NV Ingenieurskantoor voor Scheepsbouw (Dutch: engineer-office for shipbuilding), usually contracted to IvS, was a Dutch dummy company set up by the Reichsmarineamt after World War I in order to maintain and develop German submarine know-how and to circumvent the limitations set by the Treaty of Versailles. The company designed several submarine types for paying countries, including the Soviet S class submarine and the prototypes for the German Type II submarine and the German Type VII submarine.

The company was a joint venture by the German shipyards AG Vulcan and the Krupp-owned Germaniawerft in Kiel and AG Weser in Bremen. Design work was carried out at the facilities of these companies in Germany.

Submarine sales

The company was funded by the German Navy. IvS first constructed two submarines for Spain, which were later sold to Turkey, both of which were launched in 1927 and were closely based on the Type UBIII of the Kaiserliche Marine. The contracts were worded in such a way that IvS personnel were involved with crew training and selection, and were allowed to take part in boat service trials. The Germans — who were, at the time, tightly restricted from using their submarines for themselves — thus gained a first-hand knowledge of how their new prototypes worked in practice.

Background information

At the time of IvS, the Germans were bound by a Treaty that they had signed and sworn to uphold as a result of the Armistice in 1918. This treaty, among its other terms, demanded that all of the German U-boats were destroyed or given to other nations. Thus the German Navy was left without a submarine capacity, and IvS was created to get around these restrictions. IvS ultimately provided the foundations of the massive, thousands-strong navy that Germany developed for use in World War II.

Later projects

In 1933 Germany established a school for training Unterseeboot crews, ironically under the title 'Anti-Submarine Defence School,' or in their tongue, Unterseebootsabwehrschule. This school was established in Kiel. This program involved provision for a small fleet of eight 500 ton submarines. This number was later doubled to 16.

Later, Germany developed plans for an actual navy. The projected designs for the boats that were to be the composition of this navy were referred to as 'Experimental Motor Boats'. Deutsche Werke in Kiel was elected to build the new submarines, and a new U-boat base was to be built at Kiel-Dietrichsdorf. There component materials were gathered surreptitiously, in preparation for the order to begin production. The program foresaw the following submarine types being built:

• 1934 – two large, 800 ton boats and two small 250-ton boats.
• 1935 – four small 250 ton boats
• 1936 – two large 800 ton boats and six 250 ton boats
• 1937 – two large 800 ton boats and six 250 ton boats

From there, more boats were constructed, and further on World War II itself began.

Battlecruisers

The IvS was also involved in designing plans for a Dutch project to build battlecruisers. Battlecruisers were deemed by some to be essential for the defence of the Dutch East Indies against possible Japanese expansion, especially so because the Royal Netherlands Navy lacked any large surface ships. The designs were heavily based on the German Gneisenau class and the final design was similar to the IvS design, because the Germans were expected to at least furnish the gun turrets for these ships, as constructing them was beyond Dutch capabilities. In the end, political disagreements slowed down the decision making process to April and none of the projected ships were laid down, as on May 10th 1940 the Germans invaded the Netherlands. Most likely, these ships would not have been completed even if they had been laid down sometime earlier.

References

• Dutch Export Submarines - Ingenieurskantoor voor Scheepsbouw
• Williamson, G Wolf Pack — The Story of the U-boat in World War II Osprey Publishing Ltd, 2005
• Teitler, Prof. Dr. G De strijd om de slagkruisers 1938–1940 De Bataafsche Leeuw, 1984