Editing Katyusha rocket launcher (section)

== World War II ==
[[File:RIAN archive 303890 A battery of Katyusha during the 1941-1945 Great Patriotic War.jpg|thumb|A battery of Katyusha launchers fires at German forces during the [[Battle of Stalingrad]], 6 October 1942]]
[[File:Залп гвардейских минометов "Катюша" 1-го Белорусского фронта.jpg|thumb|Katyusha salvo during the [[Vistula–Oder offensive]], January 1945]]
Katyusha rocket launchers, which were built in [[Voronezh]], were mounted on many platforms during World War II, including on trucks, [[artillery tractor]]s, tanks, and [[armoured train]]s, as well as on naval and riverine vessels as assault support weapons. Soviet engineers also mounted single Katyusha rockets on lengths of [[Track (rail transport)|railway track]] to serve in urban combat.{{cn|date=January 2023}}

The design was relatively simple, consisting of racks of parallel rails on which [[rocket]]s were mounted, with a folding frame to raise the rails to launch position. Each truck had 14 to 48 launchers. The  [[RS-82|M-13]] rocket of the BM-13 system was {{convert|80|cm|ftin|abbr=on}} long, {{convert|13.2|cm|abbr=on}} in diameter and weighed {{convert|42|kg|abbr=on}}.<ref name="Bishop" />

The weapon is less accurate than conventional [[artillery]] guns, but is extremely effective in [[saturation bombardment]]. A [[artillery battery|battery]] of four BM-13 launchers could fire a salvo in 7–10 seconds that delivered 4.35 tons of high explosives over a {{convert|400000|m2|sqft|adj=on}} impact zone,<ref name=Zaloga-1984-154>Zaloga, p 154.</ref> making its power roughly equivalent to that of 72 conventional artillery guns.  With an efficient crew, the launchers could [[Shoot-and-scoot|redeploy to a new location immediately after firing]], denying the enemy the opportunity for [[counterbattery fire]]. Katyusha batteries were often massed in very large numbers to create a [[Combat stress reaction|shock effect]] on enemy forces. The weapon's disadvantage was the long time it took to reload a launcher, in contrast to conventional artillery guns which could sustain a continuous, albeit low, rate of fire.{{cn|date=January 2023}}

=== Development ===
{{main|Reactive Scientific Research Institute}}
[[File:Verkhnyaya Pyshma Tank Museum 2011 029.jpg|thumb|BM-13N Katyusha on a [[Lend-Lease]] [[Studebaker US6 2½-ton 6×6 truck|Studebaker US6 {{frac|2|1|2}}-ton 6×6 truck]], at the [[Museum of the Great Patriotic War, Moscow|UMMC Museum Complex]], [[Verkhnyaya Pyshma]]]]
[[File:BM-31-12 on ZIS-12 chassis at the Museum on Sapun Mountain Sevastopol 4.jpg|thumb|BM-31-12 on ZIS-12 at the Museum ([[Diorama]]) on Sapun Mountain, [[Sevastopol]]]]
[[File:BM-13-16 on a ZiS-151 chassis in a military museum in Belarus.jpg|thumb|Katyusha on a [[ZIS-151]] truck]]
[[File:BM 13 TBiU 7.jpg|thumb|upright|Reloading a BM-13]]
[[File:KatyushaMusee.jpg|thumb|upright=.5|An M13 rocket for the Katyusha launcher on display in [[Musée de l'Armée]].]]

