Editing Second Happy Time (section)

=== 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.