‘Strategic Funnels’: Deciphering Indonesia’s Submarine Ambitions – Analysis


Historical experience, archipelagic geography, and strategic imperative make submarines a critical asset for Indonesia’s naval defence in spite of financial and other constraints. Overambitious submarine projects, however, are perilous.

By Ristian Atriandi Supriyanto*

In September 2015, Indonesia decided to cut its defence budget for the first time in five years by 6.3 percent, or IDR7 trillion (US$490 million), to IDR95.8 trillion. Slower economic growth and declining rupiah value are cited as the main reasons. As a result, reductions in military procurements are expected. Amid these constraints, however, the government remains firm to endorse ‘big-ticket’ purchases, including submarines. If that’s the case, why do submarines seem central in Indonesia’s naval modernisation programme and broader naval strategy?

Southeast Asia’s underwater strategic environment is getting more crowded. IHS Jane’s predicted in 2011 that regional countries would acquire at least 13 submarines by 2020. Singapore, Malaysia, and Vietnam have acquired submarines in the last two decades or so, while Thailand, Myanmar, and the Philippines have declared their intent to follow suit. Given this strategic trend, it’s tempting to conclude that regional countries are simply playing ‘catch-up’ as a reason behind their submarine acquisitions.

Strategic Imperative

While the necessity to keep abreast with the prevailing strategic trend is common behind any procurement decisions, it is not always that simple.

Submarines are not new to the Indonesian Navy. After Thailand decommissioned its Matchanu-class in 1951, Indonesia became the first Southeast Asian submarine operator with the Whiskey-class boats acquired from the Soviet Union in 1959. Given the absence of other regional submarine operators at that time, Indonesia then clearly did not tailgate others.

The adverse strategic environment at the time, with the Dutch in control of Indonesia-claimed West New Guinea, WNG (West Papua), and the Indonesian Confrontation against the British-backed Malaysia, submarines became a strategic imperative. Underlying this imperative is the archipelago’s location at the crossroads between the Indian and Pacific Oceans, but also the maritime gaps between the islands along Indonesia’s periphery providing foreign maritime powers access into the inner part of the archipelago, known in Indonesia’s naval parlance as the ‘strategic funnels’ (corong strategis).

The importance of strategic funnels lies in their proximity to neighbouring countries, relatively abundant marine resources, or contested maritime space. They include the Sulawesi and South China Seas, where other countries have laid claims on some portions of the two areas, respectively called the Ambalat and Natuna. Reflecting this concern, a new naval base is under construction in the natural harbour of Palu in Sulawesi to support submarine patrols along the Makassar-Lombok Straits axis.

Submarines could play a decisive role when deployed in these sensitive areas. Their stealth and concealment can make them a potent intelligence-gathering platform in peacetime and sabotage in wartime. Although they never saw real combat, Indonesian submarines intensively conducted intelligence gathering and covert special operations ranging from the 1962 WNG dispute to the 1999 East Timor Crisis. In October 1965, two submarines even sailed to Karachi and conducted exercises with the Pakistani Navy in support of the latter after its war against India.

Operational perils

Given their long service history, submarines have become deeply inculcated into Indonesia’s naval traditions. The importance and contributions of the Submarine Service are highly regarded. Its retention becomes even more critical at present when Indonesia’s neighbours are also acquiring and developing their submarine fleets.

Indonesia’s military modernisation plan, the ‘Minimum Essential Force’ (MEF), aims to procure twelve submarines within 2010-2024 timeframe. Currently, Indonesia operates two submarines, the German-built U-209 KRI Chakra and KRI Nanggala. Although refurbished in early 2000s, they were originally built in 1980-81, thus raising doubts about their current effectiveness. In December 2011, Indonesia purchased three South Korean Type-209 Chang Bogo boats with the first induction to begin by 2018, while Russia and France have respectively declared their Kilo and Scorpene bids to supply for the five to seven remaining boats.

On the flip side, the Indonesian submarine experience has revealed a list of mishaps and pitfalls to learn from. While strategically critical, submarines are financially expensive and technically complex to maintain and operate, at least to Indonesia’s standards. Its technological sophistication demands enormous lifecycle costs, which strains the limited naval budget. And this influenced Indonesia’s submarine procurement decision. In 2011, the preferred yet costlier Russian Kilo-class and improved German U-209 were rejected in favour of the cheaper yet less sophisticated South Korean Type-209s.

In addition, technical incompetence plagued submarine construction, operations, and maintenance. The Whiskey-class experience was replete with technical faults and near-accidents, and the fact they were not tropicalised undermined the crews’ morale. Proprietary issues also inhibit the South Korean-Indonesian project to jointly assemble the Type-209s at the latter’s PT PAL shipyard, since the project does not include the original German manufacturer.

A cautionary tale

Although Indonesia wishes to expand its submarine fleet, it is clearly not aimed to outmatch others already in the game. Conservative estimates posit that it would be a long while before Indonesia acquires all twelve submarines, possibly beyond 2024, due to the gestation period in the acquisition process. Even then, they would only reflect the number of Whiskey boats Indonesia originally had. Questions must also be asked about the proficiency of submarine crews and the maintenance support team, the required training and basing infrastructure, and the supply availability of vital provisions, including fuel, spares and ammunitions.

However, the strategic environment in which new Indonesian submarines would be inducted—whenever that is—is going to be different. They would arrive when there would be more submarines already roaming Southeast Asian waters, yet with more novice operators. The history of Indonesia’s Submarine Service—especially its mishaps and pitfalls—presents a cautionary tale about the risk of overambitious submarine projects. Amid a climate of mistrust and tensions surrounding regional disputes, especially in the South China Sea, the introduction of submarines would add uncertainty on regional commitments to a peaceful resolution.

While submarines could add deterrence to individual countries, collectively they could increase the risk of accidents at best, and inadvertent conflicts at worst. This makes it necessary for Indonesia to advocate for greater naval cooperation at bilateral and multilateral levels in order to help mitigate mistrust between submarine-operating countries. Bilaterally, Indonesia maintains regular exercises and patrols with eight countries, while it has increased participation from three to eleven major multilateral exercises since the 1990s.

In the subsurface realm, however, more needs to be done. Indonesia could include more submarine participation in exercises with partner navies. Not only would this improve Indonesia’s own submarine proficiency, but it could also develop interoperability in times of distress, such as a submarine accident, and familiarise Indonesian submariners with others’ doctrines and experiences. Taken together, these efforts are necessary to ensure that submarines remain a potent and reliable war machine.

*Ristian Atriandi Supriyanto is Indonesian Presidential PhD Scholar with the Strategic and Defence Studies Centre at the Australian National University. He was previously an Associate Research Fellow with the S. Rajaratnam School of International Studies (RSIS), Nanyang Technological University, Singapore.


RSIS Commentaries are intended to provide timely and, where appropriate, policy relevant background and analysis of contemporary developments. The views of the author/s are their own and do not represent the official position of the S.Rajaratnam School of International Studies (RSIS), NTU, which produces the Commentaries. For any republishing of RSIS articles, consent must be obtained from S.Rajaratnam School of International Studies (RSIS).

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