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Manufactured explosive weapons

What is a grad?

Syrian rebel BM-21 launcher launching rockets in Syrian Desert (by Qasioun News Agency and licensed under CC BY 3.0)

What is a Grad?

Developed in the 1960s, the BM-21 Grad has become the most numerous and widely-deployed multiple launch rocket system (MLRS) in the world. Given the fact that a single launcher is capable of firing a full salvo of 40 122mm rockets over a wide area in under 20 seconds, the name ‘Grad’ – the Russian word for ‘hail’ – is fitting. The Grad’s simple design and ability to distribute a large explosive payload in a short space of time has led to it being heavily adopted, copied and adapted over the past 60 years. 

The History of the Grad MLRS

Development

The BM-21 emerged as a descendant of the Soviet 132mm BM-13 ‘Katyusha’ rocket launcher – famously nicknamed ‘Stalin’s Organ’ by German troops in WWII. The BM-13 came into active service shortly after Operation Barbarossa and proved startlingly effective at delivering overwhelming firepower and crushing enemy morale. During the war and in the years following, the USSR continued to develop and improve ‘BM’ (which stands for ‘Боевая Машина or ‘Combat Vehicle’) MLRSs and, in 1952, the Soviet Army adopted the BM-14 – capable of launching a salvo of 16 140mm rockets – as the BM-13’s replacement.

Eight years later, development on the BM-21 Grad began. Whilst showing similarities to the BM-13 and BM-14, the Grad had a number of key differences from its predecessors. Most notable was the use of launch tubes to hold rockets, rather than the rails that had come before. Furthermore, mounted on the Ural-375D 6×6 truck, the Grad could fire forty 122mm rockets with an advanced range and explosive payload.

First use

Now the world’s most common MLRS, the BM-21 Grad was first used during Sino-Soviet border clashes in March 1969. Chinese forces captured the disputed Zhenbao (Damansky) Island from Soviet border guards, leading to a series of skirmishes along the Ussuri (Wusuli) River. Following an emergency meeting of the Politburo, and the personal approval of Brezhnev, the top-secret BM-21 Grad was deployed – alongside the T-62 tank – to devastate Chinese positions on the islan

Recent developments and modifications

There has been little change to the design integrity of the full MLRS system since its first use in 1969. However, there have been several developments to the original Grad to incorporate newer technologies and modify elements for differing purposes. For example, the BM-21-1 and the 2B17M Tornado-G both emerged as modernised versions of the 40-tube 122mm Grad MLRS, boasting enhanced features – albeit with a largely unchanged design.

ModelBM-21-1.
First appeared – 1978.
Mounted on – Ural-4320 6×6 chassis.
Difference from original 1964 Grad – Highly similar system, but includes greater protection over launch tubes.

Model2B17M Tornado-G.
First appeared – 1998.
Mounted on – Ural-4320 6×6 chassis.
Difference from original 1964 Grad – Similar dimensions to the original Grad, but fully automatic, with a remote fuse setting system and satellite navigation. Considered to be three times more effective than the BM-21 Grad.

A number of more specialised systems have also emerged such as the 12-tube BM-21V. This variant, mounted on a 4×4 Gaz-66B light truck, was designed to support airborne units and is capable of being dropped from the air into conflict zones. Another example is the 40-tube BM-21PD which was developed in 1980 for the protection of naval bases. This model incorporates rockets that function like depth charges and can be used against small submarines and combat divers. 

It is also important to mention the BM-21P (Partizan) bipod-mounted single tube launcher, developed for Spetsnaz forces. Although this fires a single, modified rocket and cannot be classified as an MLRS, it has been widely proliferated around the world particularly amongst paramilitary and guerrilla forces. Its use remains popular today due to its simplicity, low-cost and adaptability.

BM-21 Grad in Kiev, Ukraine (by Qypchak and licensed under CC BY-SA 3.0)

What are, broadly, the different types of Grad? 

