Sattakut Wreck, Koh Tao: Exploring a Thai Navy Patrol Boat

The HTMS Sattakut, a former Royal Thai Navy patrol boat, lies upright on the sandy bottom off Koh Tao, deliberately scuttled in 2011 to create an artificial reef. As you descend, the scale of this military vessel becomes clear, with its mast pointing towards the surface. The shallowest parts of the superstructure, including the bridge, are accessible around 18 metres, while the hull and stern extend down to 30 metres, offering a substantial profile for exploration.

Approaching the wreck, the outline of the ship materialises from the blue, its compact profile making navigation straightforward once you are familiar with the layout. The main deck provides numerous entry points for exploration, allowing you to trace the contours of the ship and appreciate its transformation. You can explore the hold or navigate past the bridge, now adorned with soft corals and sponges, steadily softening its metallic edges.

The structure of the Sattakut Wreck offers a varied topography. You can choose to loop around the exterior, observing the larger outlines and the schools of batfish and trevally that often hover above the wreck. Alternatively, venture into the safely accessible interior spaces, where sunlight penetrates just enough into certain sections, creating a play of light and shadow that enhances the exploration, revealing the detailed colonisation of anemones and sponges.

This artificial reef has become a focal point for the surrounding marine community. While exploring the wreck, you will encounter resident species such as groupers and snappers taking shelter within its structure. Moray eels are often found tucked into crevices, while lionfish and scorpionfish camouflage themselves against the ship's surfaces, demonstrating the ocean's remarkable ability to reclaim and regenerate.

The wreck's gun turrets and other parts of its superstructure remain largely intact, offering clear clues to its past life as a naval vessel. These features, now encrusted with marine growth, provide interesting photographic opportunities and a sense of history beneath the waves. The transformation from active service to a thriving underwater ecosystem is evident in the vibrant life that now calls the Sattakut home.

The HTMS Sattakut is typically dived by boat, located offshore from Koh Tao. The dive profile allows for a deep recreational wreck dive, with the stern reaching the maximum depth. The site's position means conditions can be variable, and understanding the layout before descending is key to a rewarding exploration of this well-known Koh Tao wreck.