels $1 Billion Light Helicopter Tender” | Financial Express, “Make in India kicks off with defence deals” | Indian Express, “Centre scraps light utility helicopter tender, opens it to Indian players” | NDTV, “Modi Government Drops Rs 6000-Crore Foreign Chopper Plan, Wants ‘Made in India'”.
2 upgrades approved
July 1/14: Weapons. The US DSCA announces India’s formal export request for a possible initial sale of 12 UGM-84L Harpoon Block II Encapsulated Missiles, 10 UTM-84L Harpoon Encapsulated Training missiles, 2 Encapsulated Harpoon certification training vehicles, containers, spare and repair parts, support and test equipment, personnel training and training equipment, publications and technical data, and other forms of US Government and contractor support. The estimated cost is up to $200 million.
“This Harpoon missile system will be employed on the Indian Navy’s Shishumar class submarine (Type-209) and will provide enhanced capabilities in defense of critical sea lines of communication. India has already purchased [AGM-84] Harpoon missiles for integration on Indian Air Force Jaguar aircraft and Indian Navy P-8I maritime patrol aircraft. India will have no difficulty absorbing these additional missiles into its armed forces.”
The principal contractors will be the Boeing Company in St Louis, MO (Harpoon); and Delex Systems Inc., in Vienna, VA. In accordance with the Indian Defense Procurement Policy, a contractor may be expected to conclude offset agreements with the Government of India.
Implementation of this proposed sale won’t require any additional US Government or contractor personnel in India, but visits will be required on an intermittent and temporary basis for program, technical, and management oversight and support requirements over a period of about 5 years. Sources: US DSCA #14-21, “India – UGM-84L Harpoon Missiles”.
DSCA request: Harpoon Block II (12)
June 23/14: Batteries. India’s government new has decided to take swift action to replace submarine battery stocks, as India works to keep its existing fleet in the water until 2016.
The Navy has issued an RFP to buy 7 Type-I battery sets (248 batteries each) for Russian-made Kilo-class submarines, plus 2 sets of Type-II batteries (540 batteries each) for their U209 Shishumar Class. They’re also buying new cables. The Kilo Class submarine INS Sindhuratna needs those cables to become operational again, and the belief that old and dangerous battery sets may have played a role in Sindhurakshak’s sinking (q.v. Feb 26/14) has made it clear that the red tape blocking new buys needed to be cut.
What the report doesn’t say is whether a resolution was found for the fact that “the Defence Ministry had stopped purchases from a particular vendor.” Sources: Mail Online India, “Centre rushes to buy new submarine batteries as Navy suffers shortage”.
Nov 11/13: Weapons. The Indian Navy picks OEM Atlas Elektronik to upgrade 64 German-built AEG SUT-66 Mod.1 heavyweight torpedoes deployed on the Shishumar Class. What they don’t say is how extensive the upgrade will be, beyond mentioning that it will give the torpedoes another 15-17 years of service life. Sources: Indian Express, “Navy to upgrade torpedoes, sonars of warships soon” | SP’s Naval Forces, “Atlas Elektronik to upgrade Indian Navy torpedoes”.
Sept 9/13: India is moving to try and expedite defense proposals that include an upgrade for the Shishumar class (HDW Type 209) to equip them with anti-ship missiles, a fire control system upgrade for its Sindhugosh (Kilo) submarines, simulators for training the crews on weapons firing, and the Project 75i tenders for a new range of conventional submarines.
Sources said the upgrade for the Shishumar class of submarines is likely to be cleared first. The upgrade for two of the four submarines of the class with the Navy is likely to cost under Rs 1,000 crore (about $), which will include the purchase of nearly 100 Harpoon missiles from the USA.
The submarine’s original designers at TKMS subsidiary HDW will reportedly be roped in for the upgrade and training of the crew. While INS Shalki and Shankul will be upgraded, a decision on the other 2 will be taken later. To reduce crew training costs, and conserve the Shishumar fleet’s dwindling operational life, India also plans to buy 2 torpedo simulators will from Germany. Sources: Indian Express, “Navy set to upgrade, boost existing fleet”.
June 20/12: The Navy is planning a major upgrade for its Shishumar class of submarines by equipping them with tube-launched UGM-84 Harpoon sub-sonic anti-ship missiles.
“Sources said the Navy had moved a proposal to the Ministry of Defence to equip the fleet with Harpoon anti-ship missiles when the submarines go for the next round of refits. In the first step, the Navy plans to upgrade the INS Shalki and Shankul with the Harpoon system, followed by the 2 older submarines in the class…. At present, the combat range of the Shishumar class is limited to under 20 nautical miles — the effective range of its AES SUT torpedoes…. The Kilo Class submarines are equipped with anti-ship Klub S missiles with a range of just over 100 nautical miles.”
Sources: Indian Express, “Navy plans missiles for four submarines”.
- Bharat Rakshak – Shishumar Class.
- DID FOCUS Article – Ships Ahoy! The Harpoon Missile Family.
- DID FOCUS Article – India’s Project 75 SSKs: Too Late to Save the Submarine Force?