Alongside more recent, Russian-made developments and modifications, the BM-21 has been widely copied and adapted by weapon manufacturers outside Russia. Currently 122mm MLRSs are produced in at least 15 different countries throughout the world – the majority of these systems show few discernible features from the Russian original. Some models, such as the Chinese-made Type-81, exist as straight copies of the BM-21. The system was reverse engineered after being captured during the Sino-Vietnamese War. Others have been developed using parts and technologies purchased from Russia, to build highly similar models. 

Producers of 122mm MLRSs – most are close copies of the original BM-21 “Grad” (data taken from The Military Balance 2020).

Examples have also emerged of improvised Grad systems. Typically these are constructed by rebel groups using captured parts and differ widely from model to model. Such improvised systems are likely to be extremely inaccurate, lacking any standardisation in design, and typically mounted on vehicles much lighter than manufactured 122mm MLRSs.

Alongside an assortment of globally produced 122mm launchers, there is also some diversity in the type of rockets used by these systems. The original Russian-made 9M22 – delivering a high-explosive fragmentation warhead up to 20km – remains the most commonly used munition with 122mm MLRSs throughout the world. However, there exists a myriad of other Russian-made rockets, which differ in size, range, and the explosive they deliver.

Different types of Russian-made 122mm rockets (taken from O. Dullum, Rocket Artillery Reference Book).

Several other countries including Turkey, China and Pakistan also produce their own 122mm rockets, compatible with Grad systems or similar variants. It is worth noting however, that the majority of munitions used by 122mm MLRSs are copies, or closely similar, to the 9M22. 122mm rockets are also capable of being launched without Grad, or Grad-style, systems. Rockets can be propped up by simple frames – or sometimes just rocks – and fired at full range with greatly reduced accuracy. 

What are the typical dimensions and weight of a Grad (i.e. from largest to smallest)?

A full BM-21 Grad MLRS comprises three main components – rockets, launcher and vehicle. Fully assembled, and loaded with 40 rockets, a BM-21 Grad system, mounted on a Ural-375D or Ural-4320 6×6 truck, weighs 13.7 tonnes, is 7.35m long, 2.4m wide and 3.09m high

Most other variants of the BM-21 Grad have similar weights and dimensions to the original they mimic. There are certain exceptions. The Jobaria or Jahanam Launcher used by forces in the United Arab Emirates (UAE), is much, much larger, comprising 240 launch tubes mounted on a 8×8 truck.  

In terms of rocket munitions, the 9M22 – the most commonly used rocket by 122mm MLRSs – is 2.87m in length, weighing 66kg. Other 122mm rockets compatible with Grad systems range from 1.5m to 3.3m in length and from 27kg to 71.6kg in weight. However, smaller rockets are generally used with portable systems, rather than full MLRSs, and the majority of commonly used rockets are 2.5-3m and 65-70kg.

What quantity of explosives can Grads deliver?

The 9M22 122mm rocket contains 6.4kg of TGAF-5 explosive comprising 40% TNT, 40% RDX, 17% aluminium powder and 3% phlegmatizer. 

The combined weight of the entire warhead is 18.4kg, with a net explosive quantity of 8.32kg. The majority of commonly produced 122mm rockets have a warhead weighing between 18 and 25kg, although some models, such as those which carry cluster munitions, weigh over 30kg.

Due to its ability to fire a salvo of 40 rockets in a very short space of time, a full Grad system is able to deliver approximately 256kg of explosive over a wide area in only 20 seconds – compounding the explosive damage that a single rocket is capable of producing.

What is the range of a Grad?

A Grad’s range is determined by the rocket it fires, not the launcher itself. The commonly used 9M22 rocket has a maximum range of 20.75km; however, in recent years 122mm rockets with improved range have been developed. Examples include the Russian-made 9M521 and the Turkish-made TR-122, both of which are capable of firing at a distance between 10 and 40km. Smaller, portable munitions and those which carry a far greater amount of explosive typically have a significantly reduced range of less than 10km. 

How accurate is a Grad?

Grads are notoriously inaccurate. Accuracy refers to the ability of a weapon to hit a desired target and, as a wide-area system intended to blanket a large area on an open battlefield, Grads are not designed to hit pinpoint targets, but rather provide area coverage. 

