Thai shipyard’s fast patrol craft have crew boat roots

MAY 14, 2014 — Thailand’s Marsun Shipyard has a long record as a builder of versatile , reliable crew boats. With three Cummins KTA38 M2 engines each rated at 1,350 HP turning fixed pitch propellers the aluminum-hulled vessels make speeds in excess of 24 knots with positive seakeeping abilities.

The concept of a military style patrol boat on a commercial hull platform was developed with the engineering departments of Marsun Shipyard and the Royal Thai Navy.

The patrol boat required a larger superstructure as well as some armament. To accommodate the additional weight, with increasing speed, the design team decided to increase the horsepower of the navy patrol version. This was accomplished by replacing the Cummins KTA38 M2 engines with three 1800-HP Cummins KTA50-M engines. The 36-meter hull maintained the same 7.6-meter beam and hull form.

The latest three modified version vessels, with 63-square-meters of clear deck space, retain much of the 36-m crew boat’s large 67-sq. m after deck. This gives the patrol boat the same 50-ton load capacity and allows the vessel to carry two 20-foot containers on the aft deck should the need arise. Modifications also give the vessel significant flexibility in operations, such as search and rescue capabilities, not found on most patrol vessels of this size.

The aft deck is designed with the capacity to mount surface-to-surface missiles. The forward deck has installed a 20 mm machine gun (a 30 mm machine gun is an option). Additional flexible space is designed-in to provide a control system command room in future.

The resulting patrol boat, with a total of 5400 reliable horsepower, achieves speeds in excess of 27 knots.

Although the larger engines require more fuel, navy specifications required less fuel capacity than the commercial vessel, which balanced the increase in engine weight. Overall the navy vessel has less weight and consumes less fuel than similar sized patrol boats while offering full functionality in sea state 5 conditions.