South Korea has successfully developed a combat system for its envisioned 3,000-ton attack submarine, the state arms agency announced Tuesday.

The country plans to build a total of nine 3,000-ton submarines with its own technology in the Chang Bogo III project and the first is scheduled to be launched next year, according to the Defense Acquisition Program Administration.

They will replace the Navy's nine aging 1,200-ton subs in stages. It also has nine 1,800-ton diesel-electric ones.

The DAPA, in partnership with the Agency for Defense Development and contract firms, has pushed for the indigenous development of a related combat system regarded as the "brain" of submarine armaments.

"Recently, it received a provisional assessment from the Ministry of National Defense to be suitable for combat use," said the DAPA.

In June, the sonar system, considered the "ears" of a submarine, won the same evaluation from the ministry.

"It means that the development of both the combat and sonar systems, which are core arms elements for the 3,000-ton Chang Bogo III submarines, has entered the completion phase," the DAPA said.

The systems will go through final tests after being installed on the submarine to be built.

"With the success of indigenously developing the combat and sonar systems, cost and time are expected to be cut greatly for the operation and maintenance of the submarines," said Rear Adm. Chung Il-sik, head of the DAPA's next-generation submarine project team. (Yonhap)