Anchor towers
Anchor mines are a subgroup of sea mines . They act against ships and submarines with an explosive charge held under the surface of the water by their anchor rope .
description
Anchor towers are simple weapons that are essentially mechanic. They consist of a mine cart or anchor , which sinks to the seabed, and the mine vessel, which is attached to the mine cart with a wire rope, the so-called anchor rope, and which floats just below the surface of the sea due to its buoyancy. Anchor mines are usually equipped with touch fuses and are triggered by contact with a ship's hull. At greater depths, anchor mines are also used against submarines.
The correct depth setting is important for anchor mines. If the mine is too deep, ships can pass it undamaged. If, on the other hand, it is too flat, there is a risk that the mine vessel is visible on the surface and thus reveals the lock. With the first mine barriers, the exact water depth had to be plumbed before laying and then the corresponding anchor rope length had to be set. This lengthy method was suitable for blocking in one's own waters, but not for blocking enemy ports.
In order not to jeopardize the safety of general shipping beyond what is militarily necessary, according to the 8th Hague Agreement , anchor towers must be disarmed if they tear themselves out of their anchorage. In practice, this is solved with a set of springs that is kept in balance by the anchor rope. If the connection to the mine car loosens, the tension on the anchor rope eases and the spring package defuses the mine. However, this mechanism can be blocked by corrosion or heavy growth, so that especially older, demolished anchor towers can pose a serious risk.
Anchor rope with lead anchor
In addition to the pre-setting of the anchor rope length, the lead weight or lead anchor has proven itself in practice. Here, as shown in the throwing diagram, the mine is ejected (1). The mine with the mine car initially floats and the lead anchor sinks into the depths (2). The lead anchor unwinds a wire, the depth line, which is used to set the depth of the mine under the water surface before it is released (3). If the set length has been unwound, the mine car is flooded and the mine is released from the mine car (4). The mine car begins to sink and the anchor rope unwinds until the lead anchor reaches the seabed (5). The anchor rope is clamped tight as the tension on the deep line decreases. The mine car sinks by the length of the deep line until it reaches the sea floor, pulling the mine by that same length below the surface of the water (6). In this way, an exact depth of the mine can be set under the water surface without knowing the exact depth. Limited only by the maximum length of the anchor rope.
Special mines
Special mines have been developed for special tasks, for example for use in great water depths or against submarines. Anchor mine mines with remote ignition have been developed, which are laid in great water depths and whose mine vessels float at similar depths to which ground mines are otherwise laid. This makes it possible to mine very deep waters.
The special mines also include those that can be switched on and off or even ignited from land. Such mines are used to protect own port entrances and waterways.
history
The anchor mine is the oldest type of mine used in large numbers. The first were deployed in front of the Hudson and Richmond forts as early as 1813. The mine barriers of the First World War consisted exclusively of anchor mines , those of the Second World War predominantly, and anchor mines were also planned or used in the Cold War and in regional conflicts after 1945.
In the Russo-Japanese War , mines were used that anchored themselves to a depth set before throwing. Initially, two different systems for automatic depth adjustment were used. When setting by water pressure, the mine vessel with the anchor sinks to the bottom. The vessel then detaches from the anchor and rises until the ambient pressure has decreased to such an extent that a spring device clamps the anchor rope. This system was used by the Imperial Navy until 1918. A double anchor rope was required, which resulted in the mine undercut in the current due to the increased water resistance and the mine being up to several meters too deep. With the lead anchor, the required depth is set using the lead . After throwing the mine vessel remains on the surface for the time being, while the anchor with the lead weight sinks. When the lead weight, which sinks faster than the anchor, reaches the bottom, a brake blocks the anchor rope and the mine vessel is pulled to the set depth. From 1916, the Royal Navy introduced the closed leading anchor, which is simpler and more reliable. During the Second World War , this was the most frequently used method of anchoring by all participating states.
Mine clearance
Mine clearing involves various methods with the help of which mines in a search area are to be rendered harmless using technical means.
To clear anchor mines, clearing harnesses are used, which are pulled through the water by minesweepers. They are either used by several boats in a group or by individual boats whose clearing cables are controlled laterally with the help of otter boards. With the help of floats, the cables are guided to a predetermined clearing depth and are supposed to grasp and cut the anchor ropes of the mines with attached grippers. The mine vessels then float up and are detonated with firearms.
Individual evidence
- ↑ Anchorage mines. (No longer available online.) In: www.minenjagd.de. Archived from the original on June 25, 2016 ; accessed on January 4, 2017 .
- ↑ Searching for mines explained easily. In: www.7tes-msg.de. Retrieved January 4, 2017 .