The Pattern 913 Swimming Crane is the first of the Harbour Helpers Line of Silverport Dockyards Limited.
As the name suggests, it is a swimming crane, capable of lifting up to 150 tons on the heavier of both arms. Capable of going to the thing they need to lift instead of the other way around, these relatively wide ships have a lot of applications in everyday operations of a harbour, especially in naval arsenals (not many things can reload VLS-cells as fast as a swimming crane) and in freighter ports, where larger, stationary cranes are scarce or need support by an additional workforce, for example to speed things up. Also, naval construction works, like dykes, would profit from having a swimming crane for the ease of heavier works.
For easier navigation in even the tightest fits, the Pattern 913 Swimming Crane is equipped with three propellers, one in the front, two aft, which are, as the crane, powered by the three onboard diesel generators with a total power of 2,500 kW. The cranes can lift, in case of the smaller one, 15 tons of equipment, in case of the larger one 150 tons 42 metres into the air over a distance of 17 metres with pinpoint accuracy.
A small crew of nine people, plus three additional people as guests, can be housed on board the Pattern 913 Swimming Crane, with enough provisions for ten days of operation.
Since the dawn of merchant shipping, there was always one question: "How do I get my stuff in big loads as fast as possible off my boat?" As warships grew in weight and their armament with them, this question became a matter of literal life and death.
Large, stationary cranes and similar infrastructure can only do so much in little time, so, in order to speed up things, several harbour authorities of the Free Lands and the SDF-Navy (more interested in a cheap, reliable and fast way to reload VLS-cells without much infrastructure) asked leading shipbuilders of the Free Lands about the possible construction of a swimming crane.
Silverport Dockyards was happy to oblige and developed the Pattern 913 Swimming Crane, which was introduced into service in 2011. It is, by no means, a high-tech sophisticated and expensive swimming crane, it simply does, what it is supposed to be doing: Lifting things up and putting them down again.