Editing Shaped charge (section)

==Munroe effect==
The Munroe or Neumann effect is the focusing of blast energy by a hollow or void cut on a surface of an explosive. The earliest mention of hollow charges were mentioned in 1792. [[Franz Xaver von Baader]] (1765–1841) was a German mining engineer at that time; in a mining journal, he advocated a conical space at the forward end of a blasting charge to increase the explosive's effect and thereby save powder.<ref>Franz Baader (March 1792) [https://www.digitale-sammlungen.de/de/view/bsb10704955?page=275 "Versuch einer Theorie der Sprengarbeit"] (Investigation of a theory of blasting), ''Bergmännisches Journal'' (Miners' Journal), vol. 1, no. 3, pp. 193–212. Reprinted in: Franz Hoffmann et al. ed.s, ''Franz von Baader's sämtliche Werke …'' [Franz von Baader's complete works …] (Leipzig (Germany): Herrmann Bethmann, 1854), Part I, vol. 7, [https://books.google.com/books?id=vS4CAAAAcAAJ&pg=PA153 pp. 153–166.]{{Dead link|date=February 2023 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> The idea was adopted, for a time, in Norway and in the mines of the [[Harz]] mountains of Germany, although the only available explosive at the time was gunpowder, which is not a [[high explosive]] and hence incapable of producing the [[shock wave]] that the shaped-charge effect requires.<ref>Donald R. Kennedy, [https://apps.dtic.mil/dtic/tr/fulltext/u2/a220095.pdf ''History of the Shaped Charge Effect: The First 100 Years''] {{Webarchive|url=https://web.archive.org/web/20190127203141/https://apps.dtic.mil/dtic/tr/fulltext/u2/a220095.pdf |date=2019-01-27 }} (Los Alamos, New Mexico: Los Alamos National Laboratory, 1990), pp. 3–5.</ref>

The first true hollow charge effect was achieved in 1883, by Max von Foerster (1845–1905),<ref>For a brief biography of [[:de:Max von Foerster|Max von Foerster]], see the German Wikipedia article on him.</ref> chief of the nitrocellulose factory of Wolff & Co. in [[Walsrode]], Germany.<ref>Kennedy (1990), pp. 5, 66.</ref><ref>See:

*Max von Foerster (1883) ''Versuche mit Komprimierter Schiessbaumwolle'' [Experiments with compressed gun cotton], (Berlin, Germany: Mittler und Sohn, 1883).
*Max von Foerster (1884) [https://books.google.com/books?id=wLpWAAAAYAAJ&pg=PA113 "Experiments with compressed gun cotton,"] ''Nostrand's Engineering Magazine'', vol. 31, pp. 113–119.</ref>

[[File:RL-83_HESH_round.jpg|thumb|upright=1.35|Sectioned [[RL-83 Blindicide]] rocket]]

By 1886, Gustav Bloem of [[Düsseldorf]], Germany, had filed {{US patent|342423}} for hemispherical cavity metal detonators to concentrate the effect of the explosion in an axial direction.<ref>{{US patent reference|inventor=Gustav Bloem|number=342423|title=Shell for detonating caps|y=1886|m=05|d=25}}</ref> The Munroe effect is named after [[Charles E. Munroe]], who discovered it in 1888. As a civilian chemist working at the U.S. [[Naval Torpedo Station]] at [[Newport, Rhode Island]], he noticed that when a block of explosive [[guncotton]] with the manufacturer's name stamped into it was detonated next to a metal plate, the lettering was cut into the plate. Conversely, if letters were raised in relief above the surface of the explosive, then the letters on the plate would also be raised above its surface.<ref>See:
*Charles E. Munroe (1888) [https://books.google.com/books?id=ukYsAQAAIAAJ&pg=RA1-PA62 "On certain phenomena produced by the detonation of gun cotton,"] ''Proceedings of the Newport'' [Rhode Island] ''Natural Historical Society'' 1883–1886, Report no. 6.
*Charles E. Munroe (1888) [https://books.google.com/books?id=hlM7AQAAIAAJ&pg=PA48 "Wave-like effects produced by the detonation of guncotton,"] ''American Journal of Science'', vol. 36, pp. 48–50.
*Charles E. Munroe (1888) [https://books.google.com/books?id=uGEAAAAAYAAJ&pg=PA563 "Modern explosives,"] ''Scribner's Magazine'', vol. 3, pp. 563–576.
*Kennedy (1990), pp. 5–6.</ref> In 1894, Munroe constructed his first crude shaped charge:<ref>C.E. Munroe (1894) Executive Document No. 20, 53rd [U.S.] Congress, 1st Session, Washington, D.C.</ref><ref>Charles E. Munroe (1900) [https://books.google.com/books?id=7W1MAAAAYAAJ&pg=PA300 "The applications of explosives,"] Appleton's ''Popular Science Monthly'', vol. 56, pp. 300–312, 444–455. A description of Munroe's first shaped-charge experiment appears on [https://books.google.com/books?id=7W1MAAAAYAAJ&pg=PA453 p. 453].</ref>

