Last updated: May 19, 2026
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The Boston Navy Yard and Destroyer Escorts (DEs)
Bureau of Ships Collection in the U.S. National Archives. 19-N-53951
Since its establishment, the Charlestown Navy Yard has served the US Navy in wartime and peacetime. During World War II, the workers at the Navy Yard–called the Boston Navy Yard at the time–built many ships. Some of these ships supported Great Britain, the chief ally of the United States in the war. These ships included Destroyer Escorts, which helped hunt German submarines. Boston Navy Yard workers constructed dozens of DEs to help the Allies bring an end to the war.
In 1943, few if any programs were as important as that for building DEs…. Month after month during 1943, Boston led the Yards of the nation in the DE program. They were, in a sense, our baby. And the Yard can look back on a year's work well done, indeed.
Troubled Waters
At the start of World War II, German submarines, known as U-boats, tried to prevent supply ships from reaching Great Britain. The German U-boats sank these supply ships. These ships sailed across the Atlantic Ocean to bring goods to the people of Great Britain. Supplies included food, gasoline, military hardware and more. Most of these supplies came from the people of the US and Canada.
In 1940, German U-boats sank over 450 supply ships intended for Britain. These assaults became known as the Battle of the Atlantic. The battle lasted from 1939 to 1945. Workers at the Boston Navy Yard (BNY) began supporting Great Britain in this battle in 1940.
Early on in this conflict, US President Franklin D Roosevelt (FDR) wanted to help the British. By executive order in September 1940, FDR invoked the "Destroyer for Bases Agreement" between the US and Britain. The US sent about 50 US Navy destroyers left over from World War I (WWI) to the Royal [British] Navy to defend themselves against German U-boat attacks. Workers of the Boston Navy Yard refurbished eighteen of these WWI destroyers sent to Britain.
Even with these US Navy destroyers, the Royal Navy struggled to stop the German U-boats. A new approach had to be considered.
A New Ship
In the fall of 1940, US Navy officials travelled to England to meet with British authorities. Here, they discussed building a ship that would better fight the U-boats.
The British could not afford to build or buy these new ships. President Roosevelt proposed that the US build the ships and then lend them to the British. This was the provision of the "Lend-Lease Act" passed by the US Congress in March 1941. The US Navy Bureau of Ships worked with the American firm Gibbs & Cox to design an anti-submarine ship. The Bureau of Ships supervised the construction and repair of all US Navy vessels.
"Death on subs!" National Archives.
In 1941, American and British officials continued working on plans for this new ship. In that year, U-boats sank another 430 supply ships intended for Great Britain. These attacks destroyed many tons of supplies and killed numerous crew members aboard these supply ships.
On December 11, 1941, the US officially declared war against Germany and Japan after the attack on Pearl Harbor. In the following year, the US Navy doubled the number of workers at the Boston Navy Yard. These workers began building a variety of vessels for both the US and British navies, including the new anti-submarine ships.
US Navy ship designers called the new anti-submarine vessel a "Destroyer Escort" or "DE." The new DEs would protect ships bringing aid to Great Britain. A DE was smaller than a regular destroyer. Naval experts hoped that it would take workers less than half the time and half the cost to build a DE rather than a regular destroyer.
The DEs maneuvered more easily than a regular destroyer, allowing them to more effectively attack U-boats. Additionally, DEs moved more slowly than regular destroyers. Because of their slower speeds, DEs required less fuel and could travel further than regular destroyers. Protecting supply ships from German submarines did not require fast ships.
The US Navy contracted with 16 shipyards, both government-run and private, to build DEs. This contract included the Boston Navy Yard.
The DE Classes
Before work could begin on construction, designs had to be solidified. The US Navy created six classes, or types, of DEs. The six classes resembled each other, differing mainly by the type of engine each had. The shortage of all engine types in the US Navy in WWII influenced which DE class workers built. Of the total 563 DEs that the US Navy built during the war, about half of these DEs had steam turbine engines and the other half had diesel engines.
All DEs shared common features. These features included explosive devices against submarines, called depth charges and hedgehogs. Depth charges were huge barrel-size bombs. Sailors dropped or threw from the stern of a DE to try to destroy submarines in the waters below. Hedgehogs were another explosive weapon used to attack submarines. The hedgehog had up to 24 projectiles. They fired together in a circular pattern intended to sink a sub. Hedgehogs were more accurate in hitting subs than depth charges. Most DEs also had torpedoes.
These ships also had detection devices to hunt submarines. Radar, ASDIC (an early version of sonar), and High-Frequency Direction Finding (HFDF) assisted in this mission.
