NEXT Monday, the usually quiet skies over the Natuna Islands will be abuzz as Indonesia's air force stages its largest annual exercise over the South China Sea, in a scenario that involves recapturing an airbase from the enemy and reclaiming control over Indonesian territory.
Close to 2,000 officers and 43 aircraft - including eight Hawk jets, six Sukhois, five F-16s and four Super Tucanos - will be deployed.
Codenamed Angkasa Yudha - battle for the skies - 2013, the exercise comes at a time when tensions in the South China Sea remain high and a key concern for military strategists.
"The exercise aims to test the strength of our personnel and weapons and improve their professional combat capabilities," an air force spokesman, First Marshal Hadi Tjahjanto, told The Straits Times.
Mr Ristian Atriandi Supriyanto, an associate research fellow of the S. Rajaratnam School of International Studies, told The Straits Times that while these drills are an opportunity to test defence capabilities, they also send a political signal.
"In this sense, the exercises are meant to reassert and demonstrate Indonesia's sovereignty in the Natunas," he said.
The oil- and gas-rich Natunas are located between the Malaysian peninsula and Borneo and are a source of gas for Singapore.
Indonesia's exclusive economic zone (EEZ) extending from the Natunas overlaps with waters under the so-called nine-dotted line, a demarcation line used by China for its claims in the South China Sea, although Chinese officials have reportedly given Indonesia private assurances that it does not claim the islands or their EEZ.
Mr Supriyanto said Indonesian military planners are concerned that if conflict were to occur, there could be potential damage to Indonesia's offshore infrastructure, particularly oil and gas, in the Natunas, as well as the security of its shipping lanes through the South China Sea.
Some 70,000 people live in the 272-island Natuna archipelago, which lies an hour by air from Batam.
Concerns over China's claims in the area are not new. In 1996, Indonesia conducted a military exercise involving more than 19,000 troops, 50 warships and 40 combat aircraft in the Natunas, attracting a response from Beijing not to "complicate" the situation.
Several tense incidents and a recent review of Indonesia's strategic environment by the Indonesian Armed Forces have again raised the spectre of conflict in the area.
In late March, a Fisheries Ministry patrol boat briefly detained a Chinese fishing vessel off the Natunas, but was asked by a Chinese patrol boat to release the fishermen and their boat.
Indonesia's Navy is also organising a multilateral exercise off the Natunas early next year, and has invited navies from the ASEAN Defence Ministers' Meeting-Plus members, which include the United States and China, to take part in the drill which will focus on humanitarian relief.
Dr Kusnanto Anggoro of the Indonesian Defence University said Indonesia's defence and foreign ministries have been cautious, maintaining the position that Indonesia is not a claimant state in the territorial dispute.
However, military strategists, including the air force and navy chiefs, are more assertive and their concerns include skirmishes, blockades or even incursions into Indonesian territory, he added.
"For political officials, conflict in Natuna and the South China Sea is potential; for the military, these conflicts are existential," he said.
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