Initial development of [[Solid-propellant rocket|solid propellant rockets]] was carried out by [[Nikolai Tikhomirov (chemical engineer)|Nikolai Tikhomirov]] at the Soviet [[Gas Dynamics Laboratory]] (GDL), with the first test-firing of a solid fuel rocket carried out in March 1928, which flew for about 1,300 meters<ref name="RSB_GDL">{{cite web |last1=Zak |first1=Anatoly |title=Gas Dynamics Laboratory |url=http://www.russianspaceweb.com/gdl.html |website=Russian Space Web |access-date=29 May 2022}}</ref> The rockets were used to assist [[JATO|take-off of aircraft]] and were later developed into the [[RS-82 (rocket family)|RS-82 and RS-132]] (RS for {{lang|ru-Latn|Reaktivnyy Snaryad}}, 'rocket-powered shell')<ref>{{cite book| author = АКИМОВ В.Н., КОРОТЕЕВ А.С., ГАФАРОВ А.А. и другие | chapter = Оружие победы — «Катюша»| chapter-url = https://drive.google.com/file/d/0B1hNj_0pyrU8bTJQZjVSTXVfRVU/view| url = https://elibrary.ru/item.asp?id=19633690& | title = Исследовательский центр имени М. В. Келдыша. 1933-2003 : 70 лет на передовых рубежах ракетно-космической техники |location= М |year= 2003 |publisher= Машиностроение | pages = 92–101| isbn = 5-217-03205-7| ref = Центр Келдыша}}</ref> in the early 1930s led by [[Georgy Langemak]],<ref name = 'Siddiqi'>{{cite book |last1=Siddiqi |first1=Asif |title=Challenge to Apollo : the Soviet Union and the space race, 1945-1974 |date=2000 |publisher=National Aeronautics and Space Administration, NASA History Div. |pages=9|location=Washington, D.C. |url=https://history.nasa.gov/SP-4408pt1.pdf |access-date=3 July 2022}}</ref> including firing rockets from aircraft and the ground. In June 1938, GDL's successor [[Reactive Scientific Research Institute]] (RNII) began building several [[prototype]] launchers for the modified 132&nbsp;mm M-132 rockets.<ref>{{cite web |last1=Zak |first1=Anatoly |title=History of the Rocket Research Institute, RNII |url=http://www.russianspaceweb.com/rnii.html |website=Russian Space Web |access-date=7 July 2022}}</ref> Firing over the sides of [[ZIS-5 (truck)|ZIS-5]] trucks proved unstable, and V.N. Galkovskiy proposed mounting the launch rails longitudinally. In August 1939, the result was the BM-13 (BM stands for ''боевая машина'' (translit. ''boyevaya mashina''), 'combat vehicle' for M-13 rockets).<ref name=Zaloga-1984-150 />

The first large-scale testing of the rocket launchers took place at the end of 1938, when 233 rounds of various types were used. A salvo of rockets could completely straddle a target at a range of {{convert|5,500|m|mi}}. But the artillery branch was not fond of the Katyusha, because it took up to 50 minutes to load and fire 24 rounds, while a conventional howitzer could fire 95 to 150 rounds in the same time.{{citation needed|date=August 2008}} Testing with various rockets was conducted through 1940, and the BM-13-16 with launch rails for sixteen rockets was authorized for production. Only forty launchers were built before [[Operation Barbarossa|Germany invaded the Soviet Union]] in June 1941.<ref name=Zaloga-1984-153 />

After their success in the first month of the war, mass production was ordered and the development of other models proceeded. The Katyusha was inexpensive and could be manufactured in light industrial installations which did not have the heavy equipment to build conventional artillery gun barrels.<ref name=Zaloga-1984-154 /> By the end of 1942, 3,237 Katyusha launchers of all types had been built, and by the end of the war total production reached about 10,000.<ref name=Zaloga-1984-154-55>Zaloga, pp 154–55.</ref>

The truck-mounted Katyushas were installed on [[ZIS-6]] 6×4 trucks, as well as the two-axle [[ZIS-5 (truck)|ZIS-5]] and [[ZIS-5V]]. In 1941, a small number of BM-13 launchers were mounted on [[STZ-5]] artillery tractors. A few were also tried on [[KV tank]] chassis as the KV-1K, but this was a needless waste of heavy armour. Starting in 1942, they were also mounted on various British, Canadian and U.S. [[Lend-Lease]] trucks, in which case they were sometimes referred to as BM-13S. The [[off-road|cross-country]] performance of the [[Studebaker US6 2½-ton 6×6 truck]] was so good that it became the GAU's standard mounting in 1943, designated BM-13N (''normalizovanniy'', 'standardized'), and more than 1,800 of this model were manufactured by the end of World War II.<ref>Zaloga, pp 153–54.</ref> After World War II, BM-13s were based on Soviet-built [[ZIS-151]] trucks.

