Truk Lagoon served as the headquarters for the Japanese Combined Fleet during World War II. Japan had been mandated the islands of Micronesia following World War 1, and had exploited the natural geography of the lagoon to create a safe haven for their war fleet.

On February 17th 1944 American Fleet Task Force 58 launched ‘Operation Hailstone’ – an aerial attack on the runways, planes and ships anchored in the lagoon.

Operation HailstoneThe Japanese had sent their heavy cruisers, carriers and battleships out of the atoll on February 10th, having failed to shoot down 2 US reconnaissance planes on February 4th. Increased flight security patrols never saw the approaching US fleet, and the initial attack at dawn took the Japanese completely by surprise.

The Americans achieved their objectives within 36 hours. They first established air supremacy, then destroyed the runways and sank all of the major shipping within the lagoon.

Over 250 planes were damaged or destroyed and 220,000 tons of shipping was sunk – mainly merchant ships that were vital to supplying the Japanese fleet and occupied islands in the Pacific.

Continued attacks in April 1944 and later that year by B24s and B29s left over 40 wrecks lying at the bottom of the lagoon. Mostly merchant ships (Marus); there are also 2 destroyers, a submarine and 4 intact planes waiting to be explored by divers at depths ranging from 10-230ft/3-70m.


Truk Wreck Diving

Truk Stop Hotel and Truk Lagoon Dive Center
P.O. Box 546, Chuuk State,
Federated States of Micronesia 96942 
(691) 330-4232/4233/4285/4286 - 330-7990 – Reservations only | |