Shipwreck of heroic Greek sub found after 75 years

The shipwreck was identified by the hydrological-oceanographic vessel NAFTILOS of the Hydrographic Service on January 29, 2018 using multibeam sonar and sidescan sonar.

Its identification was made by the same ship from 4 to 6/5/2018 using submarine robotic cameras (ROVs) supplied by the diving crew of K. Thaktaridis.

Y-1 Katsonis (Greek: Y-1 Κατσώνης) was a Greek submarine active during the Second World War. Katsonis, together with her sister ship, Papanikolis, formed the first class of Greek submarines ordered after the First World War. The submarine was built at the Gironde Bordeaux shipyards between 1925–27, and commissioned into the Hellenic Navy on 8 June 1928. Her first captain was Cdr Κ. Arvanitis.

Under the command of Cdr Athanasios Spanidis, Katsonis participated in the 1940-41 Greco-Italian War, carrying out four war patrols, and sinking one vessel, the 531-ton Italian freighter Quinto, on 31 December 1940. After the German invasion of April 1941, together with the rest of the fleet, Katsonis fled to the Middle East, from where she would operate during the next years, with the British pennant number N 16. On 2 July 1942, she was damaged while exiting a dry dock at Port Said.

After overhaul, under the command of Cdr. Vasileios Laskos, she went on further three patrols in the Aegean. During these patrols, Katsonis ambushed and sank an Italian minelayer in the port of Gytheio on 2 April 1943, the Spanish 535-ton merchant vessel San Isidoro off Kythnos three days later, and the freighter Rigel near Skiathos on 29 May. On 14 September however, while trying to intercept a German troop transport, she was attacked and sunk by the German submarine chaser UJ-2101 (ex Greek mine sweeper Strymon, Cdr Kptlt. Friedrich Vollheim).

Katsonis was spotted on the surface and dived. After depthcharging she was forced to surface and continued fighting with her deck gun. Finally UJ-2101 rammed the submarine.

32 men of the crew, including Cdr Laskos, went down with her, and 15 were captured. Among them was Konstantinos Stamoulis, a survivor who was considered dead for decades. However, Lt Elias Tsoukalas, the ship's XO, and petty officers Antonios Antoniou and Anastasios Tsigros, managed to swim for 9 hours and reach Skiathos. There they hid and managed to return to Egypt and rejoin the Greek fleet.