The 82&nbsp;mm BM-8 was approved in August 1941, and deployed as the BM-8-36 on truck beds and BM-8-24 on [[T-40]] and [[T-60 tank|T-60]] light tank chassis. Later these were also installed on [[GAZ-67]] jeeps as the BM-8-8, and on the larger [[Studebaker]] trucks as the BM-8-48.<ref name=Zaloga-1984-154 /> In 1942, the team of scientists Leonid Shvarts, Moisei Komissarchik and engineer Yakov Shor received the [[State Stalin Prize|Stalin Prize]] for the development of the BM-8-48.<ref>Rachel Bayvel, "[http://www.jewishquarterly.org/article.asp?articleid=91 Tales of 'Tank City'. Rachel Bayvel Celebrates the Soviet Jews Who Produced Weapons for Allied Victory] {{webarchive|url=https://web.archive.org/web/20090131121742/http://www.jewishquarterly.org/article.asp?articleid=91 |date=2009-01-31 }}". ''Jewish Quarterly'' no. 198, summer 2005. Retrieved on 2008-09-30.</ref><ref>Yosif Kremenetsky (1999), "[http://www.usfamily.net/web/joseph/evr_v_prom_sssr.htm Inzhenerno-tekhnicheskaya deyatel’nost’ yevreyev v SSSR] {{webarchive|url=https://archive.today/20130222191348/http://www.usfamily.net/web/joseph/evr_v_prom_sssr.htm |date=2013-02-22 }} (Engineering-technical activities of Jews in the USSR)", ''Yevrey pri bol’shevistskom stroye (Jews in the Bolshevist order)'', Minneapolis. Retrieved on 2008-09-30.</ref>

Based on the M-13, the M-30 rocket was developed in 1942. Its bulbous warhead required it to be fired from a grounded frame, called the M-30 (single frame, four round; later double frame, 8 round), instead of a launch rail mounted on a truck. In 1944 it became the basis for the BM-31-12 truck-mounted launcher.<ref name=Zaloga-1984-154 />

A battery of BM-13-16 launchers included four firing vehicles, two reload trucks and two technical support trucks, with each firing vehicle having a crew of six. Reloading was executed in 3–4 minutes, although the standard procedure was to [[Shoot-and-scoot|switch to a new position]] some 10&nbsp;km away due to the ease with which the battery could be identified by the enemy. Three batteries were combined into a division (company), and three divisions into a separate mine-firing regiment of rocket artillery.{{cn|date=January 2023}}

=== Variants ===
Soviet World War II rocket systems were named according to set patterns:
* Ground vehicles were designated BM-''x''-''y'', where ''x'' referred to the rocket model and ''y'' the number of launch rails or tubes.
* towed trailers and sledges used the format M-''x''-''y'' 
* In navy use, the order of the elements was different, taking the form ''y''-M-''x''

For example, the BM-8-16 was a vehicle with 16 rails for M-8 rockets while the BM-31-12 fired the M-31 rockets from 12 launch tubes. Short names such as BM-8 or BM-13 were used as well. The chassis carrying the launcher was not defined in the name e.g. BM-8-24 referred to a truck mounted launcher (ZIS-5) as well as on the T-40 tank and on the STZ-3 [[artillery tractor]]. 

Chassis for the launchers included:
* Soviet-built [[ZIS-5 (truck)|ZIS-5]], [[ZIS-6]], [[Ford Model AA|GAZ-AA]] trucks, and post war the [[ZIS-151]]
* [[STZ-5]] tracked artillery tractor
* [[T-40]] tank
* Lend-lease provided [[Studebaker US6 2½-ton 6x6 truck|Studebaker US6]] truck,
* Armored train car,
* River boat,
* Towed sledge,
* Towed trailer,
* Backpack (portable variant, so called "mountain Katyusha"),


{|class="wikitable sortable"
|+Katyusha mountings<ref name=Porter-2009-158-165>Porter, pp 158–65.</ref><ref name="Bishop">{{cite book|title=The Encyclopedia of Weapons of World War II |first=Chris |last=Bishop|publisher=Sterling Publishing Company|year=2002|pages=173–174|isbn=1-58663-762-2 |orig-date =1998}}</ref><ref>{{cite book|title=Soviet military review|publisher=Krasnaya Zvezda Publishing House|year=1974|page=13}}</ref>
|-
! style="width:15%;" | Weapon
! style="width:11%;" | [[Caliber]] (mm)
! style="width:5%;"| Tubes/<br />rails
! style="width:60%;"| Chassis
|-
| align="center" | BM-8
| align="right" | 82
| align="right" | 1
| Improvised vehicle mount, towed trailer or sled