<blockquote>Among the experiments made&nbsp;... was one upon a safe twenty-nine inches cube, with walls four inches and three quarters thick, made up of plates of iron and steel&nbsp;... When a hollow charge of dynamite nine pounds and a half in weight and untamped was detonated on it, a hole three inches in diameter was blown clear through the wall&nbsp;... The hollow cartridge was made by tying the sticks of dynamite around a tin can, the open mouth of the latter being placed downward.<ref>Munroe (1900), p. 453.</ref></blockquote>

Although Munroe's experiment with the shaped charge was widely publicized in 1900 in ''Popular Science Monthly'', the importance of the tin can "liner" of the hollow charge remained unrecognized for another 44&nbsp;years.<ref>Kennedy (1990), p. 6.</ref> Part of that 1900 article was reprinted in the February 1945 issue of ''[[Popular Science]]'',<ref name="popSci">[https://books.google.com/books?id=AyEDAAAAMBAJ&pg=PAA65 "It makes steel flow like mud", ''Popular Science'', February 1945, pp. 65–69]</ref> describing how shaped-charge warheads worked. It was this article that at last revealed to the general public how the United States Army ''[[bazooka]]'' actually worked against armored vehicles during WWII.

In 1910, Egon Neumann of Germany discovered that a block of [[trinitrotoluene|TNT]], which would normally dent a steel plate, punched a hole through it if the explosive had a conical indentation.<ref>{{cite book |title= The Big Bang: A history of explosives |author= G. I. Brown |isbn= 0-7509-1878-0 |publisher= Sutton Publishing Limited |year= 1998 |location= Stroud, Gloucestershire |page= [https://archive.org/details/bigbanghistoryof00brow/page/166 166] |url-access= registration |url= https://archive.org/details/bigbanghistoryof00brow/page/166}}</ref><ref>{{cite book |title= Fundamentals of Shaped Charges |author1=W. P. Walters |author2=J. A. Zukas |isbn= 0-471-62172-2 |publisher= John Wiley & Sons inc. |year= 1989 |location= New York |pages= 12–13}}</ref> The military usefulness of Munroe's and Neumann's work was unappreciated for a long time. Between the world wars, academics in several countries{{snd}} Myron Yakovlevich Sukharevskii (Мирон Яковлевич Сухаревский) in the Soviet Union,<ref>М. Сухаревский [M. Sukharevskii] (1925) ''Техника и Снабжение Красной Армии'' (Technology and Equipment of the Red Army), no. 170, pp. 13–18; (1926) ''Война и Техника'' (War and Technology), no. 253, pp. 18–24.</ref> William H. Payment and Donald Whitley Woodhead in Britain,<ref>{{cite journal |author1=William Payman |author2=Donald Whitley Woodhead |author3=Harold Titman |name-list-style=amp |date= February 15, 1935 |title= Explosion waves and shock waves, Part II — The shock waves and explosion products sent out by blasting detonators |journal= Proceedings of the Royal Society of London |volume= 148 |issue= 865 |pages= 604–622 |doi=10.1098/rspa.1935.0036|bibcode=1935RSPSA.148..604P |doi-access= free}} See also: {{cite journal |author1=W. Payman |author2=D. W. Woodhead |name-list-style=amp |date= December 22, 1937 |title= Explosion waves and shock waves, V — The shock wave and explosion products from detonating high explosives |journal= Proceedings of the Royal Society of London A |volume= 163 |issue= 915 |pages= 575–592 |doi=10.1098/rspa.1937.0246|doi-access= free}}</ref> and [[Robert W. Wood|Robert Williams Wood]] in the U.S.<ref>{{cite journal |author= R. W. Wood |date= November 2, 1936 |title= Optical and physical effects of high explosives |journal= Proceedings of the Royal Society of London |volume= 157A |issue= 891 |pages= 249–261|doi= 10.1098/rspa.1936.0191 |bibcode= 1936RSPSA.157..249W|doi-access= free }}</ref>{{snd}} recognized that projectiles could form during explosions. 

