The KRI Alugoro (405) submarine was recently the final vessel to be commissioned as part of a $1.2 billion contract between South Korean shipbuilder Daewoo Shipbuilding and Marine Engineering (DSME) and the Indonesian Ministry of Defence for three diesel-electric submarines.

Following completion of the Alugoro, DSME and the Indonesian Ministry of Defence signed a contract for a further three submarines.

The KASEL 3 submarine, weighing 1,331t, had to be loaded-out onto a barge, towed to a dock, transferred to a floating dock, then a pontoon, before eventually being launched.

As explained, one of the project’s challenges was working within the tidal windows available.

ALE first carried out a weighing of the submarine and then began the transportation from the fabrication shop to the quayside using 60 axle lines of SPMT.

There, a barge had been prepared with ALE providing the mooring, winches and ballasting. The 61m submarine was loaded-out and sea-fastened to the deck.

The vessel was towed to a graving dock where it was positioned and set down. ALE then transferred the submarine onto a floating dock where it was secured.

The floating dock was floated with ballasting and towed out of the graving dock before it was repositioned. Along with a pontoon, it was then set down in the graving dock.

During the pontoon floatation, ALE had to work with extreme accuracy as there was only 20cm of freeboard available.

ALE transferred the submarine onto the pontoon, again securing it with sea fastening.

The pontoon was floated with ballasting and towed away from its supports, then set down on the ground of the graving dock where full ballasting of all tanks was performed.

The submarine was jacked-down using climbing jacks and the dock was filled to allow the floatation of the submarine.

Once complete, the submarine was towed from the graving dock and officially launched at a designated pier.