Truk Odyssey Scuba Diving, Dec. 8-13, 2014

From Dec. 7-14 Liz and I were scuba diving in Truk Lagoon on the Truk Odyssey liveaboard dive boat.

Truk is considered the premier wreck diving destination in the world due to 50+ Japanese ships being sunk there by the Operation Hailstone air attack Feb. 17-18, 1944.
Since the ships were inside the 45-mile circumference lagoon during the attack, they are typically within recreational dive depths of 130 feet. We dived one destroyer and a Betty Bomber plane, but the other 11 wrecks were merchant ships, though often with military cargo.

The first recon flight in January 1944 showed the Battleship Yamato and 2 aircraft carriers in Truk, but the Japanese withdrew most warships to Palau before the attack. Truk was isolated and never invaded during the year and a half after the attack, so many of the remaining Japanese starved.

These islands, now named Chuuk, are part of the Federated States of Micronesia and are not much of a general tourist destination. It's very poor and it's considered unsafe for tourists to wander far from the few hotels. This, plus the advanced nature of the diving, influenced us to choose liveaboard vs. a land-based tour. The Chuukese had a rough time, living on the island the Japanese chose for their premier mid-Pacific naval and air base. Even after the war the lagoon was so polluted from the wreckage that fishing was depressed for decades. Local Kimiuo Aisek, who lived through the attack at age 17, initiated dive tourism in the 1970's as described here: ... story.html .

Liz gave me a GoPro for my birthday, which I promptly flooded on the first try in Yap the previous week. We hope to get some pics from one of the other divers on the trip, but I've seen this scenario before, and usually if it doesn't happen at the end of the trip by copying files, it's not that likely weeks later by mail. In the meantime I've excerpted a few shots from divemaster Mike Gerken's video.

Mike is an acclaimed underwater photographer and a leading authority on the Truk wrecks. However , he's also the boat captain with many responsibilities and thus films only a few of the dives. Mike was our guide for the last day dive of the San Francisco Maru. All of the other Odyssey guides were excellent also, which is very important when you're inside wrecks at 90+ feet multiple times over a week of diving.

Tractor balanced on crossbeam in the Hoki Maru

Liz deep inside the Hoki Maru

I'm following Liz around to the front of these trucks

Some artifacts have been placed on deck for easier viewing, like the lantern and dishes here.

Some of the decks were overgrown with varied corals.

Two of the wrecks had intact engine rooms we could explore. These pics from the Kensho Maru.

One advantage of the liveaboard is getting more than one dive on some of the wrecks. Liz had a slow-to-equalize delayed start on the first Kensho Maru dive. So on the second one I led her into the Kensho engine room she missed the first dive and then out that skylight above. With ships 350 - 500 feet long there are many things to see, and time can be limited at depth per dive. Above the Kensho deck:

I'm entering the Shinkoku Maru engine room here

Shinkoku diesel engine

There was a turtle outside the Shinkoku.

We had one non-wreck dive. They set up a frozen bait ball to attract sharks on the outer reef.

It took 20 minutes for the sharks to break up the frozen bait. The larger Whitetip circled the area.

Ships that sank upright tended to preserve better. Engine rooms have mostly collapsed on other ships. The Rio de Janiero Maru was on its port side.

The ship's deck is the vertical wall behind the bubbles. I'm still inside, barely visible above Liz

Here I'm checking out a case of beer bottles

Here's the Rio de Janiero Maru's starboard propeller.

With much of the diving below 90 feet, we took long safety stops at shallower depths. In many case there were masts rising up to a depth of 20-30 feet with lush coral growth.

A large anemone on this one

An extra tank of air was hung 15 feet below the boat in case anyone ran out.

On the last day we had the option to dive the San Francisco Maru. This wreck is famous for 3 tanks on the deck and holds full of munitions. Liz and by one tank with another in the right background

The deck is at 160 feet, so we could only be down there 8-10 minutes with close to half an hour of decompression coming back up.

socal wrote: 160ft is deep. I've been down to about 90 ft.

160 feet is beyond normal recreational dive limits. We were allowed to be on the deck of the San Francisco Maru for only 8-10 minutes. My dive watch flashed that decompression stops were required. We rose gradually to about 50 feet, spent ~20 minutes rising from there to about 20 feet. Even after the watch stopped flashing we remained at 15 feet for another 7 minutes for an added margin of safety.

You do not want to get decompression illness in Truk as local medical facilities are minimal and the nearest recompression chamber is in Guam.

My guess is that even with advanced certification and ~150 dives experience, Liz and I were among the least experienced divers on the Odyssey and that may have been the reason that the captain Mike Gerken guided us on this dive. Mike and some of the other divers used air at depth and then switched to 50% oxygen for the decompression stops at <50 feet. Liz and I have Nitrox certification (we were on 24% oxygen for the San Francisco Maru and 30% on the rest of the dives) but have never had a course on gas switching during dives. With the gas switch you could spend more time at 160 feet but I don't know how much more.

In Bali in 2012 Richard and I got to 165 feet with a divemaster to see a mola mola. This was not the plan and my dive watch was new and I didn't know how to read its decompression instructions. But I knew enough to spend some time at 60 feet and then I used all my air at 15 feet before getting out of the water. The dive watch would have "locked me out" of any more diving for 24 hours if my decompression had been inadequate on the mola mola dive.