In the context of the establishment of the Federal German Navy there was a great demand for vessels for practice training of personal during the first years, among those also submarines. As a first measure, two U-boats Type XXIII of the Kriegsmarine, that were sunk in 1945, were salvaged and repaired to such an extent that they could be commissioned as Type 240 as early as 1957 for practice training purposes. Ex Kriegsmarine U 2365 became U Hai of the Federal German Navy und ex U 2367 became U Hecht. U Hai was lost due to an accident on 14th of September 1966 in the Northsea, with 19 deaths and only 1 survivor, and was scrapped in 1968 after it was lifted. U Hecht was decommissioned in 1968 and scrapped as well.
Apart from the Type XXIII U-boats of the Kriegsmarine an additional large “Electro-U-boat” of Kriegsmarine Type XXI was commissioned by the new Federal German Navy. After its salvage in 1957 and its restoration, former U 2540 was operated by the Federal German Navy as training U-boat Type 240 between 1960 and 1982 under the name Wilhelm Bauer, since 1970 with a civilian complement. In 1983, she was decommissioned and given to the German Maritime Museum at Bremerhaven as an exhibit ship, where is has been seen by more than 3 Millions visitors since.
These U-boats were the first post-war new construction, with first developments starting in 1955. Some 12 units were to be built for the new Federal German Navy, optimized for operations in the Baltic Sea but still observing the arms control restrictions by the WEU not to exceed 350 to displacement surfaced. In 1961, construction of the first U-boats of the new type started and on 23rd of March 1962 U 1 was commissioned as first unit. U 2 followed on 05 May 1962. U 3 was given on loan to the Norwegian Navy between 10th of July 1962 and 16 June 1964, to sail there under the name Kobben for test and trials. Already U-boat No. 4 of the series planned had to accommodate significant changes in design taking on the new name of Type 205. Therefore, Type 201 did never comprise more than 3 units. Soon after the commissioning of the first U-boats severe faults were found at the innovative amagnetic steel of the outer hull, all three U-boats of Type 201 and further 5 units under construction of Type 205 were effected by that. After new amagnetic and corrosion-resistant steel was developed, U 1 and U 2 were modified and factually converted to Type 205 U-boats. In contrast, U 3, after it was returned from Norway, was operated non-modified as Training U-boat by the Federal German Navy until 1967, to be decommissioned afterwards.
The first plans of the new Navy included also the construction of some 12 smaller submarines, just 100 t displacement and an armament of 2 torpedoes, crew 8-10 men. These plans, however, were given up. Nevertheless, this type of submarine was developed to its final stages to comprise 3 units. 2 Trial U-boats were constructed in 1965 as Type 202 and on 14th of October 1965 Hans Techel was commissioned, on 06th of April 1966 Friedrich Schürer, construction of the 3rd U-boat was abandoned. These small U-boats had a crew of 6 men, 2 bow torpedo tubes and a low range of just 400 nmi with 10 kn driven by mere 350 HP. The U-boats demonstrated to be largely unsuitable for the intended scale of operations and were consequently decommissioned, both on 15 December 1966. Further developments were stopped at the same time.
During the planning and construction of the 12 U-boats Type 201 additional military requirements resulted in introducing a new name: Type 205, starting with the 4th U-boat of the building program underway. In contrast to Type 201 this type had an improved range, was a bit longer and had a slightly greater underwater displacement. In this context, a German request of 19th October 1962 at the WEU to raise the limitation of the displacement surfaced from 350 t to 450 t was granted, thereby sanctioning the slight passing of the limits given retroactively since the initial design did not meet the limit in the first place. This type starts with U 4 and a total of 9 U-boats were commissioned until 1969. The former U-boats Type 201 U 1 and U 2 were re-commissioned in 1966/67 after their major modification. In the end, Type 205 plus modified Type 205A comprised a total of 11 U-boats. U 1 was modified another time in 1988 to function as Trial U-boat for an air independent propulsion system. After the U-boats Type 206 were running in starting in 1973 the 5 remaining U-boats Type 205 (U 4, U 5, U 6, U 7 and U 8) were decommissioned.
Besides the modification, however, in fact new construction, of U 1 and U 2 between 1964 and 1966 to Type 205A specifications, 4 more U-boats of Type 205 (U 9, U 10, U 11, U 12) were improved to Type 205A between 1967 and 1969. Major improvements saw a slight increase in propulsion power, a re-designed Combat Information Centre and changes to the rudder. 5 U-boats of Type 205A (U 1, U 2, U 9, U 10 and U 11) were decommissioned between 1991 and 1993 and 2005 the last (U 12) of the formerly 11 U-boats Type 205/ 205A was retired. During their last period of service U 11 and U 12 were used as Test- and Trial U-boats.
On the basis of Type 205 new U-boats Type 206 were designed, which were 5 Meters longer, had a more powerful propulsion and extended range, as well as several other improvements over the U-boats build so far. Between 1973 and 1975 all 18 U-boats were commissioned in rapid sequence (U 13 on 19 April 1973 to U 30 on 19 March 1975). Following the operational improvement of 12 U-boats to Type 206A and the structural adaptations of the Navy after 1990 the remaining 6 U-boats Type 206 (U 13, U 14, U 19, U 20, U 21 and U 27) were decommissioned between 1997 and 1998.
Between 1988 and 1991 some 12 U-boats of Type 206 were operationally improved, inter alia a more powerful sonar, a new weapon control system for new torpedoes and a new periscope were installed. Being re-named Type 206A the modified U-boats (U 15 to U 18 and U 22 to U 30) formed the backbone of the submarine force of the Navy of the Federal Republic of Germany for a long time. Structural changes of the Navy as a result of the repeated scaling down of the size of the Bundeswehr after 1990 and the commissioning of the new U-boats Type 212A led to the reduction also of the U-boats Type 206A: Between 2004 and 2008 some 6 U-boats of this type were decommissioned (U 22, U 25, U 26, U 28, U 29 and U 30) , leaving the submarine flotilla of the Navy of the Federal Republic of Germany after 2008, together with the 4 U-boats Type 212A, at a strength of 10 units. On the 10th of June 2010 another decision was made to decommssion the remaining 6 U-boats Type 206A (U 15, U 16, U 17, U 18, U 23 and U 24).
Throughout 20 years after the launching of the last U-boat of Type 206 (U 30 on 04 April 1974) not a single submarine was build for the German Navy on German shipyards. Only the successful exports of submarines maintained the necessary capabilities. Not before 1987 plannings started for a completely new type of submarine, with air independent propulsion and considerably greater displacement than the submarines build so far. After successful trials with a new fuel cell system were carried out in 1988/89 onboard the converted U 1, construction order was placed for U-boats of Type 212A. The launch of the first U-boat, U 31, occurred on 20 March 2003, almost 28 years after the launch of the last of the series of U-boats of Type 206. With a hull design of favourable hydrodynamic shape, the new U-boats have a displacement of about 1.800 t submerged, have a crew of 27 (lately also female crewmembers) and a range of about 8.000 nmi at 8 kn, generated by their 4.200 HP air independent propulsion system, reach some 12 kn surfaced and up to 20 kn submerged, can operated safely down to 400 m deep and up to two weeks submerged (Type 206A managed to operate submerged up to 96 hours), and have 6 bow torpedo tubes for new wire guided heavy torpedoes. On 19th of October 2005 the two first U-boats (U 31 and U 32) were commissioned, on 13 June 2006 the third (U 33) and on 03 May 2007 the fourth (U 34) and last of the first batch of Type 212A submarines. Two more U-boats (U 35 and U 36) are under construction and scheduled for delivery in 2011 and 2012.