The class of protected cruisers was the last class of ships of that type built for the German Imperial Navy. The class design introduced the combined clipper and ram bow and the blocky sides that typified later German armored cruisers. The class comprised five vessels, , the lead ship, , , , and . The ships were laid down in 1895–1896, and were launched in 1897–1898 and commissioned into the fleet over the following year.
The first three ships were long and displaced at combat load; and were a slightly modified design. They were long and displaced at full load. All five ships were armed with a main battery of two guns and eight guns. The first three ships had a top speed of ; the last two were slightly slower, at . Problems with the Niclausse boilers installed on prompted the Navy to standardize boiler types in future warships.
The ships of the class served in various units in the German fleet, including on the America Station, in the East Asia Squadron, and with the home fleet. and participated in the suppression of the Boxer Uprising in China in 1900, and was involved in the Venezuela Crisis of 1902–1903. All five ships were modernized between 1905 and 1911, after which they served as training ships for naval cadets. They were mobilized into V Scouting Group at the outbreak of World War I in August 1914, but were quickly withdrawn from front-line service. They served in various secondary roles for the rest of the war. After the end of the conflict, was converted into a merchant ship, but was broken up in 1923. The other four ships were scrapped in 1920–1921.
Background In the mid-1880s, the German (Imperial Navy) had begun a program of construction to modernize its cruiser force, beginning with the of protected cruisers of 1886, followed the unprotected cruisers in 1886–1887 and in 1888. By the end of 1888, Admirals Alexander von Monts and Friedrich von Hollmann had become the chiefs of the (Imperial Admiralty) and (RMA—Imperial Naval Office), respectively. At the time, naval construction in Germany was marred by a sense of strategic confusion; the navy was at the same time building the four s—necessary for an offensive strategy—and the coastal defense ships of the and es—which belied an inherently defensive orientation for the fleet. At the same time, many elements of the naval command espoused the commerce raiding strategy of the French (Young School).
Hollmann submitted a memorandum to the (Imperial Diet) to request funding for a new construction program. He called for a total of seven new cruisers over the following three years to replace the old screw corvettes that still made up the bulk of the cruiser force, arguing that the old screw corvettes were no longer suitable as warships, owing to the proliferation of modern unprotected and protected cruisers in even minor navies around the world, along with the advances in marine steam engines, which propelled merchant vessels to speeds at which the corvettes could not catch them. The 's budget board decried what it viewed as the limitless demands of the navy. Instead of the three ships Hollmann had requested for the 1890/1891 fiscal year, the authorized just two, which were given the provisional designations "J" and "K". The former became the unprotected cruiser , but a minor scandal in 1891 over "K"—the navy had not finalized the design for the new ship by the time it had asked for the second installment of funds for her construction—angered the , which revoked funding for the new ship.
Attempts to secure the return of funds for "K" continued over the next three years, and included efforts in 1892 by (Chancellor) Leo von Caprivi to convince the parliament to authorize construction. The navy tried yet again for the 1893 fiscal year, but the Imperial German Army had significantly increased its own budget that year, which left no additional funding for the fleet. In fiscal year 1894, the navy made no attempt to secure funding for "K". By this time, the strategic confusion that marked the 1880s had come to a head; Alfred von Tirpitz had recently become the chief of staff at the (Imperial Naval High Command), and he was finalizing his famous memorandum, , which laid out his plans for the future development of the navy. Tirpitz's projections were at odds with the leadership in the RMA; he sought a combination of 1st- and 3rd-class cruisers with the sole purpose of strengthening the fleet in home waters, while the RMA still favored a mix of 1st-, 2nd-, and 4th-class cruisers optimized for commerce raiding. To make matters worse, RMA was responsible for designing new warships, but they had no input on strategic objectives or war plans, which were the high command's remit.
Design
As the RMA began work on another proposal for "K" in early 1894, Kaiser Wilhelm II interjected himself into the discussions, submitting his own proposal for a 2nd-class cruiser that was clearly inspired by contemporary French cruisers in June. The RMA decided that the new cruiser would be, at a minimum, the same size as , with roughly the same price. Wilhelm continued to submit his ideas for consideration, including two different 3rd-class cruisers. One of these vessels, submitted in October, incorporated lessons from the First Sino-Japanese War, then being fought between Japan and China. The Battle of the Yellow River appeared to show the superiority of protected cruisers armed with large quick-firing guns over larger ironclad battleships armed with larger but slower-firing guns. As a result, Wilhelm included two quick-firing guns into his proposal in October.