|-
| align="center" | M-8-6
| align="right" | 82
| align="right" | 6
| Towed trailer or sled
|-
| align="center" | BM-8-8
| align="right" | 82
| align="right" | 8
| [[Willys MB]] jeep
|-
| align="center" | M-8-12
| align="right" | 82
| align="right" | 12
| Towed trailer or sled
|-
| align="center" | 16-M-8
| align="right" | 82
| align="right" | 16
| [[Project 1125 armored river boat]]
|-
| align="center" | BM-8-24
| align="right" | 82
| align="right" | 24
| [[T-40 tank|T-40 light tank]], [[T-60 tank|T-60 light tank]]
|-
| align="center" | 24-M-8
| align="right" | 82
| align="right" | 24
| [[Project 1125 armored river boat]]
|-
| align="center" | BM-8-36
| align="right" | 82
| align="right" | 36
| ZIS-5 truck, ZIS-6 truck
|-
| align="center" | BM-8-40
| align="right" | 82
| align="right" | 40
| Towed trailer, GAZ-AA truck
|-
| align="center" | BM-8-48
| align="right" | 82
| align="right" | 48
| ZIS-6 truck, Studebaker US6 U3 truck, rail carriage
|-
| align="center" | BM-8-72
| align="right" | 82
| align="right" | 72
| Rail carriage
|-
| align="center" | BM-13
| align="right" | 132
| align="right" | 24
| ZIS-6 truck, improvised vehicle mount, towed trailer or sled
|-
| align="center" | 6-M-13
| align="right" | 132
| align="right" | 6
| [[Project 1125 armored river boat]]
|-
| align="center" | BM-13-16
| align="right" | 132
| align="right" | 16
| [[International K and KB series|International K7]] "Inter" truck, International M-5-5-318 truck, [[Fordson WOT8]] truck, Ford/[[Marmon-Herrington]] HH6-COE4 truck, [[Chevrolet]] G-7117 truck, Studebaker US6 U3 truck, [[GMC CCKW]]-352M-13 truck, rail carriage
|-
| align="center" | M-20-6
| align="right" | 132
| align="right" | 6
| static launching rail
|-
| align="center" | M-30-4
| align="right" | 300
| align="right" | 4
| static launching rail, in 1944 also available with 2x4 launching rails (M-30-8)
|-
| align="center" | M-31-4
| align="right" | 300
| align="right" | 4
| static launching rail, in 1944 also available with 2x4 launching rails (M-31-8)
|-
| align="center" | BM-31-12
| align="right" | 300
| align="right" | 12
| Studebaker US6 U3 truck
|}

{|class="wikitable sortable" style="font-size:98%; text-align:right;"
|+Katyusha rockets:<ref name="Bishop" />
|-
!  Weapon name
! Caliber<br /> (mm)
!  Warhead<br />kg (lb)
!  Maximum range<br />m (yd)
|-
| align="left" | M-8
| 82
| {{convert|0.64|kg|lb|abbr=values}}
| {{convert|5900|m|yd|abbr=values}}
|-
| align="left" | M-13
| 132
| {{convert|4.9|kg|lb|abbr=values}}
| {{convert|8740|m|yd|abbr=values}}
|-
| align="left" | M-13DD
| 132
| {{convert|4.9|kg|lb|abbr=values}}
| {{convert|11,800|m|yd|abbr=values}}
|-
| align="left" | M-13UK
| 132
| {{convert|4.9|kg|lb|abbr=values}}
| {{convert|7900|m|yd|abbr=values}}
|-
| align="left" | M-20
| 132
| {{convert|18.4|kg|lb|abbr=values}}
| {{convert|5050|m|yd|abbr=values}}
|-
| align="left" | M-30
| 300
| {{convert|28.9|kg|lb|abbr=values}}
| {{convert|2800|m|yd|abbr=values}}
|-
| align="left" | M-31
| 300
| {{convert|28.9|kg|lb|abbr=values}}
| {{convert|4325|m|yd|abbr=values}}
|-
| align="left" | M-31UK
| 300
| {{convert|28.9|kg|lb|abbr=values}}
| {{convert|4000|m|yd|abbr=values}}
|}

The M-8 and M-13 rocket could also be fitted with smoke warheads, although this was not common.