In 1932 Franz Rudolf Thomanek, a student of physics at Vienna's ''Technische Hochschule'', conceived an anti-tank round that was based on the hollow charge effect. When the Austrian government showed no interest in pursuing the idea, Thomanek moved to [[Technical University of Berlin|Berlin's ''Technische Hochschule'']], where he continued his studies under the ballistics expert Carl Julius Cranz.<ref>For a biography of Carl Julius Cranz (1858–1945), see:
*{{cite book |author= Peter O. K. Krehl |title= History of Shock Waves, Explosions and Impact: A Chronological and Biographical Reference |publisher= Springer-Verlag |year= 2009 |location= Berlin, Germany |pages= 1062–1063 |isbn= 9783540304210 |url= https://books.google.com/books?id=PmuqCHDC3pwC&pg=PA1062}}
*[[:de:Carl Cranz|German Wikipedia: Carl Cranz]]</ref> There in 1935, he and Hellmuth von Huttern developed a prototype anti-tank round. Although the weapon's performance proved disappointing, Thomanek continued his developmental work, collaborating with [[Hubert Schardin]] at the ''Waffeninstitut der Luftwaffe'' (Air Force Weapons Institute) in Braunschweig.<ref>Helmut W. Malnig (2006) "Professor Thomanek und die Entwicklung der Präzisions-Hohlladung" (Professor Thomanek and the development of the precision hollow charge), ''Truppendienst'', no. 289. Available on-line at: [http://www.bundesheer.at/truppendienst/ausgaben/artikel.php?id=402 ''Bundesheer'' (Federal Army (of Austria))] {{Webarchive|url=https://web.archive.org/web/20150226102757/http://www.bundesheer.at/truppendienst/ausgaben/artikel.php?id=402 |date=2015-02-26 }}</ref>

By 1937, Schardin believed that hollow-charge effects were due to the interactions of shock waves. It was during the testing of this idea that, on February 4, 1938, Thomanek conceived the shaped-charge explosive (or ''Hohlladungs-Auskleidungseffekt'' (hollow-charge liner effect)).<ref>Kennedy (1990), p. 9.</ref> (It was Gustav Adolf Thomer who in 1938 first visualized, by flash radiography, the metallic jet produced by a shaped-charge explosion.<ref>See:
*Kennedy (1990), p. 63.
*Krehl (2009), p. 513.</ref>) Meanwhile, [[Henry Mohaupt|Henry Hans Mohaupt]], a chemical engineer in Switzerland, had independently developed a shaped-charge munition in 1935, which was demonstrated to the Swiss, French, British, and U.S. militaries.<ref>See:
*H. Mohaupt, "Chapter 11: Shaped charges and warheads", in: F. B. Pollad and J. A. Arnold, ed.s, ''Aerospace Ordnance Handbook'' (Englewood Cliffs, New Jersey: Prentice-Hall, 1966).
*Kennedy (1990), pp. 10–11.
*William P. Walters (September 1990) "The Shaped Charge Concept. Part 2. The History of Shaped Charges", Technical Report BRL-TR-3158, U.S. Army Laboratory Command, Ballistic Research Laboratory (Aberdeen Proving Ground, Maryland), p. 7. Available on-line at: [https://apps.dtic.mil/dtic/tr/fulltext/u2/a226772.pdf Defense Technical Information Center] {{Webarchive|url=https://web.archive.org/web/20190401204621/https://apps.dtic.mil/dtic/tr/fulltext/u2/a226772.pdf |date=2019-04-01 }}</ref>

