Kapitänluetnant Hans-Heinrich Giessler entered the region just off Savannah Georgia on the 20th of September 1942 for a brief three-day incursion into the area. After reaching a point north of Jacksonville Florida he took U-455 due east across the Gulf Stream, then headed east-northeast out of the area roughly midway between the US coast and Bermuda. He sighted no Allied ships during this dip south from Cape Hatteras.
U-455 left Saint Nazaire on the 22nd of August to lay mines of Charleston, South Carolina. After investigating the waters of Newfoundland it moved south and completed its mine laying mission on the 18th of September. No ships were reported to have hit any of the mines laid by Giessler. After its incursion south of the Carolinas the boat called at the Gulf of Saint Lawrence and Cape Race, Canada – again without encountering Allied shipping. She arrived in Saint Nazaire on the 28th of October 1942.
Giessler was born in January 1911 and is over 100 years of age at the time of this writing. His career total was two ships sunk for 13,908 tons. Promoted to Korvettenkapitän in October of 1943, he earned the Iron Cross First Class. Over four patrols he served 185 days at sea, following which he was moved to the Torpedo Inspectorate. This was a crucially important role at the outset of the war, when many of the German torpedoes malfunctioned to the great frustration of many an accomplished U-boat skipper, with concomitant erosion of morale amongst entire crews. After a stint at the Ministry of Armaments and War Production, Giessler ended the war as First Watch Officer of the destroyer Z 20 Karl Galster.
SOURCES: Gudmundur Helgason, Rainer Kolbicz, www.uboat.net, 2011, Kenneth Wynn, U-boat Operations of the Second World War, Volume 1 and Volume 2, 1997