Grad rockets are fin-stabilised and fired from grooved launch tubes which cause them to slowly rotate in flight. However, beyond this rudimentary stabilisation technique, there is very little to ensure accuracy. Grad rockets – unlike missiles – are totally unguided, meaning once fired it is not possible to adjust their direction or make alterations dependent on wind speed. This is made worse by the fact that Grad systems usually fire rockets from distances close to their maximum range of 20km. As systematic and random errors are significantly increased when a munition must travel further – primarily due to prolonged impact from meteorological conditions – Grad rockets are far less accurate than shorter-range explosive weapon types such as mortars.

For an 122mm MLRS system, random errors account for a deviation from the target of 110m x 180m, whilst systematic errors will account for a deviation of 120m x 240m. As a result, errors are likely to account for a total area of 160m x 300m, meaning any one rocket could land either 80m in front or behind its target, or 150m to either side.

Clearly when such weapons are used in or against populated areas, the risk of civilian harm is immense.

How precise is a Grad?

As well as being inaccurate, Grads are also extremely imprecise. Precision refers to the ability of a munition to hit a target consistently. Grads are designed to fire a salvo of 40 rockets over a wide area, meaning the grouping of rockets is very poor. Alongside the high error probable faced by each rocket, the fact that MLRSs are vehicle-mounted creates further issues. When rockets are fired, the vehicle’s suspension is compressed, slightly altering the angle of the launch tubes and meaning rockets fired later in the salvo are more imprecise than those fired earlier.

‘Rockets launched from an MBRL [MLRS] of a design such as the BM-21 will typically be among the least accurate or precise explosive weapon systems commonly employed’ – GICHD, ‘Explosive Weapon Effects’.

Who are the biggest manufacturers of Grads? 

Russia is the only manufacturer of BM-21 Grads and by far the largest producer of 122mm MLRSs in the world today. Since the 1960s, BM-21 Grads and their Russian predecessors have been designed and constructed by JSC NPO SLAV in Tula, Russia. 

Of the at least 9,019 globally accounted for 122mm MLRSs currently recorded by Military Balance, 5,303 (59%) are Russian-made BM-21 Grads or direct derivatives (such as the 2B17M Tornado-G). Chinese made systems, such as the Type-81, account for 25% of all recorded 122mm MLRSs. 

After that, Czech-made models such as the RM-70, RM-70 Vampir and RM-70/85 are the next most numerous, accounting for 4% of global supply. 


Biggest manufacturers of 122mm MLRSs by quantity currently in active or reserve service (data taken from The Military Balance 2020).

Where are Grads used?

Between 2011 and 2020, AOAV recorded explosive incidents involving Grad MLRSs in four countries: Azerbaijan, Libya, Syria and Ukraine. 

Number of explosive incidents involving Grad MLRSs in the last decade by country (data taken from AOAV EVM).

In Ukraine, the country worst-affected by Grad attacks in the last decade, all of the incidents recorded by AOAV took place in Eastern Ukraine in areas affected by the war in Donbass. The city of Donetsk and its surrounding areas were by far the worst hit location – AOAV recorded five incidents of Grad attacks here. The cities of Mariupol, Debaltseve and Sloviansk were also badly affected, each recording three Grad attacks in 2014 and 2015. 

AOAV also found examples of 122mm rockets (often nicknamed ‘Katyusha rockets’) used in Egypt, Iraq, Israel, Lebanon, Saudi Arabia, Sudan, Turkey and Yemen in the past ten years. However, in all these cases it could not be determined that rockets were fired from MLRSs like the BM-21 Grad. It is more likely that these were attacks using single rockets fired from basic mounts – a practice that is particularly common for poorly-funded non-state actors or those in cross border conflicts, such as Hamas and Hezbollah. Although these attacks utilise a key component of Grad MLRSs and can be highly destructive, they are beyond the scope of this article which focuses on full systems, rather than single rockets.

Who typically uses Grads?

According to The Military Balance, there are currently 81 states where 122mm MLRSs are in service. In 53 (65%) of those states, the 122mm MLRS recorded is a BM-21 Grad or similar, Russian-made model. In most cases, national armies are in possession of MLRSs, although Grads are recorded in the armouries of several non-state actors, such as the Luhansk People’s Republic (LPR) in Ukraine, and the National Front for Liberation in Syria. 