During World War II, shaped-charge munitions were developed by Germany ([[Panzerschreck]], [[Panzerfaust]], [[Panzerwurfmine]], [[Mistel]]), Britain ([[No. 68 AT grenade]], [[PIAT]], Beehive cratering charge), the Soviet Union ([[RPG-43]], [[RPG-6]]), the U.S. ([[M9 rifle grenade]], [[bazooka]]),<ref>Donald R. Kennedy, "[https://apps.dtic.mil/dtic/tr/fulltext/u2/a220095.pdf History of the Shaped Charge Effect: The First 100 Years] {{Webarchive|url=https://web.archive.org/web/20190127203141/https://apps.dtic.mil/dtic/tr/fulltext/u2/a220095.pdf |date=2019-01-27 }}", D.R. Kennedy and Associates, Inc., Mountain View, California, 1983</ref><ref>{{cite book |last1=Tucker-Jones |first1=Anthony |title=Hitler's Panzers: The Complete History 1933–1945 |date=5 February 2020 |publisher=Pen and Sword Military |isbn=978-1-5267-4161-5 |page=29 |url=https://books.google.com/books?id=i17BEAAAQBAJ |language=en}}</ref> and Italy (''Effetto Pronto Speciale'' shells for various artillery pieces).<ref>{{cite book |last1=Andrews |first1=William |title=Tank Gun Systems: The First Thirty Years, 1916–1945: A Technical Examination |date=30 June 2023 |publisher=Pen and Sword Military |isbn=978-1-3990-4237-6 |pages=20–12−21–1 |url=https://books.google.com/books?id=HdS4EAAAQBAJ |language=en}}</ref> The development of shaped charges revolutionized [[anti-tank warfare]]. Tanks faced a serious vulnerability from a weapon that could be carried by an [[infantry]]man or aircraft.

One of the earliest uses of shaped charges was by German glider-borne troops against the Belgian [[Battle of Fort Eben-Emael|Fort Eben-Emael]] in 1940.<ref>{{cite book |author= Col. James E. Mrazek (Ret.) |title= The Fall of Eben Emael |publisher= Luce |date= 1970 |asin= B000IFGOVG}}</ref> These demolition charges – developed by Dr. Wuelfken of the German Ordnance Office – were ''unlined'' explosive charges<ref name=thomanek61>{{cite journal|last1=Thomanek|first1=Rudolf|title=The Development of Lined Hollow Charge|journal=Explosivstoffe|date=1960|volume=8|issue=8|url=https://apps.dtic.mil/dtic/tr/fulltext/u2/255668.pdf|archive-url=https://web.archive.org/web/20190127202930/https://apps.dtic.mil/dtic/tr/fulltext/u2/255668.pdf|url-status=dead|archive-date=January 27, 2019|access-date=28 April 2015}}</ref> and did not produce a metal jet like the modern HEAT warheads.
Due to the lack of metal liner they shook the turrets but they did not destroy them, and other airborne troops were forced to climb on the turrets and smash the gun barrels.<ref name=lucas>{{cite book|last1=Lucas|first1=James|title=Storming eagles: German airborne forces in World War Two|date=1988|publisher=Arms and Armour|location=London|isbn=9780853688792|page=23}}</ref>