SM UB-53 [SEP] vessel class
SM UB-53
SM "UB-53" was a German Type UB III submarine or U-boat in the Imperial German Navy () during World War I. She was commissioned into the Pola Flotilla of the German Imperial Navy on 21 August 1917 as SM "UB-53".
She operated as part of the Pola Flotilla based in Cattaro. "UB-53" was sunk by mines of the Otranto Barrage on 3 August 1918 at in the Otranto Strait, 10 crew members died.SS Athenia (1914). On 7 April 1918
with a deck-mounted machine gun. "UB-13" was broken into sections and shipped by rail to Antwerp for reassembly. She was launched in March 1915 and commissioned as SM "UB-13" in April.
"UB-13" spent her entire career in the Flanders Flotilla and sank 11 merchant ships, about half of them British fishing vessels. In March 1916, "UB-13" was responsible for sinking the Dutch ocean liner , raising the ire of the Dutch public. "Tubantia" was the largest neutral vessel sunk during