Naval Weapons

Indonesia to receive ZOKA torpedo countermeasures for Nagapasa submarines

14 March 2019

An effector from Aselsan's ZOKA range of torpedo countermeasure jammers and decoys. Source: Aselsan

Key Points

  • Indonesia's Nagapasa-class submarines will be equipped with jammers and decoys from Turkish company Aselsan
  • The equipment will provide the vessels with protection and deception capabilities against hostile torpedoes

Turkish defence electronics company Aselsan is supplying its ZOKA range of acoustic torpedo countermeasure jammers and decoys for the Indonesian Navy's (Tentara Nasional Indonesia - Angkatan Laut, or TNI-AL's) submarines, a spokesperson from the company has confirmed with Jane's .

Aselsan declined to reveal the submarine type that the jammers and decoys would be deployed from, but subsequent verifications by Jane's with TNI-AL sources have established that the equipment will go on board the service's Nagapasa (Type 209/1400)-class diesel-electric boats (SSKs)

The ZOKA line of effectors consists of jammers and acoustic decoys that can operate in active, passive, and combined modes. The jammers emit noises that have been designed to saturate the acoustic operating frequencies of known torpedoes, thus masking its host submarine's movements from hostile munitions.

Meanwhile, its decoys can be programmed to simulate the acoustic and hydrographic characteristics of its host submarine, with the aim of deceiving and leading away torpedoes that may have locked on to the boat. These acoustic and hydrographic characteristics can be customised specifically to match those of the host submarine.

Indonesia acquired three Type 209/1400 boats from South Korean company Daewoo Shipbuilding and Marine Engineering (DSME) in 2011. The country has received two boats in the class, Nagapasa (403) and Ardadedali (404), and is awaiting launch of the final submarine, Alugoro (405).

The platform has an overall length of 61.2 m, an overall beam of 6.25 m, and a hull draught of 5.5 m. Each boat will be equipped with the ELAC KaleidoScope integrated submarine sonar suite from Wärtsilä ELAC Nautik.

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