Documenting the First Three U.S. Aircraft Discovered in Truk Lagoon from Operation Hailstone (February, 1944)

Abstract Operation Hailstone, conducted on 17–18 February 1944, was a major battle between the United States fast carrier Task Force 58 against the forward operating naval base of the Imperial Japanese Navy at Truk Lagoon (modern-day Chuuk, Federated States of Micronesia). The battle saw devastating losses for the Japanese forces with over 4500 casualties, over 50 ships sunk and over 250 planes lost. Because the battle losses were so skewed, the United States losses are often understated or overlooked. Thirty-five U.S. service members were killed with as many as 17 aircraft lost, with further losses in subsequent attacks. Despite Truk Lagoon’s status as a premier dive destination since the mid-1960s, no American aircraft from this battle or subsequent raids on the Chuuk atoll have been located in the lagoon prior to the surveys reported here. In an effort to locate remains of American service members still missing in action from this battle (35 from Operation Hailstone and as many as 225 from subsequent attacks and bombing missions on the atoll), we applied both knowledge from historical archives and advanced underwater robotics to survey large sections of the lagoon for these lost aircraft. With over 75 km 2 surveyed, we located three American aircraft lost in Truk Lagoon during Operation Hailstone; two Douglas SBD-5 Dauntlesses and either a Grumman TBF or TBM Avenger. Here, we document these sites and link each to the detailed historical accounts of their loss. Each of these aircraft is known to have been crewed by service members still missing in action. This work underscores the American losses during Operation Hailstone and sheds light on the more than 72,000 service members still missing in action from World War II.