Editing Naval mine (section)

==== Moored contact mines ====
[[File:Mine (AWM 304925).jpg|thumb|A German contact mine [[Axis naval activity in Australian waters|laid in Australian waters]] during World War II]]

Generally, this type of mine is set to float just below the surface of the water or as deep as five meters. A steel cable connecting the mine to an anchor on the seabed prevents it from drifting away. The explosive and detonating mechanism is contained in a buoyant metal or plastic shell. The depth below the surface at which the mine floats can be set so that only deep draft vessels such as aircraft carriers, battleships or large cargo ships are at risk, saving the mine from being used on a less valuable target. In [[littoral]] waters it is important to ensure that the mine does not become visible when the sea level falls at low tide, so the cable length is adjusted to take account of tides. During WWII there were mines that could be moored in {{cvt|300|m|ft|adj=on}}-deep water.

Floating mines typically have a mass of around {{cvt|200|kg|lb}}, including {{cvt|80|kg|lb}} of explosives e.g. [[Trinitrotoluene|TNT]], [[Minol (explosive)|minol]] or [[amatol]].<ref>{{Cite web|url=http://victoriancollections.net.au/items/4f72bb6697f83e03086060cb|title=World War 2 Era Contact Sea Mine - Victorian Collections|website=victoriancollections.net.au|access-date=2019-10-26|archive-date=15 November 2023|archive-url=https://web.archive.org/web/20231115004947/https://victoriancollections.net.au/items/4f72bb6697f83e03086060cb|url-status=live}}</ref>

===== Moored contact mines with plummet =====
[[File:Legen_einer_Ankertaumine.svg|thumb|Sequence of laying a moored contact mine with a plummet]]
A special form of moored contact mines are those equipped with a plummet. When the mine is launched (1), the mine with the anchor floats first and the lead plummet sinks from it (2). In doing so, the plummet unwinds a wire, the deep line, which is used to set the depth of the mine below the water surface before it is launched (3). When the deep line has been unwound to a set length, the anchor is flooded and the mine is released from the anchor (4). The anchor begins to sink and the mooring cable unwinds until the plummet reaches the sea floor (5). Triggered by the decreasing tension on the deep line, the mooring cable is clamped. The anchor continues sinking down to the bottom of the sea, pulling the mine below the water surface to a depth equal to the length of the deep line (6). Thus, even without knowing the exact seafloor depth, an exact depth of the mine below the water surface can be set, limited only by the maximum length of the mooring cable.