Hollmann drew up a list of requirements for "K" in November, including fully enclosed and armored gun turrets for the 21 cm guns, a secondary battery of guns, but other critical components were left undecided. The question remained open as to whether to retain the traditional two-shaft propulsion system or repeat the three-shaft arrangement pioneered with . Wilhelm approved the parameters that month, and the Chief Constructor, Alfred Dietrich, prepared a more detailed proposal in line with them, which the Kaiser approved on 31 December. Discussions in February and March 1895 examined the open questions, but only some were settled, including a preference for water-tube boilers (though the specific manufacturer remained in question) and the anti-torpedo boat armament. The latter centered on two choices: a uniform battery of guns or a mixed battery of guns and Maxim guns; the greater power of the 8.8 cm gun was deemed to outweigh the advantage of a uniform battery, so that option was selected.
After failing to secure budgetary approval for the new ships from the in 1892, 1893, and 1894, the finally authorized construction of three ships for the 1895–1896 budget year. The RMA's proposal was chosen and three 6,000-ton cruisers were begun in 1895. Two more vessels were authorized for 1896–1897. The believed the orders for these ships indicated that the navy's preferences for larger, more expensive battleships had shifted toward cheaper cruisers, and thus voted unanimously for the measures. By this time, the design staff had settled on the triple-shaft arrangement for the ships' engines, and decided to order boilers from three different firms, with five differing configurations across the ships, to gather experience for future vessels.
Compared to , had a displacement that was about six percent less, though she carried a much heavier armament. She also had a lower length to beam ratio, which reduced hydrodynamic efficiency, and thus maximum speed. The resulting design were smaller scale versions of the contemporary s; they featured the same fore military mast and pole mainmast and a combination of gun turrets and casemates for the secondary battery. Dietrich modeled the ship's profile, particularly the bow shape, on the contemporary United States cruiser . The ships' design set a precedent for later armored cruisers, with large, bulky sides and a combined clipper bow and ram.
The new cruisers proved to be unsatisfactory as fleet cruisers, because they were too slow and they lacked sufficient armor protection. They nevertheless provided good service as overseas cruisers and later as training ships. Because of their shortcomings, particularly compared to later vessels, the -class ships have been frequently criticized, including a characterization of them as "3-minute ships" (indicating the length of time they would survive in battle). The historian Dirk Nottelmann disagrees, pointing to contemporary vessels that had even lighter protection. He also notes the combat experiences of other fleets' protected cruisers in the First Sino-Japanese War, the Spanish–American War, and the Russo-Japanese War. Regardless, the class (along with the contemporaneous armored cruiser ) marked the beginning of a trend of German cruiser construction that lasted through the s built a decade later.
General characteristics
The first three ships of the class—, , and —were long at the waterline and long overall. They had a beam of and a draft of forward and . These ships displaced as designed and at full load. and had slightly different dimensions; they were long at the waterline and overall. Their beam was and drew forward and aft. Their displacement was also higher than the first three ships, at as designed and at combat load.
The ships' hulls were constructed with longitudinal and transverse steel frames. For the latter pair of ships, and , a single layer of wood planks were used for the hull. A layer of Muntz metal sheathing extended up to above the waterline to protect against fouling of the hull. The first three ships, , , and , did not receive sheathing as a weight reduction measure. The hull was divided into twelve watertight compartments, which were later reduced to eleven, with the exception of . The hull also incorporated a double bottom that extended for 60 percent of the length of the hull.
The ships' standard crew was 31 officers and 446 enlisted men, with an additional 9 officers and 41 enlisted while serving as a second command flagship. After their reconstruction into training ships, the crew was substantially enlarged to incorporate the trainees, with 26 officers and 658 sailors, 75 of whom were naval cadets and 300 others were cabin boys. The ships carried a number of smaller boats, including three picket boats, one launch, one pinnace, two cutters, two yawls, and three dinghies. After their modernization, the boats were significantly revised; the number of picket boats was reduced to one, a barge and a launch were added, the dinghies were removed, and five more cutters were added.
The ships were good sea boats; they had an easy motion and were dry as a result of their high forecastles. They had a tendency to pitch when steaming downwind, however, and made severe leeway in heavy winds because of their large superstructures. They were difficult to maneuver without the center shaft engaged. Steering was controlled with a single rudder. They lost only around ten percent speed in a head sea or with the rudder hard over. In addition, as the lower coal bunkers were emptied, the ships became increasingly unstable; with empty bunkers, the ships could heel over as much as fifteen degrees in a hard turn. The modernization of the ships between 1905 and 1911 rectified this problem. They had a transverse metacentric height of . As built, the ships were very hot, and ventilation had to be improved before they were commissioned.
Machinery