Submarine Launch Debut in SE Asia By ALE
ALE completed the launch of the first ever submarine to be locally-assembled and launched in South East Asia. The KRI Alugoro (405) submarine was the final vessel to be commissioned as part of a $1.2 billion contract between Daewoo Shipbuilding and Marine Engineering (DSME) and the Indonesian Ministry of Defence for three diesel-electric 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. The complex operation required great accuracy and ALE’s offshore and shipyard experience enabled them to reduce the launch schedule.
One of the project’s challenges was working within the tidal windows available. ALE worked in both day and night shifts to provide the most time-efficient operation, enabling them to complete the manoeuvres more than four days ahead of schedule.
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. The experience and preparations of ALE’s team ensured that exact engineering calculations were completed in advance so that the manoeuvre could be performed safely and accurately.
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.
The manoeuvres were performed using 60 axle lines of SPMT, 16 150t capacity climbing jacks, 12 400t/hr capacity ballast pumps and four 8t capacity precision winches.
Following the successful completion of the Alugoro, DSME and the Indonesian Ministry of Defence signed a contract for a further three submarines.