German submarine U-48 was a Type VIIB U-boat of Nazi Germany's Kriegsmarine during World War II, and the most successful that was commissioned.
U-48 was built at the Germaniawerft in Kiel as yard number 583 during 1938 and 1939, being completed a few months before the outbreak of war in September 1939 and given to Kapitänleutnant (Kptlt.)
When war was declared, she was already in position in the North Atlantic, and received the news via radio, allowing her to operate immediately against Allied shipping.
The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) for use while surfaced, two AEG GU 460/8-276 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged.
Seven former members of the boat's crew earned the Knight's Cross of the Iron Cross during their military career: these were the commanders Herbert Schultze, Hans-Rudolf Rösing and Heinrich Bleichrodt, the first watch officer Reinhard Suhren, the second watch Otto Ites, the chief engineer Erich Zürn and the coxswain Horst Hofmann.
Following the sinking of Clan Chisholm, U-48 attacked the British steamer Rockpool with fire from her deck gun on 19 October at 1:32 pm.
Following the sinking of five enemy merchant ships for a total of 37,153 GRT as well as the engagement with Rockpool, U-48 returned to the safety of Kiel on 25 October 1939 after spending 22 days at sea.
The first ship to fall victim to the U-boat was the 6,336 GRT neutral Swedish motor tanker MT Gustaf E. Reuter.
Following the sinking of Gustaf E. Reuter, U-48 sank the British freighter Brandon on 8 December off the southern coast of Ireland.
[12] Germany learned that a troop convoy, including RMS Queen Mary and Mauretania were bringing 25,000 Australian soldiers to Britain.
Ireland sought an explanation from Germany "... steamships, the entire cargoes of which comprised grain for exclusive consumption in Éire were sunk by unidentified submarines ..."[14] U-48 was enjoying an extended patrol, thanks to the newly established refuelling facilities available at Trondheim in Norway.
In September, on her eighth patrol she shocked the world by sinking SS City of Benares, one of eight ships in six days from Convoys SC 3 and OB 213.
Heinrich Bleichrodt, the captain of the German submarine U-48, was accused of war crimes in the sinking of the SS City of Benares, but was ultimately acquitted.
As hundreds of survivors struggled in the water, the U-boat's powerful searchlight swept once over the chaotic scene before she left the area.
In total, 260 people,[15] including 100 children, 35 women, and 125 men, died in the disaster, which effectively ended the overseas evacuation programme.
It has been suggested that had the British openly declared that the ship was carrying evacuees, then the Germans would have taken pains not to sink it, recognising the potential for a propaganda crisis, which indeed occurred.
[16] Other historians have argued that the Germans would have attacked any large liners at the time, no matter what cargo was being carried or who was on the passenger list.
On her ninth and tenth patrols, U-48 claimed two and five victims respectively, but she was clearly becoming obsolete in the face of improving technology on both sides, despite a winter refit.
Her range and torpedo capacity were too small for the widening nature of the sea war, and she would be a risk to her crew and other U-boats if she continued much longer in the main battlefield of the North Atlantic.
U-48 returned to Kiel on 22 June 1941, where her crew disembarked and she was transferred to a training flotilla operating exclusively in the Baltic Sea.
In 1943 she was deemed unfit even for this reduced service, being laid up at Neustadt in Holstein with only a skeleton crew performing minor maintenance.