DEs differed by the guns they carried. For an all-purpose gun, most DEs had a 3” gun, others had a 5” gun. For anti-aircraft weapons, all DEs had 20mm guns and some also had 40mm guns.
The length of DEs built by the Navy ranged from 289 feet long to 306 feet long. DEs were at least 70 feet shorter than regular destroyers.
Boston Navy Yard Gets Busy
Boston National Historical Park, BOSTS 11807-2
Historian Frederick Black called the Boston Navy Yard "the pacesetter" for constructing DEs at shipyards.[1] In May 1943, BNY became the first among 16 shipyards to build four DEs in one month. BNY workers built 46 DEs in 1943, setting a record.
As Boston workers gained experience, they were able to build a DE in less than four months. To work faster, they prefabricated large sections of DEs. This prefabrication of ship sections shortened the time needed to build a ship.
Workers at the Boston Navy Yard built DEs on Shipways #1 and #2 and Dry Dock #5. Shipways #1 and #2 were open platforms. Here, workers slid completed ships off the shipways into the ocean. Managers of the Boston Navy Yard built Dry Dock #5 in 1942 specifically to construct DEs. Workers built two DEs at the same time in both Shipways #1 and #2 and four DEs at once in Dry Dock #5.
Boston National Historical Park, BOSTS 14958.
In 1943, the Chief of the Bureau of Ships, Rear Admiral E.L. Cochrane, praised the Boston Navy Yard workers. The BNY workers had built destroyers and destroyer escorts at record speed. He said that the BNY effort "merits the highest commendation and ranks as one of the outstanding feats of shipbuilding history."[2] Workers here in Boston built more DEs in the first 11 months of 1943 than any other yard, public or private.
Workers at the BNY received other praise. Starting in February 1942, the BNY regularly received the coveted Army-Navy "E" pennant award from the War and Navy Departments. The award recognized outstanding war production. Less than 5% of the 85,000 defense plants doing work for the US armed forces received the "E" pennant awards. BNY earned these awards regularly throughout WWII.
Workers at the BNY built a total of 62 DEs during WWII. 31 went to the US Navy. Navy officials named these ships in honor of Navy and Marine military heroes from earlier in the war. BNY workers also built 31 DEs for the Royal Navy. Tthe British named these ships for British heroes of the Napoleonic era. Shipbuilders of the Boston Navy Yard built 52 Evarts Class DEs and 10 John C. Butler Class DEs.
DEs to the Rescue
In 1942, German U-boats destroyed the most supply ships intended for Britain in WWII. They sank more than 1,000 ships carrying over 5 million tons of goods. In April 1943, American-built Destroyer Escorts sailed into the Atlantic Ocean for the first time. They began protecting supply ships bound for the UK. The first of these DEs came from the Boston Navy Yard. By the end of 1943, DEs helped reduce U-boat attacks by more than half. By 1945, the last year of the war, the Allies lost only 54 supply ships to U-boats.
DEs may have played a role in destroying 800 of the 1,100 U-boats the German navy directed during WWII.[3]
DEs and their sailors also served in the Pacific Campaign of WWII. DEs in the Pacific protected supply ships as they did in the Atlantic. These supply ships mostly carried fuel and ammunition to US armed forces. Sailors on DEs hunted Japanese submarines and protected other US Navy ships from Japanese kamikaze attacks. The Navy converted some DEs into troop transports in 1944. These DE transports were especially critical in Pacific battles. About 25% of DEs built in the BNY served in the Pacific Campaign.
A Special DE
One of the most well-known DEs built in the BNY during WWII was USS Mason, DE 529. It entered service in March 1944 and escorted over five Atlantic Ocean supply-ship convoys. USS Mason became notable not so much for its exploits but rather its crew.
U.S. Navy Photograph 80-G-218861, National Archives and Records Administration, Still Pictures Division.
USS Mason was one of two WWII ships in the US Navy which had a crew that mostly consisted of African American sailors. African American leaders and Eleanor Roosevelt advocated for the deployment of this ship. The US Navy had been denying combat roles to its Black sailors during WWII. The federal government maintained a segregated military force throughout WWII. After the war, President Truman desegregated the US armed forces in 1948 by executive order.
In 1994, President Clinton awarded commendations to 67 surviving sailors of USS Mason. He commended the sailors for their courageous DE convoy duty and for their trail-blazing military service.
Fair Winds, Following Seas
World War II sailors highly praised the 563 DEs built by the US Navy. Most DEs survived attacks and went undamaged during WWII. After the war, many DEs were decommissioned and eventually scrapped. The Navy sent some DEs to foreign countries after the war. Workers at Boston Navy Yard refurbished eight DEs and sent six of them to Greece. The British returned the DEs loaned to them by the US for the war.
