Katyusha rocket launcher

The Katyusha is a type of rocket artillery first built and fielded by the Soviet Union in World War II. Multiple rocket launchers such as these deliver explosives to a target area more intensively than conventional artillery, but with lower accuracy and requiring a longer time to reload. They are fragile compared to artillery guns, but are cheap, easy to produce, and usable on almost any chassis. The Katyushas of World War II, the first self-propelled artillery mass-produced by the Soviet Union, were usually mounted on ordinary trucks. This mobility gave the Katyusha, and other self-propelled artillery, another advantage: being able to deliver a large blow all at once, and then move before being located and attacked with counter-battery fire.
Having been designed in 1940, katyusha weapons of World War II included the BM-13 launcher, light BM-8, and heavy BM-31. Today, the nickname Katyusha is also applied to newer truck-mounted post-Soviet – in addition to non-Soviet – multiple-rocket launchers, notably the common BM-21 Grad and its derivatives.

Nickname

Initially, concerns for secrecy kept the military designation of the Katyushas from being known by the soldiers who operated them. They were called by code names such as Kostikov guns, after A. Kostikov, the head of the RNII, the Reactive Scientific Research Institute, and finally classed as Guards Mortars. The name BM-13 was only allowed into secret documents in 1942, and remained classified until after the war.
Because they were marked with the letter K, Red Army troops adopted a nickname from Mikhail Isakovsky's popular wartime song, "Katyusha", about a girl longing for her absent beloved, who has gone away on military service. Katyusha is the Russian equivalent of Katie, an endearing diminutive form of the name Katherine. Yekaterina is given the diminutive Katya, which itself is then given the affectionate diminutive Katyusha.
German troops coined the nickname "Stalin's organ", after Soviet leader Joseph Stalin, comparing the visual resemblance of the launch array to a pipe organ, and the sound of the weapon's rocket motors, a distinctive howling sound which terrified the German troops, adding a psychological warfare aspect to their use. Weapons of this type are known by the same name in Denmark, Finland, France, Norway, the Netherlands and Belgium, Hungary, Spain and other Spanish-speaking countries as well as in Sweden.
The heavy BM-31 launcher was also referred to as Andryusha.

World War II

Katyusha rocket launchers, which were built in Voronezh, were mounted on many platforms during World War II, including on trucks, artillery tractors, tanks, and armoured trains, as well as on naval and riverine vessels as assault support weapons. Soviet engineers also mounted single Katyusha rockets on lengths of railway track to serve in urban combat.
The design was relatively simple, consisting of racks of parallel rails on which rockets were mounted, with a folding frame to raise the rails to launch position. Each truck had 14 to 48 launchers. The M-13 rocket of the BM-13 system was long, in diameter and weighed.
The weapon is less accurate than conventional artillery guns, but is extremely effective in saturation bombardment. A battery of four BM-13 launchers could fire a salvo in 7–10 seconds that delivered 1.4 tonnes of high explosives over a impact zone, making its salvo roughly equivalent to that of 72 conventional artillery howitzers. With an efficient crew, the launchers could 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 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.

Development

Initial development of solid propellant rockets was carried out by Nikolai Tikhomirov at the Soviet Gas Dynamics Laboratory, with the first test-firing of a solid fuel rocket carried out in March 1928, which flew for about 1,300 meters The rockets were used to assist take-off of aircraft and were later developed into the RS-82 and RS-132 in the early 1930s led by Georgy Langemak, including firing rockets from aircraft and the ground. In June 1938, GDL's successor Reactive Scientific Research Institute began building several prototype launchers for the modified 132 mm M-132 rockets. Firing over the sides of ZIS-5 trucks proved unstable, and V.N. Galkovskiy proposed mounting the launch rails longitudinally. In August 1939, the result was the BM-13.
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. 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. 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 Germany invaded the Soviet Union in June 1941.
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. 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.
The truck-mounted Katyushas were installed on ZIS-6 6×4 trucks, as well as the two-axle 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 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, and more than 1,800 of this model were manufactured by the end of World War II. After World War II, BM-13s were based on Soviet-built ZIS-151 trucks.
The 82 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 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. In 1942, the team of scientists Leonid Shvarts, Moisei Komissarchik and engineer Yakov Shor received the Stalin Prize for the development of the BM-8-48
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, instead of a launch rail mounted on a truck. In 1944 it became the basis for the BM-31-12 truck-mounted launcher.
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 switch to a new position some 10 km away due to the ease with which the battery could be identified by the enemy. Three batteries were combined into a division, and three divisions into a separate mine-firing regiment of rocket artillery.

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 as well as on the T-40 tank and on the STZ-3 artillery tractor.
Chassis for the launchers included:

Soviet-built ZIS-5, ZIS-6, GAZ-AA trucks, and post war the ZIS-151
STZ-5 tracked artillery tractor
T-40 tank
Lend-lease provided Studebaker US6 truck
Armored train car
River boat
Towed sledge
Towed trailer
Backpack

Weapon	Caliber	Tubes/ rails	Chassis
BM-8	82	1	Improvised vehicle mount, towed trailer or sled
M-8-6	82	6	Towed trailer or sled
BM-8-8	82	8	Willys MB jeep
M-8-12	82	12	Towed trailer or sled
16-M-8	82	16	Project 1125 armored river boat
BM-8-24	82	24	T-40 light tank, T-60 light tank
24-M-8	82	24	Project 1125 armored river boat
BM-8-36	82	36	ZIS-5 truck, ZIS-6 truck
BM-8-40	82	40	Towed trailer, GAZ-AA truck
BM-8-48	82	48	ZIS-6 truck, Studebaker US6 U3 truck, rail carriage
BM-8-72	82	72	Rail carriage
BM-13	132	24	ZIS-6 truck, improvised vehicle mount, towed trailer or sled
6-M-13	132	6	Project 1125 armored river boat
BM-13-16	132	16	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
M-20-6	132	6	static launching rail
M-30-4	300	4	static launching rail, in 1944 also available with 2x4 launching rails
M-31-4	300	4	static launching rail, in 1944 also available with 2x4 launching rails
BM-31-12	300	12	Studebaker US6 U3 truck

Weapon name	Caliber	Warhead kg	Maximum range m
M-8	82
M-13	132
M-13DD	132
M-13UK	132
M-20	132
M-30	300
M-31	300
M-31UK	300

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