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Volume of 122mm MLRSs in active or reserve service by country (data taken from The Military Balance 2020).
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Although Grads and their copies proliferate throughout the world, AOAV has only recorded their use in four countries in the past decade. In these cases Grads were used almost in equal part by non-state and state actors. When the perpetrator was named, ‘Ukrainian separatists’ were behind the greatest number of incidents, although this labelling could refer to either the Donetsk People’s Republic (DPR) or the LPR (and could be, potentially, Russian troops deployed in the area). In Ukraine, Libya and Syria, Grad attacks were perpetrated by both state and non-state actors. 


Generally, what types of injury do Grads cause?

Grad rockets typically carry HE-FRAG warheads, which cause injury both from the initial blast wave created, and from the fragmentation emitted moments after detonation. Blast injuries are caused by the huge over-pressurisation of organs or body parts caused by the explosion. Typically this affects the ears, lungs or gastrointestinal tract and is often lethal. 

Fragmentation injury from Grad rockets is either caused by the close to 4,000 pre-made fragments that are released on impact, or from secondary fragmentation produced when debris breaks off nearby structures. Pre-made fragments will usually cause small penetration injuries, the severity of which will depend on their incidence and location on the body. Injury from secondary fragmentation is far more varied and will depend on objects and structures in the vicinity of the blast.

The nature and severity of injuries caused by Grad attacks is highly dependent on both the proximity of individuals to the blast, and the blast location. If rockets don’t fall within several metres of an individual, serious blast injuries are highly unlikely in open areas. This is because the blast wave dissipates in uncrowded spaces. However, primary fragmentation injuries may be more common in this environment, due to a lack of significant structures providing protection from flying shrapnel. 

On the other hand, serious blast injuries in built-up, populated areas are far more common. Buildings reflect and magnify blast waves rather than allowing them to dissipate. As such, whilst permanent structures are likely to provide protection from fragmentation, they increase the risk of suffering serious, or fatal, blast injuries. Furthermore, secondary fragmentation is far more common in built-up areas, where superfluous glass, brick and metal produce debris often more harmful than the Grad’s pre-made fragments. 

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Graph showing the hit probability for primary fragmentation from a single 9M22 rocket (taken from GIHCD, ‘Explosive Weapon Effects’).

What patterns of harm do Grads cause to surrounding environments and infrastructure? 

122mm Grad rockets typically contain basic fuses which detonate upon impact with a surface. When this occurs, rockets create a small crater, as well as releasing 3,920 pre-made fragments. Unlike mortars, which typically land at an angle close to 90° to the ground, rockets impact at a much flatter trajectory. As a result, the majority of fragmentation flies in front of the point of impact, rather than around it. 

Due to the size and weight of Grad rockets’ fragmentation (each fragment is less than 3g), shrapnel is unlikely to cause serious damage to permanent structures made from brick or concrete. However, any glass close to the centre of impact is normally damaged or destroyed by the blast and subsequent fragmentation. Most Grad attacks in populated areas cause widespread damage to windows and other glazing.

Buildings usually don’t suffer serious structural damage from Grad rockets unless they sustain a direct hit. Even then, the explosive quantity contained in a single rocket is unlikely to cause building collapse. As a full Grad system fires 40 unguided rockets over a wide area, Grad attacks in populated areas typically cause differing amounts of damage to a large number of buildings in a location. However, an attack would likely not raze a single building to the ground, as might be the case with a precision airstrike utilising a far greater explosive quantity. 

In environments with few permanent buildings such as make-shift markets, refugee camps or shanty towns, patterns of harm are likely to be very different. Rudimentary structures will often be completely destroyed by the initial blast wave and provide little protection from fragments – allowing shrapnel to travel far greater distances. The large amount of heat given off at the initial point of detonation may also cause fires in areas with an abundance of flammable material. 

A house in Mariupol, Ukraine which sustained a direct hit from a Grad rocket in January 2015 (Jake Tacchi).

Read about the impact of the BM-21 Grad MLRS on Mariupol, Ukraine.