JR Potts, AUS 173d AB (Updated: 6/20/2016):
Despite the treaty, German engineers went along designing various weapon types using new technologies while always working to outmaneuver the Versailles Treaty restrictions (German was allowed a small standing army, armored cars, some small arms and no tanks, capital ships, aircraft or submarines). Such workarounds were managed by all branches of the German military - pilots trained on gliders and capital ships (such as the KMS Bismarck) were built heavier than the treaty allowed by false dimensions provided to the world by the German government.
However, some developments unintentionally adhered with treaty restrictions and led to creations like the "S-Boot" - essentially a scaled-down warship too small to be regulated by the Versailles treaty. Its sturdy design fulfilled a required operational role and the decision was to build boats of high quality over a mass production was the German way of waging war. The beginning of the torpedo boat program was a speedboat designed as a "submarine chaser". The German Naval Command began development in 1920 with series of trials using a variety of designs for boats suited for action in North Sea conditions. Hulls, commonly used for speedboats, were built with a surface-skimming qualities best suited for fast boats in calm waters. The North Sea required a different sort of boat design that allowed a robust hull to "plow" through heavy seas while not producing a highly visible plume of water at the stern.
In 1928, after many tests in the North Atlantic, German Naval Command settled on a rounded-bottom hull. They chose the hull of the "Oheka II", a luxury motor yacht built in 1927 by the German boatyard Luerssen. The hull measured 73 feet, 8 inches (22.5 meters) long and displaced 22.5 tons with a top speed of 34 knots making her the world's fastest boat of her class of the day. During sea trials, the boat ploughed through the water with plume as required, even when all three of her Maybach 550 horsepower engines were used. The rounded hull was made of wood planking to help reduce the weight and flattened at the stern area so the aft section area in water at high speeds was reduced, allowing more hydrodynamic lift when keeping the craft on a horizontal plane. In November of 1929, the German shipbuilder Luerssen was given a contract to build a boat to the new military-quality design. Two torpedo tubes were added along the forward castle and the engines upgraded for increased speed. It would become the first Kriegsmarine's standardized "Schnellboot" ("Fast Boat") and know in its abbreviated form as the "S-Boot" with the designation of "S-1". With improvements from the field filtered back to Luerssen, the basic design formed all future S-Boots built during World War 2 (1939-1945).
As the first S-Boots - eventually known to the Allies as "E-Boats" - were produced, additional improvements were being designed almost boat-to-boat. The second boat, S-2, was built with an advanced rudder assembly intended to reduce stern waves. This upgrade would help keep the boat in a horizontal attitude that increased the stability of the three propellers. In 1933, the boats produced needed to reserve the bow buoyancy so, starting with the construction of S-7, the hull as adjusted, preventing the boat from nosing deep into oncoming bow waves consistent with North Atlantic heavy weather. During the construction of S-20, the boat's superstructure was constructed so the boat's commander could stand on deck behind a wind and spray screen. This made communication difficult, requiring the commander to issue orders through a voice tube or by a seaman equipped with a headset intercom relaying information to the helmsman, navigator, and radio operator housed behind him in the wheel-house.
By 1940, when S-26 was constructed, a cockpit was added into the wheelhouse roof area. This addition allowed some shelter for the commander against the elements and increased visibility from a perched central location on the boat. An advantage of this change allowed the commander to speak orders directly to the crew in the wheelhouse without voice tubes. Starting with S-30 in 1939, several boats were built with a slightly smaller hull at 32.7 meters long and with the old style wheelhouses. By the time S-38 and her batch class was built, including S-130, an armored bridge had been added as well as additional anti-aircraft defensive armament: 2 x 20mm AA guns amidships plus 1 x 37mm AA gun mounted aft. In 1943, all S-Boots were reclassified as the "S-110" class.
On October 21st, 1943, the Johann Schlichting facility at Travemuende, Germany near Kiel, built S-130 (Hull No. 1030), codenamed "Rabe". She had incorporated all of the upgrades that had been tested and proved in-the-field to date. In November, S-130 was assigned to the 9th S-Boot Flotilla to help strengthen the German presence in the English Channel and North Atlantic. The 9th S-Boot Flotilla was stationed in Rotterdam from November 1943 until early 1944 to which the flotilla was then moved to Cherbourg situated on the Cotentin peninsula at Lower Normandy in northwest France. The flotilla's primary mission was to patrol the Channel and the North Atlantic and torpedo Allied shipping, depth charge submarines, lay mine fields and provide costal patrol duties.