Editing Voith Schneider Propeller (section)

==History==
The Voith Schneider propeller was originally a design for a [[hydro-electric]] [[turbine]].<ref>{{cite book |last=Goldsworthy |first=E. C. |title=The Voith Schneider Propellor |url=https://www.cdvandt.org/BIOS-28-item-6.pdf |date=1945 |series=British Intelligence Oversight Subcommittee (BIOS), Report no. 28 |place=London |publisher=HM Stationery Office}}</ref> Its Austrian inventor, Ernst Schneider, had a chance meeting on a train with a manager at Voith's subsidiary [[St. Pölten]] works; this led to the turbine being investigated by Voith's engineers, who discovered that although it was no more efficient than other water turbines, Schneider's design worked well as a pump by reversing the flow through the device. By changing the orientation of the vertical blades, it could be made to function as a combined [[propeller]] and [[rudder]].

[[Image:VSPsurtug.jpg|right|thumb|upright=1.35|Twin Voith Schneider propeller with thrust plate on a tug's hull]]
In 1928 a prototype was installed in a 60-hp motor launch named ''Torqueo'' (Latin:''I spin'') and trials were carried out on [[Lake Constance]].{{sfnp|Jürgens|2002|pages=26–28}} A number of German minesweepers ([[R boats]]) were fitted with VSPs; the first of these was the R8, built in 1929 by [[Lürssen]]. By 1931 VSPs were being fitted in new vessels on Lake Constance run by the [[Deutsche Reichsbahn|German State Railways]]. The first such ship to use the Voith Schneider propeller was the excursion boat ''Kempten''. Two German 1935-type [[M class minesweeper (Germany)|M class minesweeper]]s [[German minesweeper M-1|''M-1'']] and ''M-2'' were fitted with VSPs.

The first British ship to use Voith Schneider propellers was the double-ended Isle of Wight ferry ''[[MV Lymington]]'', launched in 1938. Some 80 ships had been installed with VSPs by the end of the 1930s, including the uncompleted 1938 German aircraft carrier ''[[German aircraft carrier Graf Zeppelin|Graf Zeppelin]]'' (two auxiliary units in the bow), and the Japanese submarine cable laying ship ''Toyo-maru'' (also 1938).

Three vessels (''John Burns'', ''Ernest Bevin'', and ''James Newman'') which were in service for the [[Woolwich Ferry]] until 2018 featured Voith-Schneider propulsion systems. They were built in 1963 by the [[Caledon Shipbuilding & Engineering Company]] of Dundee and featured one VSP in the bow and a second in the stern for remarkable maneuverability. The Tay Ferries ''Scotscraig''  which were built by the Caledon in the 1950s also used VSPs.It was essentially a replacement copy of the earlier ''Abercraig'' ferry, which was built by Fleming and Ferguson Paisley yard for Dundee Harbour crossings and launched in 1938. The "Abercraig" also featured VSPs.<ref>{{cite web |url=https://www.thecourier.co.uk/fp/nostalgia/1299094/the-last-ferry-to-make-the-tay-crossing-in-1966-went-on-to-become-a-star-in-hollywood-with-robin-williams/ |title=The last ferry to make the Tay crossing in 1966 went on to become a star in Hollywood with Robin Williams |author=Graeme Strachan |date=April 30, 2020 |website=The Courier.co.uk}}</ref>

The US Navy built twelve VSP-equipped [[Osprey-class coastal minehunter|''Osprey''-class coastal minehunter]]s in the 1990s.{{sfnp|Marriott|2001|pages=[https://archive.org/details/vitalguidetomode00marr/page/n48 95]}}  These vessels have been decommissioned, six were sold to foreign navies.{{citation needed|date=March 2014}} and six were sold for "dismantlement purposes only."<ref>{{cite web |url = http://gsaauctions.gov/gsaauctions/aucdsclnk?sl=31QSCI14049001 |title = Lot of MHCS for Dismantlement | website = GSAauctions.gov |date = 8 April 2014 |access-date = 3 March 2021}}</ref> The [[French Navy]] operates sixteen [[tugboats]] of the [[RPC12]] type, that can provide a 12-tonne [[bollard pull]] thanks to two Voith Schneider propellers.<ref>{{Cite web |title=Remorqueur type RPC 12 : Caractéristiques principales |url=http://netmarine.net/f/bat/rpc12/caracter.htm |publisher=NetMarine |language=fr}}</ref>

The same device, mounted on a horizontal rather than a vertical axis, has been used to provide lift and propulsion on a few experimental aeroplanes, known as "[[cyclogyro]]s". None of them were very successful.<ref name="self">{{Cite web |title=The Cyclogyros |url=http://www.douglas-self.com/MUSEUM/TRANSPORT/cyclogyro/cyclogyro.htm |access-date=2014-10-04 |website=The Museum of Retro Technology |publisher=Douglas Self}}</ref> It has also more recently been proposed as an alternative to rotors for drone applications.<ref name="cyclotech">{{Cite web |title=Cyclotech brings a totally unique propulsion system to the eVTOL world |url=https://newatlas.com/aircraft/cyclotech-cyclogyro-evtol-voith-schneider/ |access-date=2020-10-22 |website=New Atlas |publisher=Gizmag}}</ref>