Editing Second Happy Time (section)

== Campaign ==
=== Opening moves ===
Immediately after war was declared on the United States, Dönitz began to implement Operation Paukenschlag (often translated as "drumbeat" or "drumroll",<ref>Fairbank White, David – ''Bitter Ocean – The dramatic story of the Battle of the Atlantic 1939–1945'', 2006, Headline Publishing Group {{ISBN|978-0-7553-1089-0}}, p. 146</ref> and literally as "[[timpani]] beat"). Only six of the twenty operational Type IX boats were available, and one of those six encountered mechanical trouble. This left just five long-range submarines for the opening moves of the campaign.<ref>Blair pp. 438–441</ref>

Loaded with the maximum possible amounts of fuel, food and ammunition, the first of the five Type IXs left [[Lorient]] in France on 18 December 1941, the others following over the next few days. Each carried sealed orders to be opened after passing 20°W, which directed them to different parts of the North American coast. No charts or sailing directions were available: ''[[Kapitänleutnant]]'' [[Reinhard Hardegen]] of {{GS|U-123|1940|2}}, for example, was provided with two tourist guides to New York, one of which contained a fold-out map of the harbor.<ref name=Gannon>Michael Gannon, ''Operation Drumbeat: the dramatic true story of Germany's first U-boat attacks along the American coast in World War II'', 1990, Harper and Row publishers, {{ISBN|0-06-016155-8}}</ref>{{rp|p137}}

Each U-boat made routine signals on exiting the [[Bay of Biscay]], which were picked up by the British [[Y service]] and plotted in [[Rodger Winn]]'s London Submarine Tracking Room, which were then able to follow the progress of the Type IXs across the Atlantic, and cable an early warning to the RCN. Working on the slimmest of evidence, Winn correctly deduced the target area and passed a detailed warning to Admiral King,<ref>Fairbank White, p. 147</ref> of a "heavy concentration of U-boats off the North American seaboard", including the five boats already on station and further groups that were in transit, 21 U-boats in all. Rear-Admiral [[Edwin T. Layton]] of the US Combined Operations and Intelligence Center then informed the responsible area commanders, but little or nothing else was done.<ref>Gannon 1990. Chapter 9</ref>

On 12 January 1942, Admiral Andrews was warned that "three or four U-boats" were about to commence operations against coastal shipping (in fact, there were indeed three),<ref>Gannon 1990. p. 212</ref> but he refused to institute a convoy system on the grounds that this would only provide the U-boats with more targets.

When {{GS|U-123|1940|2}} sank the 9,500-ton Norwegian tanker ''Norness'' within sight of [[Long Island]] in the early hours of 14 January, no warships were dispatched to investigate, allowing the ''U-123'' to sink the 6,700-ton British tanker ''Coimbra'' off [[Sandy Hook, New Jersey|Sandy Hook]] on the following night before proceeding south towards [[New Jersey]]. By this time there were 13 destroyers idle in New York Harbor, yet none were employed to deal with the immediate threat, and over the following nights ''U-123'' was presented with a succession of easy targets, most of them burning navigation lamps. At times, ''U-123'' was operating in coastal waters that were so shallow that they barely allowed it to conceal itself, let alone evade a depth charge attack.

=== Operation Drumbeat ===
The first attack wave, Operation Drumbeat, consisted of five Type IX boats. Their first victory upon arriving in the coastal region of North America was the Canadian freighter ''Cyclops'', sunk on 12 January off [[Nova Scotia]]. According to Robert Fisher, 26 more ships were sunk in the following nine days.<ref name="fisher_oil_34">Fisher (1993): p. 34</ref> The boats cruised along the coast, safely submerged through the day, and surfacing at night to pick off merchant vessels outlined against the lights of the cities.
* [[Reinhard Hardegen]] in {{GS|U-123|1940|2}} sank seven ships totalling 46,744 tons before he ran out of torpedoes and returned to base;
* [[Ernst Kals]] in {{GS|U-130|1941|2}} sank six ships of 36,988 tons;
* [[Robert-Richard Zapp]] in {{GS|U-66|1940|2}} sank five ships of 33,456 tons;
* [[Heinrich Bleichrodt]] in {{GS|U-109|1940|2}} sank four ships of 27,651 tons; and
* [[Ulrich Folkers]] on his first patrol in {{GS|U-125|1940|2}} sank one 6,666-ton vessel, the ''West Ivis'' (he was criticized by Dönitz for his poor performance, although he would later win the [[Knight's Cross of the Iron Cross]]).<ref name=Gannon/>{{rp|p. 271}}

When the first wave of U-boats returned to port through the early part of February, Dönitz wrote that each commander "had such an abundance of opportunities for attack that he could not by any means utilize them all: there were times when there were up to ten ships in sight, sailing with all lights burning on peacetime courses."

