The class was a pair of avisos built for the German (Imperial Navy) in the early 1880s. The ships, and , were the first steel-hulled ships of any kind built by the German Navy, were among the first torpedo cruiser type warships in the world, and were the progenitors of the later light cruisers of the . They were armed with a gun and one torpedo tube as their principal armament, and were capable of a top speed in excess of . They were very successful warships, remaining in active service for more than three decades.
and served extensively in various roles; Blitz spent much of her career as a flotilla leader for torpedo boats, while served with the training squadron and the main fleet. was deployed to German East Africa in 1889 to suppress the Abushiri revolt, returning to Germany in 1890. Throughout the 1890s, the ships served with the fleet, conducting a yearly routine of exercises and training cruises. They served in a variety of additional roles during the 1890s and 1900s, including as tenders, fishery protection vessels, and training ships. They operated as dedicated tenders to the battle squadrons of the High Seas Fleet by the mid-1900s, filling that role through the start of World War I. took part in Operation Albion in the Baltic Sea in late 1917 and was later used as a training ship for U-boat crews. The ships were discarded in the early 1920s and broken up for scrap.
Design
Designed in 1879, the design specifications for the -class avisos called for a top speed of from about , though the finalized design had a top speed of a knot less. The ships marked a significant advance in naval technology for the German fleet; they were the first steel-hulled vessels, and they were the first cruiser-type vessels to abandon traditional sailing masts. Their armament—a torpedo tube and a battery of light guns—reflected the growing importance of the torpedo as a weapon, since the torpedo tube served as its primary offensive armament and the guns were necessary to defend against the increasingly powerful torpedo boats of the period.
At the time of their completion, they were among the earliest torpedo cruisers in the world. The -class avisos were the first step toward creating the modern, steel-hulled light cruiser, and their modern appearance presaged later developments. Development of the aviso type would ultimately come to fruition in the light cruisers, built a decade later. The design proved to be an effective one, as evidenced by the fact that remained in active service for thirty-five years.
General characteristics
The -class ships were long at the waterline and long overall. They had a beam of and a maximum draft of forward. The ships displaced as designed and up to at full combat load. The ships' hulls were constructed with transverse and longitudinal steel frames, and contained eleven watertight compartments. A double bottom was located beneath the ships' engine rooms.
and had a crew of 7 officers and 127 enlisted men, though this number was later revised to 6 officers and 135 sailors. When serving as torpedo boat flotilla leaders, the ships had an additional 3 officers and 16 enlisted men. The ships carried several smaller boats, including one picket boat, one yawl, and one dinghy. Later in their careers, a cutter, another yawl, and another dinghy were added.
Machinery
The ships' propulsion system consisted of two horizontal 2-cylinder double expansion engines in a single engine room. The engines drove a pair of 3-bladed screws. Steam for the engines was provided by eight coal-fired locomotive boilers. After refits in the early 1890s, the ships' boilers were replaced with newer, more efficient models; received eight transverse cylindrical boilers, while had eight cylindrical boilers installed. The ships were supplied with electrical power with a single generator that operated at 67 volts. As built, the ships were fitted with a schooner rig with a sail area of to supplement her steam engines, but this was later reduced to a rig of auxiliary sails with an area of , and the sails were removed entirely by 1900.
The propulsion system was rated at , for a top speed of . Neither ship reached this speed on trials; managed , and made . The ships carried up to of coal, which allowed them to steam for approximately at a cruising speed of . Steering was controlled with one rudder.