The Drzewiecki drop collar was an external torpedo launching system most commonly used by the

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

and Imperial Russian Navies in the first two decades of the 20th century. It was designed by

Stefan Drzewiecki Stefan Drzewiecki (russian: Джеве́цкий Степа́н Ка́рлович (Казими́рович); 26 July 1844, Kunka, Podolia, Russian Empire (today Ukraine) – 23 April 1938, Paris) was a Polish scientist, journalist, engineer, co ...

, a Polish engineer and inventor. He designed and built the first

submarine A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...

in the world with electric battery-powered propulsion (1881). Generally, the drop collar consisted of a metal framework that enclosed the torpedo that could be rotated to position it clear of the

hull Hull may refer to: Structures * Chassis, of an armored fighting vehicle * Fuselage, of an aircraft * Hull (botany), the outer covering of seeds * Hull (watercraft), the body or frame of a ship * Submarine hull Mathematics * Affine hull, in affi ...

preparatory to firing. More elaborate systems were equipped with an arm that could move the drop collar to the desired firing angle. The French deployed a twin system on the aft deck of the that could be rotated from 20° to 170° from the centerline on each side of the ship.

Sources

* *{{cite journal, last1=Smigielski , first1=Adam, title=Question 27/50: Drzwiecki Submarine Torpedo Drop Collars , journal=Warship International , date=2015 , volume=LII , issue=3 , pages=222–223 , issn=0043-0374 Torpedoes