Talk:First Happy Time

German submarine crews referred to that time frame as the "Happy Time", tremendous successes and few losses. By winter of 1940/1941, however, the Royal Navy had installed radar on many of their escorts, robbing the wolf packs of their best weapon, surprise. Rates of sinkings were cut to less then half, and U-boat losses sharply increased. Also, the British discovered that their North Sea fishing trawlers made effective anti-submarine vessels when equipped with the necessary arms and electronics. They were not nearly as good as destroyers, of course, but they were easy to build in the United Kingdom and in Canada. The situation remained bad, but not disastrous.

The "Happy Time" did not last long. For one thing, Doenitz still did not have very many U-boats available. For another, the British started to install radar on their ships and gradually learned to fight at night. Using carefully coordinated air and ship operations, the Royal Navy was soon able to reestablish control over the convoy routes and, by January 1941, had reduced U-boat sinkings to 127,000 tons for that month.

From June to December 1940, German U-boats enjoyed what German sailors called the first "happy time". The new ports allowed them to stay at sea longer and attack more convoys. The British had so few escort warships that they could use only one or two to protect a convoy that might contain 30 merchant ships.

During this time, Admiral Karl Doenitz, commander of German U-boats, perfected his wolf pack tactics. He first used this technique against British convoy SC-7. Doenitz positioned five U-boats around the convoy. Surfacing at night, the U-boats attack from all directions—even from inside the convoy itself. The Germans sank 22 of the 34 merchant ships in SC-7. They had similar success against other convoys. By the end of 1940, Britain and its allies had lost 3,654,511 tons of merchant shipping.

The new base brought the U-boats some 450 miles closer, in sailing terms, to the enemy's vital sea lanes, almost doubling their effectiveness by extending their range of operation and time on patrol. Lorient was soon followed by Brest, Bordeaux, La Pallice, and St. Nazaire as operating bases. On August 17, recognizing an existing fact, Hitler proclaimed a total blockade on Britain.

U-boat skippers called this period the "Happy Time." With the convoys all but denuded of escorts and the torpedo crisis resolved by a switch from the erratic magnetic pistols to contact detonators, morale among the submarine crews soared in proportion to the tonnage they were sending to the bottom. Over the three-month period from July to September, 153 ships were sunk, for a monthly average of 252,926 tons, while only five submarines were lost. In October, 352,407 tons, or sixty-three ships, were sunk, including the forty-two-thousand-ton Empress of Canada, the only one of Britain's great liners sunk by a U-boat during the war. With sinking by the Luftwaffe, mines, surface raiders, and S-boats added, the toll exceeded Britain's capacity to replace the lost vessels.

Dönitz was still plagued, however, by the perennial shortage of boats, of which there were never more then fifteen at sea at a given time. As Jürgen Rohwer, a leading German historian of the Battle of the Atlantic has written, "[T]he high tonnage losses sustained by the British... are quite sufficient to give some idea of what could have been done... with effective long-range reconnaissance and more U-boats."

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The "gray wolves" took their toll not only from stragglers and vessels sailing independently, but from the poorly defended convoys as well. They were assisted by the ability of B-Dienst to read the British naval codes, which it had been doing since the crisis over the Italian invasion of Ethiopia. In fact, German intelligence was reading upward of 50 percent of the Royal Navy's signal traffic, which contained information about routings and timings of convoys and independent sailings. In a battlefield as large as the North Atlantic, any information about the location of enemy merchant shipping was of inestimable value. The Germans eavesdropped on this traffic until July 1943, when the British finally realized what was happening.

Very few specific anti-shipping operations were carried out in March and April, with the bulk of the available U-boat number being allocated to Operation Wesserübung, the invasion of Norway. U-boats were to patrol the entrances to Norway's fjords to prevent an Allied incursions. In the event, although many choice targets appeared before the waiting U-boats, torpedo problems meant that a substantial number of potential sinkings were lost.

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With the successful conclusion of the campaign in the west, the Kriegsmarine now had at its disposal a number of captured French naval installations which provided ideal locations for U-boat bases, giving them direct access to the Atlantic without having to pass through waters heavily patrolled by the Royal Navy. The considerable saving in journey time also gave the U-boats a much greater operational range, allowing them to patrol much further out into the Atlantic. Bases were also established in Norway giving direct access to the North Sea and faster access to the North Atlantic and the North-West Approaches.

...The period between summer and the end of 1940 became known to the Germans as the first 'Happy Time'. Between June and December 1940, over 360 enemy ships were sunk, accounting for almost 2,000,000 tons. U-boats were ranging well out into the Atlantic, well beyond the areas in which air cover could be provided, and were wreaking havoc amongst poorly protected convoys.

... [Details on specific convoy attacks]...

1941
In order to compensate for the still relatively slow rate of new builds coming from Germany's shipyards, in August 1940 the Italian Navy was invited to base some of its submarines in German-occupied French ports for operations into the Atlantic. These Italian submarines were never particularly successful. In just under three years, the 30 or so Italian submarines which had operated out of Bordeaux sank just 105 Allied vessels and lost 16 of their own number. The Italians were allocated their own area of responsibility in which German U-boats thereafter did not operate, Dönitz having no interest in seeing these boats come under his command.

The year began well. On the night of 23 February, Convoy OB288 was attacked by a pack consisting of four U-boats, U-69 (Metzler), U-73 (Rosenbaum), U-95 (Schreiber) and U-96 (Lehmann-Willenbrock), supported by the Italian submarine Bianchi. Eight ships totalling nearly 44,000 tons were sunk and a 9,000-tonner seriously damaged. However, this so called 'Happy Time' came to an abrupt end in March 1941 when, after a spell of remarkably low losses, three top aces, Prien Schepke and Kretschmer, were lost in convoy attacks. Prien in U-47 was lost on 7/9 March when attacking OB293 and both Schepke and Kretschmer on 16/17 March during attacks on HX112. Kretschmer and most of his crew were picked up and six survivors from U-100 were saved but Prien's U-47 was lost with all hands.

...[Use of aircraft to recon and attack]...

What was unknown to the Germans was that the British had beguon to take advantage of the installation of radar on their escort ships, this being one of the reasons the lost aces had been detected by the British during their attacks in March. Until now, U-boats running on the surface had avoided detection by Asdic and, being so small, were difficult to detect by sight. Dönitz, though aware of the decline in successes, was unaware that the British were now making use of radar.

Some Germans believed that the problem lay with British interception of German radio traffic, the enemy intercepting signals directing the U-baots towards their targets. ... The use of land-based high-frequency signal-detecting equipment in various locations, however, allowed triangulation on the chatter of signals between U-boats and BdU as the 'wolves' prepared to attack. Even without being breaking the codes, the Allies could detect the presence of U-boats in a particular area and route the convoy away from danger.

In the spring of 1941, U-boats which had been operating well out into the Atlantic were recalled to eastern waters when a number of tankers which broke out into the Atlantic with the battleship Bismarck and heavy cruiser Prinz Eugen were tracked down as a result of interception of German radio signals, and sunk. It was intended that, as well as servicing the warships, the tankers would also be used to refuel these U-boats.