The RCN immediately organized coastal convoys when Drumbeat began despite the difficulty in finding escorts. 37 ships were lost in January and February, and only 11 in March and April. The RCN noted that by March and April the U-boats preferred hunting in US waters.<ref name="fisher_oil_35">Fisher (1993): p. 35</ref>

===U-boats in the Caribbean and the Gulf of Mexico===

{{See also|Operation Neuland|Battle of the St. Lawrence}}
[[File:Pennsylvania Sun.jpg|thumb|The tanker ''[[SS Pennsylvania Sun|Pennsylvania Sun]]'' torpedoed by {{GS|U-571||2}} on 15 July 1942 (was saved and returned to service in 1943).]]
The second wave of Type IX boats had arrived in North American waters, and the third wave ([[Operation Neuland]]) had reached its patrol area off the oil ports of the [[Caribbean]]. With such easy pickings and all Type IX boats already committed, Dönitz began sending shorter-range Type VIIs to the US East Coast as well. This required extraordinary measures: cramming every conceivable space with provisions, some even filling the fresh water tanks with diesel oil, and crossing the Atlantic at very low speed on a single engine to conserve fuel.

In the United States there was still no concerted response to the attacks. Responsibility rested with Admiral King, but he was preoccupied with the Japanese onslaught in the [[Pacific War|Pacific]]. Admiral Andrews' North Atlantic Coastal Frontier was expanded to take in [[South Carolina]] and renamed the [[Eastern Sea Frontier]] (ESF), but most of the ships and aircraft needed remained under the command of Admiral [[Royal E. Ingersoll]], Commander-in-Chief, [[United States Fleet Forces Command|Atlantic Fleet]], who was often at sea and unavailable to make decisions. Rodger Winn's detailed weekly U-boat situation reports from the Submarine Tracking Room in London were available but ignored.{{citation needed|date=January 2022}} By April, Allied forces along the US east coast included 80 small patrol ships in the USN [[Eastern Sea Frontier]], 160 US aircraft, 24 RN ASW trawlers, and one British [[RAF Coastal Command|Coastal Command]] squadron. By British and Canadian standards these were enough to begin convoying, but no comprehensive convoy system was implemented that month.<ref name="milner_2011_ch4_april_convoys"/> Instead, on 1 April the US implemented a partial convoy system where convoys moved along the coast in short hops, moving during daytime and stopping in protected anchorages during nights; these were slow and ineffective.<ref name="churchill_1950_122-123">Churchill (1950): pp. 122–123</ref><ref name="milner_2011_ch4_april_convoys"/>

Coastal forces were reinforced from the [[Mid-Ocean Escort Force]] (MOEF) before March. The US contribution to the MOEF fell to part of one   group. Five RCN corvettes were withdrawn to escort the new [[BX convoys|Boston-Halifax convoys]], the first convoys along the American seaboard.<ref name="milner_2011_ch4_moef">Milner (2011): chapter 4 ("Mid-ocean escort forces were further squeezed...")</ref> In April, a [[Royal Navy]] (RN) group redeployed to the Caribbean to defend tankers.<ref name="milner_2011_ch4_april_convoys">Milner (2011): chapter 4 ("In the spring of 1942, the possibility of future problems...")</ref> The RCN attempted to reinforce the MOEF by using training ships in supporting roles.<ref name="milner_2011_ch4_moef"/>

