The M36-class patrol boats have been built by Marsun Company and are intended to serve the maritime patrol requirements of the Royal Thai Navy (RTN). The patrol boat can conduct a range of missions such as marine law enforcement, prevention of onshore or sea infiltrations and protection of shipping, search-and-rescue (SAR) missions and perform security operations for VIPs. The RTN currently operates a fleet of five M36 patrol vessels. Marsun laid the keels for the fourth and fifth M36-class vessels in June 2018 at its shipbuilding facility in Samut Prakan. 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. A patrol boat required a larger superstructure as well as some armament.
The class has overall length of 36 m, an overall beam of 7.6 m, and a hull draught of 1.7 m. It can attain a top speed of 27 kt, a standard range of 1,200 n miles at 12 kt, and accommodate a crew of 28. The M36-class patrol boats feature a mono-hull design with an integrating Aluminium hull and superstructure. The mono-hull design ensures the vessel’s high-performance and durability and is designed to offer extended service-life, even when operating in harsh weather conditions. The on-board fuel tank has a maximum fuel-carrying capacity of 34m³, while the vessel’s freshwater storage unit has a capacity of 7.6m³. In addition, the vessel offers a clear deck space of 63m² and accommodates a rigid-hulled inflatable boat (RHIB) at the rear deck area.
The M36 class patrol boats are powered by three Cummins KTA50-M engines, which each have a rated power output of 1,800 brake horsepower (bhp) at 1,900rpm. The resulting patrol boat 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. Auxiliary power systems on-board the patrol boat include two Cummins generators with a capacity to produce 112kWe of power each, as well as a three-phase AC power supply with a rated voltage of 380V at 50Hz and a single-phase 220V AC electric power supply operating at 50Hz. 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.
The forward bow deck is fitted with a single 20mm or 30mm machine gun. Its duel-fed cannon is assisted by a hydraulic device for rearming process, while two large boxes are stationed near the weapon station to house the cartridges. The M36-class vessels also feature two weapon mounts that can hold machine guns, which are able to fire 0.50-calibre (12.7mm) ammunition. The aft deck is capable of accommodating a pedestal-mounted surface-to-surface missiles and surface-to-air missile (SAM) system, allowing it to launch weapons such as Mistral SAMs. Additional flexible space is designed-in to provide a control system command room in future.