The FL-boat was a weapon used by the Imperial German Navy

Kaiserliche Marine

The Imperial German Navy was the German Navy created at the time of the formation of the German Empire. It existed between 1871 and 1919, growing out of the small Prussian Navy and Norddeutsche Bundesmarine, which primarily had the mission of coastal defense. Kaiser Wilhelm II greatly expanded...

 during World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

. It was a remote-controlled motorboat, 17 m long, carrying 700 kg of explosives, which was intended to be steered directly at its targets - initially the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 monitors

Monitor (warship)

A monitor was a class of relatively small warship which was neither fast nor strongly armoured but carried disproportionately large guns. They were used by some navies from the 1860s until the end of World War II, and saw their final use by the United States Navy during the Vietnam War.The monitors...

 operating off the coast of Flanders

Flanders

Flanders is the community of the Flemings but also one of the institutions in Belgium, and a geographical region located in parts of present-day Belgium, France and the Netherlands. "Flanders" can also refer to the northern part of Belgium that contains Brussels, Bruges, Ghent and Antwerp...

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FL-boats were driven by internal combustion engines, and controlled remotely from a shore station through several miles of wire wound on a spool on the boat. An aircraft was used to signal directions to the shore station. They could attain speeds of 30 knot

Knot

A knot is a method of fastening or securing linear material such as rope by tying or interweaving. It may consist of a length of one or several segments of rope, string, webbing, twine, strap, or even chain interwoven such that the line can bind to itself or to some other object—the "load"...

s. They were constructed by Siemens-Schuckertwerke

Siemens-Schuckert

Siemens-Schuckert was a German electrical engineering company headquartered in Berlin, Erlangen and Nuremberg that was incorporated into the Siemens AG in 1966....

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On 1 March 1917 an FL-boat hit the Nieuwpoort

Nieuwpoort, Belgium

Nieuwpoort is a municipality located in Flanders, one of the three regions of Belgium, and in the Flemish province of West Flanders. The municipality comprises the city of Nieuwpoort proper and the towns of Ramskapelle and Sint-Joris. On January 1, 2008 Nieuwpoort had a total population of 11,062....

 mole

Mole (architecture)

A mole is a massive structure, usually of stone, used as a pier, breakwater, or a causeway between places separated by water. The word comes from Middle French mole and ultimately Latin mōlēs meaning a large mass, especially of rock and has the same root as molecule.Historically, the term "mole"...

 and on 28 October 1917 one hit the Royal Navy monitor HMS Erebus

HMS Erebus (I02)

HMS Erebus was a World War I monitor launched on 19 June 1916 and served in both world wars. She and her sister HMS Terror are known as the Erebus class...

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