Indonesia has commissioned the first domestic submarine assembled by itself, named KRI Alugoro
This was the second improved Chang Bogo class, also known as the Nagapasa class
The KRI Alugoro submarine project has been part of a defense cooperation program between South Korea and Indonesia since 2011
Chang Bogo itself is not a submarine developed by Korea, but only an improved version based on the German Type 209 submarine
Through two technology transfers, the Indonesian Navy finally mastered this submarine technology, with a new designation, the Nagapasa class
KRI Alugoro is classified as a diesel-electric submarine
The Nagapasa class submarine of the Indonesian Navy has a rather compact design, with a maximum displacement of only 1400 tons
It has a length of 61.2 metres (200 ft 9 in) with a beam of 6.25 metres (20 ft 6 in) and a hull draught of 5.5 metres (18 ft 1 in)
The Indonesian submarine uses four MTU 12V 493 diesel generators, providing a total of 5,000 horsepower
Its onboard fuel reserve makes it possible to cruise up to 20,000 km at 11 knots when Submerged
and can reach a maximum speed of 21.5 knots (39.8 km/h) when surfaced
The extremely smart design of the Nagapasa-class submarine allows it to hold enough food for more than 40 crew members
making continuous 50-day cruises at sea without resupply
Compared with conventional diesel-electric submarines, Nagapasa possesses the ability to dive deeply, up to 500 meters
At this depth, the Nagapasa class submarines will be completely "stealth"
Despite its compact size, Indonesia's Nagapasa-class submarines are equipped with 8 533mm torpedo tubes, carrying up to 14 Black Shark torpedoes
This is a modern torpedo manufactured by Italy since 2004
The torpedo has a length of 6.3 meters, maximum range up to 50 km
It is armed with a powerful explosive warhead, that could engulf the enemy's frigate with a single shot
As of 2019, Indonesia has planned to build a total of 6 new submarines of this class
Along with the two Cakra class submarines, the country will soon have the most powerful submarine force in Southeast Asia
According to previously published documents, the cost of owning three Nagapasa class submarines since 2011 up to $1.07 billion
By 2019, South Korea continues to sign an agreement to sell and transfer the complete technology for three more Nagapasa submarines to Indonesia
with a contract value of $1.02 billion, part of which would be converted into a loan