The last two DEs built in the Boston Navy Yard became specialized radar picket ships in 1955 and served until 1960. Today, the US Navy no longer builds Destroyer Escort ships.
Boston National Historical Park, BOSTS 14588-1601.
Workers at the Boston Navy Yard built the first DEs and set the pace for building DEs quickly. Managers of other shipyards that built DEs were likely inspired by the BNY workers’ reputation for building ships. The US Navy and the workers at the Boston Navy Yard helped the Allies defeat Germany and Japan in WWII. They did this because they rapidly built and deployed DEs in the Atlantic and Pacific Oceans, especially in 1943.
Footnotes
[1] Frederick R. Black, Charlestown Navy Yard 1890-1973 (Boston, Boston National Historical Park, National Park Service, U.S. Department of the Interior, 1988).
[2] E.L. Cochrane, Rear Admiral USN, Chief of Bureau of Ships quoted in Boston Navy Yard News, January 6, 1944. Vol 9, No. 1, Unpublished.
[3] "U-boat Fates," Uboat.net, accessed May 9, 2026. U-boat losses 1939-1945.
Sources
"Battle of the Atlantic-Its Development 1939-1942." Naval History. Accessed April 24, 2026. Battle of Atlantic.
"Battle of the Atlantic Statistics." US Merchant Marine. Accessed April 10, 2026. Battle of the Atlantic Statistics.
Black, Frederick, R. Charlestown Navy Yard 1890-1973. Boston, Boston National Historical Park, National Park Service, U.S. Department of the Interior, 1988.
Carlson, Stephen P. Charlestown Navy Yard Historic Resource Study, Vol 1-3. Boston, MA: Division of Cultural Resources, Boston National Historical Park, National Park Service, U.S. Department of the Interior, 2010.
Carlson, Stephen, P. "Ships Built by the Charlestown Navy Yard." Accessed April 8, 2026. NPS.gov Ships Built by the Charlestown Navy Yard.
Cora, Paul B. "Holding the Line on the High Seas." Warfare History Network. Accessed April 12, 2026. Holding the Line on the High Seas - Warfare History Network.
"Destroyer Escorts." Destroyer History. Accessed April 8, 2026. DestroyerHistory.org
"Destroyers Lost or Damaged During World War II." The National Association of Destroyer Veterans. Accessed April 16, 2026. Destroyers Lost or Damaged During World War II - Tin Can Sailors.
Fitzgerald, Clare. "USS Mason (DE-529): Eleanor’s Folly’ Helped Break Racial Barriers in the US Navy." War History Online. Accessed April 9, 2026. USS Mason (DE-529): 'Eleanor's Folly' Helped Break Racial Barriers in the US Navy
Halsey, Ashley, Jr. Lieutenant. "Those Not So Little Ships--The DEs." US Naval Institute. September 1943. Vol. 69/9/487. Accessed April 8, 2026. US Naval Institute Magazine.
"History of Destroyer Escorts." USS Slater. Accessed April 8, 2025. USS Slater Website
History of the Boston Navy Yard (Industrial Department): The history of the Boston NavyYard from January 1939 to 30 June 1945. July 1945. Unpublished.
Krechel, Sara. "Warfare Centers, NSWC Dahlgren Division." Naval Sea Systems Command. Accessed April 16, 2026. NSWCDD Blog - Dahlgren's E Award.
Lewis, David PMP. "The Industrial Integration of Design and Production in the WWII U.S. Emergency Destroyer Escort Shipbuilding Program." LinkedIn. Accessed April 8, 2026.
Mansfield, George, O.Q. Historical Review: Boston Naval Shipyard, formerly Boston NavyYard 1938-1957. Boston Naval Shipyard, 1957.
McCarton, Matthew and Bill Garzke. "Navy-After-Next Contingency Producible Corvette (CPC) Emergency Production Historical Study." Naval Sea Systems Command. S&FAC Report No. 9070-03-C5 NAVSEA 05D -134 - DTD NOV 19, 2004. Navy-After-Next Contingency Producible Corvette (CPC): Emergency Production Historical Study.
Schick, Joshua. "USS Mason: First in its Class." The National WWII Museum. Accessed April 8, 2026. National WW2 Museum USS MASON.
Stewart, George. “Post-World War II Destroyer Escorts.” Naval Historical Foundation. Accessed April 9, 2026. Post-World War II Destroyer Escorts | Naval Historical Foundation
Williamson, Gordon. U-boats vs Destroyer Escorts: The Battle of the Atlantic. Oxford UK, Osprey Publishing, 2007.
"Yard's 'E' Renewal 5th Star Honors.” Boston Navy Yard News. March 24, 1945, Vol. 10 No. 6. Unpublished.