In World War I, the shallow water heavy gunboat proved to be an efficient heavy fire support ship, although it could not cross the sea as conventional surface ships, but in the coastal areas with the main gun to hit the land target effect is very good, the long range and strong destructive force brought by the heavy artillery is very destructive to the land target, and can play an important role in landing operations and coastal control.
A year before the outbreak of World War I (1913), Italy was influenced by the tensions in Europe at the time and proposed a series of warship construction plans, including Francesco. The Caracciolo class battleship, which was equipped with eight 381 mm main guns, but the class of battleships was not built due to shortages of raw materials, etc., its main guns were not wasted, of which 2 were used in 1915 proposed by Alfred. Cappelini shallow water gunboat.
Even shallow water gunboat, Alfred. Cappelini's seaworthiness is probably the worst of its kind, the ship is 36 meters long, 18 meters wide, 2.4 meters draft, standard displacement of 1452 tons, it is driven by a vertical double expansion steam engine, the output power is only 265 horsepower, even in the test only reached a maximum speed of 3.76 knots, a slightly stronger headwind on the sea can only stand in place, the wave height may enter the water, long-distance movement requires additional boat traction.
The main armament of the gunboat is 2 side-by-side mounted 381 mm naval guns, the gun adopts intermittent thread locking, the barrel length is 15.2 meters, can fire armor-piercing shells, the gun fires at a 20 ° elevation angle when the shell has a range of 19800 meters, the maximum range of the gun is 27300 meters, the use of 875 kg of high explosive shells and 884 kg of armor-piercing shells.
From the appearance of the main gun is installed in a rotating turret, in fact, this is not the case, the gun installed on the ship only 15 ° left and right of the range of movement, the maximum elevation angle is only 20 °, the cylindrical structure surrounding the battle chamber is an additional protective armor, in addition to the rest of the ship has no protective armor, the hull is protected by two anti-torpedo nets.
The ship entered service in April 1917 with a standard crew of probably 73 men, when the Air Force had already posed a great threat to ground and water forces, hence Alfred. The Cappelini also had 2 76 mm guns used for air defense (4 76 mm guns in some articles), which also served as secondary guns.
Alfred. After serving in service, Cappelini participated in the Battle of the Isonzo River in August (the general name for a series of battles that broke out in the Isonzo River area in 1915), which belonged in chronological terms to the eleventh Battle of Issunzo, which, together with other friendly shallow-water gunboats, bombed the Austrian positions, when the gunboats were anchored closer to the coast, and the sailors made simple camouflage of the gunboats with branches, the battle did not play much effect and had little impact on the outcome of the battle.
In November of the same year, Alfred. Accompanied by 2 cruisers and 4 destroyers, the Capellini went to Ancona to strengthen the local defenses, and just as it was approaching its destination, it encountered bad weather, the ships began to flood in large quantities, and the captain ordered at the last moment to abandon the ship and escape, because it occurred at night, the rescue work could not be carried out smoothly, by dawn 72 crew members had frozen to death 68 people, and the gunboat sank at a depth of 13 to 16 meters about 2 kilometers from the coast. Italy's several unsuccessful attempts to salvage the gunboat have ended in failure, and another salvage was made in 2007, and the waters on which the ship is located have now become an area for diving enthusiasts to explore.