A team of GUE divers set up a wreck diving expedition to the remote and rarely visited Bikini Atoll together with adventure diving company The Dirty Dozen last year.

The expedition was a part of a GUE mission and a personal passion stretching back almost two decades: to document the historical remains and traces of war. Even if the wrecks, capital warships, were sunk post-WWII during the nuclear experiments conducted, they still serve as some of the best historical monuments of that era in our history. 

The results and experiences during the expedition made it compelling to look forward and plan the next adventure following the same narrative. 

The target, the wrecks of Chuuk Lagoon came as naturally as our continued collaboration with The Dirty Dozen. We also chose to continue to use and rely upon the excellent liveaboard M/Y Truk Master with its world-class service and crew well-catered for technical diving — just the way we like it. 

Arriving at Chuuk 

Traveling into Chuuk is much easier and less of an adventure compared to getting to Bikini. A short jump from mainland Asia (the Philippines in my case) to Guam and then onwards on the island hopper to the next stop heading east, Chuuk Lagoon. 

Well, normally the flight path is pretty straightforward but, in my case, a tropical cyclone derailed my plans making me arrive a day later than planned. A bit of good advice based on lessons learned is to book the entire trip with United Airlines and not with different, non-code-sharing partner airlines as this makes situations with canceled flights challenging and expensive.

Approaching the islands of Chuuk from the air is impressive, the islands are beautiful and green with mountains and hills. You can see the artificial extension to the small island of Etten, where the Japanese army built its strategic air force base during the war. 

Looking down from the sky, it’s easy to imagine that this is exactly the same view the American torpedo and bomber pilots shared decades ago. The only thing missing is the Japanese ships at anchor in the bays, now turned into wrecks resting on the bottom of the sea.

A significant portion of the Imperial Japanese Navy’s combined fleet had anchorage at Truk. It became the key logistical and operational hub supporting Japan’s defenses in the Central and South Pacific.

It wasn’t until 1941 that the US entered an escalating WWII. Perhaps in part because they saw it as a European concern. The straw that broke the camel’s back, and American detachment, was Pearl Harbor. After entering the Pacific Theater, US reconnaissance flights discovered Truk Lagoon in 1943. They also discovered that this tiny outlying atoll was the largest Japanese naval base in the entire Pacific.

Operation Hailstone swiftly followed. This air raid decimated the Japanese Army’s ships and bases on Truk Lagoon, turning the area into a mass war grave.

After arriving here, the crew meets up and takes care of the short commute to the harbor followed by a short boat trip out to the liveaboard. A welcome drink and you’re all set for the dives of a lifetime. 

Setting Up for Tech Diving on the M/Y Truk Master 

Setting up for technical diving, in our case involving rebreathers, is easy even if at GUE we depend on a standardized configuration different to most. The divers bring their own key components, including special cylinder valves with a flexible manifold. The rest is supplied by the ship. 

Oxygen is produced onboard using an oxygen generator. An oxygen generator cannot produce 100% oxygen, only 92-96% and as such, special procedures are needed if diving a fully-closed rebreather in order to get the calibration of the oxygen sensors right among other things. 

Helium is available and required for the wrecks deeper than 30m/100 ft. We used 18/45 Trimix as our standard diluent mix. A clear head and lots of fun memories are what we’re looking for after all. My total setup time was less than 30 minutes thanks to the Truk Master’s excellent crew.

Diving the Wrecks of Chuuk 

The conditions both on the surface and underwater, are excellent in Chuuk lagoon. It rains quite a bit as the atoll is close to the equator but the reefs and islands provided excellent cover for winds, making waves something close to an urban legend. 

Underwater: picture yourself in a well-kept aquarium, no current, warm waters, and great visibility. What more can you ask for? Well, wrecks of course, and Chuuk lagoon does not fail to deliver those. 

There are more than 50 shipwrecks and a number of airplanes that can be explored. Normally, two wrecks are dived in one day as the distance separating them is short. The shipwrecks are almost all cargo ships used by the Japanese to supply and equip their army and air force bases on the island but there is one destroyer. 

Most sank fully loaded with supplies and war materials including tanks, cannons, trucks, and munitions. The preservation of the wrecks is good but you can see that time is taking its toll and collapses are to be expected during the next decade. One of the unique features of the Chuuk Lagoon wrecks is that they allow for extensive wreck penetrations. This is, of course, a potentially dangerous activity, but done right it’s a fantastic opportunity to travel back in time and view areas rarely viewed since the day of the sinking. 

My favorite penetrations involve the engine rooms where one can still study the gauges and telegraphs frozen in time. The diving is truly world-class if you are passionate about wreck diving and history.

Conclusions

After 10 days diving its time to depart, not because you want to, more that you have to, sadly. The diving in Chuuk is so good that another week would not have been sufficient to satisfy my appetite for adventure. 

Compared to the wrecks in Bikini Atoll, well, it’s like comparing apples and pears, both are delicious in their own way and the only choice you have is not to choose one, but to enjoy both. I enjoyed Chuuk and Bikini tremendously and will undoubtedly return to both for more adventures.

 Photos taken by Aron Arngrímsson.