Mapping Debris Fields of Lost US Ships from the 1944 Battle of Leyte Gulf Midshipman 1/C Buinauskas, USN, Class of 2020; Advisor: Professor Peter L

Mapping Debris Fields of Lost US Ships from the 1944 Battle of Leyte Gulf Midshipman 1/C Buinauskas, USN, Class of 2020; Advisor: Professor Peter L. Guth Introduction Results In the aftermath of the Battle of Leyte Gulf, the Allied Forces lost one After creating the debris fields, I determined that the USS St. Lo sunk light carrier, two escort carriers, two destroyers, and one destroyer-escort. facing southwestward, since the ship stayed relatively intact and the Some of these ships’ wrecks were more intact, which made the ship bow of the wreck faced southwest at approximately 225° (Figure 1). whose wreck it was easily identifiable. An example of this is the The two furthest pieces of debris had a distance of 273.9 meters Casablanca-class Escort Carrier USS St. Lo, which was identifiable by a between them, with the furthest piece hitting the sea floor at 98.07 clear “63” painted on the hull. The other wrecks, however, consisted meters away from the ship. According to the general plans, the St. Lo merely of scrap metal and ship parts, none of which alone were enough was about 19 meters wide, so the debris field spread a significant to lead to identification. In these circumstances, the location, size, and distance from the ship itself (U.S. Naval Repair Base San Diego, parts of the wreck were all considered in identifying the ship it belonged 2019a). I then determined that the USS Johnston sunk facing to. This was the case for a pile of scrap metal off the coast of Samar, northwestward at about 300°, since the bow of the ship sank relatively which was recently identified as the Fletcher-class Destroyer USS Figure 1. Aerial view of the general plans for the U.S. Casablanca-class carrier, overlaid northwestward of the rest of the debris, while other debris correlating Johnston (Werner, 2019). Another destroyer, the USS Hoel, was sunk in onto its debris field. with further-astern-related parts of the ship sank southeast relative to the same general location as the USS Johnston, which made identifying the bow (Figure 2). Unlike the St. Lo, the debris field was scattered, the wreck difficult. However, the location of the wreck being in the since the destroyer was demolished into many pieces, making the ship southern part of the area where the battle took place was what led the difficult to identify. The two furthest pieces of debris had a distance of wreck to be claimed as that of the USS Johnston (Werner, 2019). Using 401.2 meters between them; which, from a ship whose original beam videos I obtained of the wrecks, I was able to locate the final resting was about 11.5 meters wide, makes for a much larger range than the places of the two ships and determine the orientations in which they hit debris field of the St. Lo (U.S. Naval Repair Base San Diego, 2019b). bottom, in order to present how the wreck looks today – after spending the last 75 years on the sea floor, more than 4000 meters beneath the Discussion ocean’s surface. Given that the USS St. Lo was sunk by a kamikaze pilot, it makes sense that the majority of the ship remained together. Taking a hit from a Background Japanese plane would sink a carrier, but would not create enough force The Battle of Leyte Gulf took place from 23-26 October, 1944. Preceding to tear the ship into a multitude of pieces. Because of the manner in Figure 2. Aerial view of the general plans for the U.S. Fletcher-class destroyer, overlaid the battle, the Japanese Imperial Navy’s First Mobile Fleet launched onto its debris field. which the St. Lo was sunk, there were larger pieces of debris scattered Operation Shō in order to counter the impending Allied landings in the around the wreck, but not in the same quantity that a ship sunk by Philippines (NHHC, 2019a). This operation consisted of sending the hundreds of 5 and 14-inch rounds would incur, like what happened to majority of Japan’s remaining ships in a desperate attempt to inflict the USS Johnston (New World Encyclopedia, 2019). Since the USS damage upon the US forces. The ploy successfully drew Admiral William Johnston was sunk by enemy fire, the ship was torn into pieces. While F. Halsey’s Third Fleet away from the Leyte Gulf area, which exposed sinking, the pieces would have floated away from the wreck, and the northern flank of Vice Admiral Thomas C. Kincaid’s Seventh Fleet landed on the seafloor further distances away. Since the debris pieces (NHHC, 2019a). This left the most northwesterly task unit, Rear Admiral were smaller, they were more susceptible to ocean currents, which Clifton A. F. Sprague’s TG 77.4.3, call sign “Taffy 3,” to battle four could have moved the debris even further from their initial landing Japanese battleships, six heavy cruisers, two light cruisers, and 11 sites, creating a larger debris field. destroyers – a battle later deemed the Battle off Samar, the largest naval battle of World War II (NHHC, 2019b). Taffy 3 was comprised of six Conclusion escort carriers, three destroyers, and four destroyer escorts, of which The Battle off Samar was not a victory for the 113 of those who lost were no match for the Japanese. Of these, the destroyers USS Johnston their lives fighting for the USS Johnston, or the 186 of those doing the and USS Hoel, and carriers USS Gambier Bay and USS St. Lo were sunk. same for the USS St. Lo (Werner, 2019). However, being able to Figure 3. Debris field of the USS St. Lo. identify our lost ships and honor those lives lost in the pursuit of our Methodology country’s liberty might be enough to take a small step towards We used the MICRODEM GIS program (Guth, 2009) for most of the lessening the defeat. Due to our generation’s ability to utilize analysis, supplemented with Google Earth (Google, 2015). Professor technology such as the RV Petrel’s imaging systems, we were able to Guth obtained videos of the two shipwrecks taken by the Research Vessel dive over 4000 meters deep in the Leyte Gulf to identify two lost Petrel from the Naval History and Heritage Command. I went through World War II ships, the carrier USS St. Lo and what is likely to be the the videos, and screenshotted significant images of the ships and their destroyer USS. Johnston. We were then able to pinpoint the locations debris. I then created a database with each video the image was of the wrecks and their respective debris, and create a database screenshotted from, the time in the video of the screenshot, the latitude, detailing each debris piece. Using the GIS program, we were able to longitude, altitude, and heading of each screenshot, and a description of map the debris fields and showcase the exact locations of the pieces. what I thought the image might be. The database allowed me to create a We now know exactly where our lost ships are, the orientation in map of the debris fields with points at the locations of each image. Then, which they sank, and have pictures of what the debris looks like to I created icons for each image, and exported both debris field maps to date, over 75 years after the conclusion of the Battle of Leyte Gulf. In Google Earth. After that, I found plans for the 1944 Casablanca-class order to protect and respect the wreck sites as war graves, the exact carrier and Fletcher-class destroyer, and overlaid the plans on top of the locations have not yet been released to the public, as to prevent grave debris fields in Google Earth. I sized the plans to-scale, and rotated them plundering of any magnitude. in the orientation of the wrecks based on my identification of key Figure 4. Debris field of the USS Johnston. Acknowledgements: We used the freeware GIS MICRODEM (Guth, 2009) for the majority of this study. features. Finally, I created a layer in Google Earth to overlay the icons, to The Naval History and Heritage Command provided the videos of the shipwreck, which were video- create a complete image of both debris fields (Figures 3&4). graphed by the Research Vessel Petrel.