[[File:Bundesarchiv_Bild_101I-300-1863-18,_Riva-Bella, Vorführung Panzerwerfer.jpg|thumb|The German ''8 cm Raketen-Vielfachwerfer'' was based on the Katyusha]]

==== Foreign variants ====

The [[Axis powers]] had captured Katyushas during the war. Germany considered producing a local copy, but instead created the ''[[8 cm Raketen-Vielfachwerfer]]'', which was based on the Katyusha.<ref>{{Cite book|url=https://archive.org/details/mortarsrockets0000cham/page/35|title=Mortars and rockets|last=Chamberlain|first=Peter|date=1975|page=[https://archive.org/details/mortarsrockets0000cham/page/35 35]|publisher=Arco Pub. Co|others=Gander, Terry|isbn=0668038179|location=New York|oclc=2067459}}</ref>

Romania had started developing its [[Mareșal (tank destroyer)|Mareșal tank destroyer]] in late 1942. One of the first experimental models was equipped with a Katyusha rocket launcher and tested in the summer of 1943. The project was not continued.{{sfn|Scafeș|2004|p=213}}

=== Combat history ===

The multiple rocket launchers were top secret at the beginning of World War II and a special unit of [[Internal troops|NKVD troops]] was raised to operate them.<ref name=Zaloga-1984-154 /> On July 14, 1941, an experimental artillery battery of seven launchers was first used in battle at [[Rudnya, Rudnyansky District, Smolensk Oblast|Rudnya]], [[Smolensk Oblast]] under the command of Captain [[Ivan Flyorov]], destroying a concentration of German troops with tanks, armored vehicles and trucks in the marketplace, causing massive [[German Army (1935–1945)|German Army]] casualties and panicked retreat from the town.<ref>"История Великой Отечественной войны" в 6 томах (History of Great Patriotic War), vol. 2, p. 66, chapter by field-marshal Andrey Eremenko</ref><ref>Andrey Sapronov «Россия» newspaper No. 23 of June 21–27, 2001</ref><ref>Andrey Sapronov «Парламентская газета» No 80 of May 5, 2005</ref>  This was the first time the Katyusha was ever used in combat. <ref>{{Cite book |last=Zhukov |first=Georgy |title=Marshal of Victory: The Autobiography of General Georgy Zhukov |date=2013 |isbn=978-1-78159-291-5 |pages=495|publisher=Pen & Sword Military }}</ref> Following the success, the [[Red Army]] organized new [[Guards unit (Soviet Union)|Guards]] mortar batteries for the support of infantry divisions. A battery's complement was standardized at four launchers. They remained under NKVD control until German ''[[Nebelwerfer]]'' rocket launchers became common later in the war.<ref name=Zaloga-1984-154-55 />

On August 8, 1941, Stalin ordered the formation of eight special Guards mortar [[regiment]]s under the direct control of the [[Reserve of the Supreme High Command]] (RVGK).  Each regiment comprised three [[battalion]]s of three batteries, totalling 36 BM-13 or BM-8 launchers.  Independent Guards mortar battalions were also formed of 12 launchers in three batteries of four.  By the end of 1941, there were eight regiments, 35 independent battalions, and two independent batteries in service, a total of 554 launchers.<ref name=Zaloga-1984-155>Zaloga, p 155.</ref>

In June 1942 heavy Guards mortar battalions were formed around the new M-30 static rocket launch frames, consisting of 96 launchers in three batteries. In July, a battalion of BM-13s was added to the establishment of a tank corps.<ref>Zaloga, p 147.</ref> In 1944, the BM-31 was used in motorized heavy Guards mortar battalions of 48 launchers. In 1943, Guards mortar brigades, and later divisions, were formed equipped with static launchers.<ref name=Zaloga-1984-155 />

At dawn on September 5, the preparatory artillery and air bombardment began all along the front of the 24th, 1st Guards and 66th armies. But even on the main lines of advance the density of the artillery fire was not great and did not yield the necessary results. The attack began after Katyusha volleys.<ref>{{Cite book |title=Marshal of Victory: The Autobiography of General Georgy Zhukov |isbn=978-1-78159-291-5 |pages=807 |last1=Zhukov |first1=Georgiĭ Konstantinovich |date=2013 |publisher=Pen & Sword Military }}</ref>

By the end of 1942, 57 regiments were in service—together with the smaller independent battalions, this was the equivalent of 216 batteries: 21% BM-8 light launchers, 56% BM-13, and 23% M-30 heavy launchers. By the end of the war, the equivalent of 518 batteries were in service.<ref name=Zaloga-1984-155 />