Black May (1943) facts for kids

Quick facts for kids Black May
Part of the Battle of the Atlantic
Depth charges exploding from the destroyer HMS Vanoc during an Atlantic Convoy in May 1943
Date 29 April – 24 May 1943 Location Atlantic Ocean Result Decisive Allied victory
Belligerents
United Kingdom	Germany
Commanders and leaders
Max Horton John Slessor	Karl Dönitz
Strength
Royal Navy Merchant navy	240 submarines
Casualties and losses
58 ships sunk	43 submarines destroyed 37 submarines damaged

Black May was a very important time during World War II. It happened in May 1943. This period was part of the Battle of the Atlantic. During Black May, German submarines, called U-boats, suffered huge losses. At the same time, fewer Allied ships were sunk. This event is seen as a major turning point in the Battle of the Atlantic. It helped the Allies win the war at sea.

A Type VIIC U-boat, U-995, at the German navy memorial at Laboe.

Why May 1943 Was a Turning Point

Before May 1943, the Battle of the Atlantic was very tough for the Allies. German U-boats were sinking many supply ships. These ships carried vital goods from America to Britain. Losing these ships made it hard for Britain to keep fighting. The period from March to May 1943 was a big crisis.

March: U-boat Successes

In March 1943, German U-boats were at their strongest. They attacked many convoys. Convoys are groups of merchant ships traveling together. They have warships protecting them. Some big battles happened around convoys like Convoy HX 229/SC 122. This was the largest convoy battle of the entire war.

The Allies lost 120 ships in March. This was about 693,000 tons of supplies. Most of these ships were lost in the Atlantic Ocean. The German U-boat force, called the U-Bootwaffe, lost 12 U-boats. A British Navy report said that Germany almost stopped all supplies from reaching Britain in March 1943.

April: A Short Break

April brought a small break from the intense fighting. The German U-boat force could not keep so many submarines in the Atlantic. Many U-boats had to go back to port for supplies. However, the U-boats that were still active kept attacking.

One shocking attack happened at the end of April. The U-boat U-515 attacked Convoy TS 37. Four oil tankers were sunk in just three minutes. Three more were lost in the next six hours.

In April, the Allies lost 64 ships. This was about 345,000 tons of supplies. The German U-boat force lost 15 U-boats. But the next month, May, would change everything. The Allies gained a big advantage. They kept this advantage for the rest of the war at sea.

May: The Tide Turns

May started with a fierce battle for Convoy ONS 5. Both sides lost many ships. The Allies lost 13 ships, but the Germans lost 6 U-boats. The Allied escort ships were getting much better at fighting U-boats.

The next three convoys that were attacked saw 7 Allied ships sink. But the Germans lost 7 U-boats. This was a big change. Then, convoy SC 130 was attacked. The Allies lost no ships at all. But the Germans lost 5 U-boats. Admiral Dönitz's son, Peter, was one of those lost on U-954.

Admiral Dönitz was the leader of the German U-boat force. He was shocked by these losses. He ordered his U-boats to leave the Atlantic. They needed to regroup and recover. The U-boats could not return in large numbers until autumn. They never got their advantage back.

In May, the Allies lost 58 ships. This was about 299,000 tons of supplies. Only 34 of these ships were lost in the Atlantic.

What "Black May" Meant

In May 1943, the German U-boat force was at its biggest. There were 240 U-boats ready for action. 118 of them were at sea. Yet, the number of Allied ships sunk kept going down. May 1943 also saw the biggest losses for U-boats up to that time. 41 U-boats were destroyed in May 1943. This was 25% of all active U-boats.

On May 24, 1943, Karl Dönitz ordered a temporary stop to the U-boat campaign. Most U-boats were pulled out of service. This was because of the terrible defeat they had suffered.

May saw fewer Allied losses and a huge increase in U-boat losses.

• 18 U-boats were lost in convoy battles in the Atlantic.
• 14 were lost to air patrols. Six of these were in the Bay of Biscay.
• Including losses from other areas, accidents, or other reasons, the German U-boat force lost 43 boats in May.

This was the worst month for U-boat losses in the war so far. It was almost three times worse than any previous month. More U-boats were lost in May 1943 than in all of 1941. It was also very bad because many experienced crews were lost. This included young officers who would have become future commanders.

Black May marked the start of a decline for the German U-boat force. They never fully recovered. Even with many efforts over the next two years, U-boats could not threaten Allied shipping like they used to.