The last of the first type, Z16 Friedrich Eckholdt, was commissioned in July 1938. By then, the construction of the first six of the improved Type 36 or Roeder-class ships, Z17 to Z22, was well underway at the Deschimag yard, which by now stood at the forefront of Zerstörer construction. The new vessels had an altered bridge design and smaller funnels to reduce top weight, while the forecastle was given improved sheer through a ‘Clipper’ bow, lengthening it by 2 metres (6 feet). Seaworthiness was only marginally enhanced, though. The first of the Type 36 Zerstörer, Z17 Diether von Roeder, was commissioned in August 1938, the last, Z22 Anton Schmitt, three weeks after the war had commenced.23 Improved destroyer types would be laid down in 1938, 1939 and 1940 but none of these would be operational until well after the fall of France.
Zerstörer Z11 Bernd von Arnim manoeuvring off Wesermünde with some of her sisters. These were powerful and efficient ships, but quickly lost stability and hence fighting efficiency as the seas became rough. (Author’s collection)
In spite of their inferior sea-keeping abilities, the Zerstörer were potentially fierce adversaries, with five 12.7-cm guns in single mountings, four semi-automatic 37-mm A/A guns in twin mountings amidships and six single-mounted 20-mm guns. Two quadruple torpedo mountings and four depth-charge throwers added to the sting. Unlike most British destroyers, the German ones were equipped for mine-laying from the start. On either side, from amidships aft to the stern, rails were built into the deck on which between sixty and seventy-six mines, depending on type, could be carried without any modifications to the ships. The carrying of a full mine-load did not improve the stability of the Zerstörer, though, requiring reasonably benign sea conditions. None of the early German destroyers carried radar, but they had very effective passive underwater sound-receiving devices along both sides as well as active echo-sounders (S-Gerät) to detect submarines.
The main fire-control of the 12.7-cm guns was located on the bridge, above which the main 4-metre rangefinder was positioned. The secondary fire-control station was located just behind the aft funnel. The 12.7-cm shell had a maximum range of 17,400 metres (19,000 yards), and a trained crew could get away fifteen to eighteen shells per minute – in calm seas. The magazines stored only 120 rounds per gun, however, and the stocks were rapidly reduced during combat. Surprisingly, this does not seem to have worried anybody as no modifications were made.24 The foremost 12.7-cm gun was badly affected by breaking waves, even in moderate seas, and could not be operated under adverse conditions.
High-pressure super-heated steam turbines developing 70,000 horsepower gave a maximum speed in excess of 38 knots. These plants were supposedly at the peak of German technology, but, extremely complicated and pressed into service virtually untested, they would never prove their merit. Many of the early destroyers had a notoriously poor serviceability record. On 18 November 1939, for example, of twenty-two destroyers in commission, only five were operational. The remaining seventeen were in harbour with some defect or other, mainly engine related. Range of the Zerstörer was given as 4,400 miles at 19 knots, but trials showed that it was necessary to maintain 30 per cent of the fuel for ballast, due to the stability issue, which reduced the effective range considerably. At the outbreak of the war, the Zerstörer had been assigned to flotillas for tactical exercises but many were still undergoing trials and working up.25
Fast, potent small ships were an attractive alternative for the German Navy bound by restrictions and, after half a dozen test boats, the first S-boats – S7 to S13 – were commissioned in 1934/35.26 These were sleek, wooden, diesel boats displacing 86 tons and armed with two torpedoes and one 20-mm machine gun aft. Development stalled for some time, but enthusiastic officers finally pushed through the approval for further boats and the slightly bigger S18 to S25 were commissioned between July 1938 and December 1939. These had 6,000 horsepower diesel engines, which gave them a top speed of almost 40 knots, and with good sea-keeping qualities they soon became popular with their crews. War conditions quickly showed the vulnerability of their complicated engines, though, and an inadequate practical operational radius limited their deployment. Tactical and technical improvements were made, not least by the crews themselves, and the S-boats would become one of the most potent weapons of the Kriegsmarine in coastal waters.27
There were extensive minefields in the North Sea and the Baltic after WWI, and thirty-eight minesweepers were retained by the Reichsmarine to take care of them. The black-painted, coal-fired sweepers worked doggedly throughout the 1920s and became a familiar sight in the ports of northern Germany. As the minefields were gradually removed, the sweepers were used for training and for testing new equipment, keeping the navy alive. Most of them had been built before or during the war, and in the early 1930s new minesweepers were needed. Orders for the first Minensuchboote were placed in November 1935. To be exempt from treaty limitations, the Type 35 minesweepers were nominally less than 600 tons. In reality, they were well over 800 tons fully loaded. In spite of some stability problems, the M-bocks were one of the most successful designs of the Kriegsmarine. Well armed, manoeuvrable and seaworthy, they were to become dreaded adversaries in the Baltic and the Channel in the first part of the war. They were expensive and complicated to build, though, and the engines in particular needed tools and skilled personnel, which were not readily available in front-line situations.
Torpedo boat S16. At the outbreak of the war the Kriegsmarine had seventeen S-boats in commission and a further ten were under construction. S16 was assigned to 2nd S-boot Flotilla based at Heligoland. (Author’s collection)
M1 was commissioned in August 1938, and by April 1940 twenty Type 35 minesweepers were in commission. Two 10.5-cm guns made up the main armament, supplemented by one 37-mm cannon, two 20-mm cannons and ample depth-charges. In addition, they could carry about thirty mines each to lay minefields as well if necessary. Tactically, the M-bocks were intended to operate in flotillas, and most of them had additional special equipment on board, depending on their intended position or task during the sweeping operations. Cruising speed was around 18 knots. M1 and M2 had Voith-Schneider propulsion instead of regular rudders and propellers.28
In parallel, the smaller, more cost-efficient R-boats or Räumboote were also developed for work in shallow, coastal waters such as harbours and estuaries. These were 60–120 tons multi-purpose motorboats used for convoy escort, mine-laying, air-sea rescue and mine-sweeping. About one-quarter of the more than 400 R-boats built had Voith-Schneider propulsion, making them highly manoeuvrable. Armament was light, usually one or two 20- or 37-mm cannons. A far less successful type of ship was the so-called Flottenbegleiter or fleet escort vessels, of which few of the ten built (F1–F10) saw any amount of active service.29
Orders for two heavy cruisers, Admiral Hipper and Blücher, were placed in secrecy by the Kriegsmarine in October 1934. A third ship, Prinz Eugen, was ordered a year later.30 Following the design specifications, Admiral Hipper achieved a displacement of 14,247 tons standard and 18,208 fully loaded, Blücher a couple of hundred tons more. In addition to the four twin 20.3-cm turrets, 10.5-cm multi-purpose guns in six stabilised twin mountings were carried. These had a sophisticated fire-control