Allied tanker losses were alarming. Losses along the North American coast and in the Caribbean accounted for most of the 73 American tankers lost in the first half of 1942, and 22 British tankers lost in March; three out of the four largest Canadian tankers were also lost from February to May. In March, British Prime Minister [[Winston Churchill]] urged the USN to organize coastal convoys, to little effect. The next month, British tankers from the Caribbean avoided the US coast and sailed east to [[Freetown]] in [[Africa]],<ref name="fisher_oil_34"/> while between 16 and 29 April the US ordered US and Caribbean coastal waters closed to commercial tanker movement.<ref name="fisher_oil_35"/> On 26 April, the US agreed to allow Britain to redeploy a MOEF group to establish Caribbean convoys, but the US refused to start its own Caribbean convoys or to provide escorts.<ref name="fisher_oil_36">Fisher (1993): p. 36</ref>

Eastern Canada was dependent on imported oil from the Gulf of Mexico and the Caribbean.<ref name="fisher_oil_33">Fisher (1993): p. 33</ref> The crisis led to gasoline rationing on 1 April, and the potential consequences of the US-ordered halt to tanker movements were severe. On 28 April, the RCN started [[ad hoc]] convoys to bring Canadian and Canadian-charted tankers trapped in the US and the Caribbean back to Halifax. On 1 May, the Government of Canada insisted that Canadian tankers be escorted, leading the RCN to organize formal convoys to the Caribbean through US coastal waters.<ref name="fisher_oil_35"/> The RCN had only enough escorts to run convoys from Halifax to Trinidad (coded as TH); the loss of supply from other regional suppliers had to be accepted.<ref name="fisher_oil_36"/> In July, Trinidad was replaced by Aruba to accommodate British tanker movement. From May to August, fourteen convoys – including 76 tankers and 4 million barrels of oil – were run without a single ship lost. The convoys were discontinued in August with the advent of the US's comprehensive convoying system.<ref name="fisher_oil_37">Fisher (1993): p. 37</ref> Canada also began convoys between Nova Scotia and [[Quebec City]] in May.<ref name="milner_2011_ch4_overextension"/>

The search for Allied tankers and the support of {{GS|U-459||2}}, a Type XIV, pushed the U-boat offensive into the Gulf of Mexico.<ref name="fisher_oil_36"/> On 21 April, ''U-459'' was 600 miles north-west of Bermuda; it refuelled fourteen U-boats through 6 May, including Type VIIs, headed for the Gulf and the Caribbean. In May, they sank 115 ships (of which 101 were steaming independently), about half being in the Gulf, with half of that tonnage being tankers. In June, they sank 122 ships, of which 108 were sailing independently. The Gulf Sea Frontier, formed in early February, had barely any resources and was ineffective.<ref name="milner_2011_ch4_gulf">Milner (2011): chapter 4 ("As U-boat attacks spilled into the Gulf of Mexico...")</ref>

=== US convoys arrive ===
The first organized US coastal convoy sailed on 14 May 1942 from [[Hampton Roads]] for [[Key West]]; convoys eventually extended to Halifax.<ref name="churchill_1950_122-123"/> The US sought another  15 to 20 corvettes from Britain.<ref>Milner (2011): chapter 4 ("By mid-May, with both the British and Canadians operating...")</ref> By this time, two British escort groups were already in the Caribbean and the MOEF was under strain. Nonetheless, Britain and Canada responded to US requests by reducing the size of the remaining MOEF groups. The MOEF and the RCN had no further slack. The RCN struggled to meet its commitments even with 90% of its escort fleet being operational, as opposed to being used for training or being refitted;<ref name="milner_2011_ch4_overextension">Milner (2011): chapter 4 ("While Hecht was chasing convoys in the mid-ocean...")</ref> the negative effects of this over-extension would be felt well into 1943.<ref name="milner_2011_ch5_overextension">Milner (2011): chapter 5 ("By late summer 1942, the RCN was over extended...")</ref>  By comparison the RN escort fleet was merely two-thirds operational.<ref name="milner_2011_ch4_overextension"/> The weakening of MOEF contributed to difficulties in the mid-Atlantic in August.<ref name="milner_2011_ch4_moef"/>

The US convoy system effectively brought the crisis to an end. By early-July most U-boats only operated along the perimeter of the Caribbean. German attention returned to the mid-Atlantic.<ref>Milner (2011): chapter 4 ("By early July, four U-boats were still slaughtering...")</ref>