She started making headlines well before she was built and continued to be followed in the press until her end. She was the largest submarine in the world (at the time) and she was launched on November 18, 1929. The French submarine Surcouf, 360 feet long and displacing 3,000 tons on the surface, 4,300 submerged. She carried 10 torpedo tubes, two 8" guns and a seaplane. A truly revolutionary design, but like all submarines of that size and that time, turned out to be a disappointment.

The great naval powers have always been fascinated with bigger weapons, but for a diesel electric type submarine there is definitely an optimum size. The Americans built the Argonaut, the British the X-1 and the Japanese would later build the I-400 class, all proved unwieldy, slow and clumsy. It seems that only the Germans learned early on that this type craft has a maximum useful size limit. The famous Type VII and Type IX boats were the most successful submarines ever built. However the American fleet submarines; Gato, Balao and Tench class submarines were the best, most durable diesel electric boats ever built.

All these submarines were about the same size and displacement, the differences of course were their machinery, weapons and electronics. All of them were quick on the surface and more importantly, maneuverable underwater. The large submarines failed in both speed and maneuverability, this made them more dangerous to their crews than to the enemy for the most part. The dreams of their designers never materialized and the shortcomings usually caused their loss. Nevertheless a number of large, strange underwater craft were designed in the inter-war years, by all sides.

Surcouf, with her large guns forward of the conning tower, made her a strange looking craft indeed, but she must have been cursed by Poseidon himself. Her launch went flawlessly, but her performance was less than satisfactory. In May of 1940 she escaped France ahead of the Nazi occupation and fled to England. While at Plymouth the British boarded her in an attempt to keep her from joining with the Vichy Government, two of Surcouf's crew were killed as were two British officers, including the commanding officer of HMS Thames.

Surcouf later went to the USA for a refit and was involved in the "liberation" of Saint Pierre and Miquelon islands. When she was dispatched to the Pacific rumors that the giant submarine would try to take Martinique began to fly, but there is no evidence that this was ever the mission for Surcouf. She was en route to the Pacific theatre when on Feb. 18, 1942 she was run down and sunk by the freighter SS Thompson Lykes, there were no survivors.

© 2014 Michael W. Pocock
MaritimeQuest.com

Portrait of Surcouf by Michel Guyot.