Symphonies of coral and steel: A week of deep and dark ghost fleet diving in Micronesia

Exploring the depths of Chuuk Lagoon, where wrecks of vessels sunk by US's Second World War Operation Hailstone lay

Diving among the wrecks of vessels sunk by the US Second World War attack Operation Hailstone in Chuuk Lagoon, Micronesia. Nic Ridley / The National

The Shinkoku Maru is probably the most beautiful oil tanker in the world. Her deck is a carpet of soft corals and sponges in vibrant – almost impossible – colours. Vast gorgonian sea fans waft slowly back and forth in the gentle and warm current. The tentacles of metre-wide anemones, in whites, oranges, greens and purples, offer symbiotic shelter to their resident clownfish.

Schools of silvery baitfish dart around the vast masts and kingposts that tower above her cargo holds. Pursued by predators, each rapid flash of their thousand-strong collective catches what little sunlight reaches down through the azure waters of Chuuk Lagoon, here in the Federated States of Micronesia.

The 150-metre Shinkoku is one of about 50 vessels of the Japanese Imperial Navy that were sunk in a little-known but pivotal battle of the Second World War, often referred to as Japan’s Pearl Harbour.

A brief history of Operation Hailstone

Before first light on February 17, 1944, a vast US carrier group in the western Pacific launched Operation Hailstone, the first of a series of attacks on Chuuk, then Japan’s largest naval base outside the home islands.

Over two days of aerial bombardment, the Americans would destroy hundreds of the infamous Zero fighters – lined-up on runways or in aerial dogfights – render airstrips unusable, raze barracks, mess halls, offices and fuel storage facilities, and ultimately cripple the enemy’s expansionist ambitions.

A primary aim was to sink much of Japan’s fleet, at anchor around the lagoon and its many islands, either delivering supplies or already under repair from previous run-ins with the Allies. However, Japan suspected an attack was imminent and was able to get most of its capital ships – destroyers and battleships – out of the lagoon before the onslaught.

What remained – tugs, tenders, oilers, personnel carriers, supply and cargo vessels – would be rich picking, and under heavy bombardment from bullets, bombs and torpedoes, they were sent – along with thousands of their officers and crew – to their final resting place.

Today, these ships are often in remarkable condition considering the nature of their demise and decades underwater. Recognised as the finest wreck diving in the world, over more than 80 years, they have become a symphony of steel and coral.

Diving monumental wrecks

Tropical rainstorms of the past two days have passed over Chuuk, and the skies above this tiny island state are cloudless and clear, the water warm and calm.

From our base on the comfortable 40-metre Odyssey liveaboard boat, within reach are the rusting hulks of a dozen vast sunken ships, a submarine with a particularly tragic and horrifying end, and even the remains of a Japanese “Betty” bomber that crashed into the sea on landing or failed to take flight on take off.

Shinkoku Maru lies upright at a maximum depth of 40 metres, and she is an early (and relatively easy) introduction to a week of deep, dark and dirty diving to this ghost fleet.

It is never less than exhilarating to descend through the water column as these colossal feats of heavy engineering, constructed as steam power made way for diesel, appear through the relative gloom.

The port side of her steel hull has been rent open in a torpedo strike and, wiggling clumsily through the gap, there are hard turns, sharp and quick ascents and descents, all the while being ever-careful fins don’t kick up decades of accumulated silt.

Moving slowly through the darkness, torches illuminate dials and gauges, walkways and steps, cylinder heads atop engines that once powered the drive shafts that turned the mighty propellers.

On other vessels, there are tool rooms – lathes, presses and drills still in place – and shelves stocked with the rotting remains of the myriad day-to-day items needed to keep these ships moving.

There are radio rooms – coils of antennae still visible – and galleys with woks sitting over what would have been open flames to cook for the crew their rations of rice and fish.

Many of the ships’ bridges have collapsed over the years, but where they survive, the telegraphs – “full ahead”, “full stop” – are often in situ.

Every ship contains marvels – heavy diggers and steamrollers that were never offloaded; cars for the officers, their windows blown out presumably by the change of pressure as the ship sank; and lots and lots of artillery.

There are the parts of Zero fighters, their component engine, fuselage and wings ready for reassembly that would never happen. There are periscopes stowed on the deck of a submarine tender, replacement propeller blades braced against bulkheads, and long-lance torpedoes, their warheads detached for safe transportation.

On the decks of these vessels, the anti-aircraft deck guns fore and aft still point upwards in what would be a failed attempt to fight off the aerial assault. Magazines of shells are often within reach.

Below decks are the soles of shoes, blue naval uniforms still folded for use, a box of matches lies in the sediment, and – incredibly, considering the years and the saltwater – a comic book. Medicine kits of tiny vials and ampules are housed in beautiful boxes. And countless empty bottles once filled with sake or beer litter vast open spaces.

As much as the massive engineering is awe-inspiring, it is these smaller items that remind every diver in Chuuk that these vessels are more than only the visible remains of a total war.

War graves

Since the 1970s, with the rediscovery of these ships by the famed explorer Jacques Cousteau, most of the remains of the thousands who died have been reclaimed by the Japanese and cremated in the Shinto tradition. But there are bones – these are war graves and should never be treated as anything less.

A high point of the week – and one of the reasons for my return after seven years – would be the San Francisco Maru, resting upright at a maximum depth of 67 metres.

Known as the Million-Dollar Wreck, her holds and tweendecks are filled with thousands of hemispherical beach mines, shipped to Chuuk in preparation for an amphibious Allied assault that never came.

Elsewhere, scores of 500lb and 1,000lb artillery shells are piled high alongside countless bullets, large stocks of torpedoes and depth charges. On her decks are three battle tanks, in place since she came to a thunderous rest on the seabed in 1944.

Like many other wrecks in Chuuk Lagoon, she is deeper than recreational dive limits allow – meaning long periods of decompression – but the effort is never less than the reward.

Today, the remnants of Operation Hailstone rest beneath the tranquil waters of Chuuk Lagoon, silent witnesses to a battle that shaped history. What was once a scene of destruction has become a sanctuary where corals and marine life thrive among the rusting hulls of war.

To dive here is to move through history, past shattered steel and lost artefacts, reminders of human ingenuity and the cost of war. Eight decades on, Chuuk Lagoon remains a paradox – a war grave and a place of endless renewal.

How to get there from the UAE

Travelling to Chuuk takes more than a little planning. After a direct flight from Dubai to Manila with Emirates airline, United Airlines flies to Guam, a US territory with visa requirements. From Guam, United has daily flights to Weno.