Penetrating the HTMS Sattakut

Want to explore a sunken warship? Here’s your chance. The US Navy built and commissioned the HTMS Sattakut in 1944 for deployment in WWII. After an interesting history of service, decommission, and sale, the ship eventually came into the hands of Thai Royal Navy and the King of Thailand, and now, recreational SCUBA divers visiting Koh Tao get huge benefits, including wreck penetration. 

Diving the HTMS Sattakut

Recognizing the opportunity to create a premier dive site for SCUBA divers on Koh Tao, in 2011, the Thai Navy and several sponsors purposefully submerged the HTMS Sattakut at 30 meters right off the house reef of Sairee Beach. At 48 meters long and 7 meters wide, she’s the perfect training ship for wannabe wreck divers, well within the limiting depth of recreational diving. How lucky for the divers of Koh Tao and me! I was fortunate to dive on the Sattakut often during my PADI Divemaster training in 2015 and to become a PADI Wreck Specialty Instructor in 2016.

This week, as part of continued training with PADI Course Director Andrea Warren at Crystal Dive, I supervised a training dive on the HTMS Sattakut with two soon-to-be PADI Wreck Specialty Instructors. With me watching behind (and shooting from a head cam), the two new instructors practiced laying in and out line in this wreck penetration. The guys did great, as we’d practiced on land quite a bit, and we pulled it off within the limits of our dive plan. The most interesting thing about this dive was the low-light conditions and turbidity (all those particles floating about).


Watching this video of the HTMS Sattakut instructor training dive, do you notice how we descend into a thermocline while navigating to the wreck? You may also notice a moment upon arriving at the wreck when the first diver gets his bearings at the pilot house. Finally, do you notice how the turbidity of the water creates an interesting mood upon penetration as the light bounces off the particles back at the camera?

All of these factors create an interesting, or even an eerie, mood that may disorientate inexperienced divers. To more experienced divers, they’re things that we note and make adjustment for as a buddy team. While the video here may look frightening to some new divers, more experienced divers come to love wreck diving and shun other forms of diving. What do you think? Want to take the course? Let us know.

What’s so Special About a Wreck Dive?

Diving on a wreck demands more of us. Wreck diving creates special conditions and hazards that must be considered, like the overhead environment, low-light conditions, and sharp, corroding surfaces that may cut a diver or collapse at any moment. The corridors within a wreck should be studied in advance, (if possible), by researching the ship’s history and build. A well-prepared buddy team spends a few days researching the wreck and mapping it over several dives before they make a planned penetration. Research should include a history of the wreck as well as looking into any existing laws and regulations that may govern dives on the wreck.

If you’re lucky, other divers will provide accessible training tools created through prior research and publications online. Thai SCUBA provides extensive material in English for divers wanting to penetrate wrecks in Thai coastal waters. Wrecks like the HTMS Sattakut are well documented online by many sources, providing divers with extensive tools to use prior to a planned penetration. And of course, no penetration should occur by divers who are not certified wreck specialty divers by a credible certification agency. The PADI Wreck Specialty course equips divers with everything they need to safely make planned penetrations with a buddy within the limit of 40 meters from the surface and while staying within the light zone.

Why Require the Wreck Specialty Course?

Divers take unnecessary risks by entering into overhead environments without proper training. Sadly, some of these divers haven’t made it out of wrecks or caves because they hadn’t planned their dives properly for air consumption and limits of penetration distance. In many cases rescue divers find poor planning and negligence to be the cause. It’s said, “you never know what you don’t know,” and in the case of diving, everything you need to know, instructors make available through easy courses. Why not take advantage of the HTMS Sattakut and forego the unnecessary risks?