Self-propelled anti-aircraft weapon

(Redirected from Self-propelled anti-air)

An anti-aircraft vehicle, also known as a self-propelled anti-aircraft gun (SPAAG) or self-propelled air defense system (SPAD), is a mobile vehicle with a dedicated anti-aircraft capability.

A Soviet-made ZSU-23-4 "Shilka" in California during a USMC exercise, 1997

Specific weapon systems used include machine guns, autocannons, larger guns, or surface-to-air missiles, and some mount both guns and longer-ranged missiles (e.g. the Pantsir-S1). Platforms used include both trucks and heavier combat vehicles such as armoured personnel carriers and tanks, which add protection from aircraft, artillery, and small arms fire for front line deployment.

Anti-aircraft guns are usually mounted in a quickly-traversing turret with a high rate of elevation, for tracking fast-moving aircraft. They are often in dual or quadruple mounts, allowing a high rate of fire. In addition, most anti-aircraft guns can be used in a direct-fire role against surface targets to great effect. Today, surface-to-air missiles (generally mounted on similar turrets) have largely supplanted anti-aircraft guns, but they may return as a cheap way to counter unmanned aerial systems (drones), cruise missiles, and ultralight aircraft.

History

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World War I

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A World War 1, British, truck-mounted, QF 3 inch gun

Anti-aircraft machine guns have long been mounted on trucks, and these were quite common during World War I. A predecessor of the WWII German "88" anti-aircraft gun, the WWI German 77 mm anti-aircraft gun, was truck-mounted and used to great effect against British tanks.

The British QF 3 inch 20 cwt was mounted on trucks for use on the Western Front. The British also had a first dedicated anti aircraft weapon, the QF 1-pounder pom-pom. Mounted on an armoured truck titled the Pierce-Arrow armoured AA lorry, which was produced in limited numbers and only seeing service throughout 1915. Towards the end of the war Germany produced three prototype SPAAGs with AA guns mounted on A7V chassis known as the A7V Flakpanzer.[1]

Inter-war period

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Between the two World Wars, the United Kingdom developed the Birch gun, a general-purpose artillery piece on an armoured tracked chassis capable of maintaining formation with their current tanks over terrain. The gun could be elevated for anti-aircraft use.

 
Vickers Armstrong "Type 76" SPAAG loaded onto a train.

The first tracked SPAAG-design to be manufactured in series was most likely the British/Siamese Vickers Armstrong "Type 76" (per Buddhist year 2476 = 1933 CE), as named by the Royal Siamese Army, a SPAAG based on the chassis of the Dragon, Medium, Mark IV artillery tractor (Vickers Mk.E 6-ton light tank derivative), mounting a revolving Vickers 40 mm QF 2 pounder pom-pom autocannon in an open fighting compartment. About 26 were sold to Siam in 1932 and saw action as infantry support guns and AA guns during the Franco-Thai war (1940–1941) along with 30 Vickers Mk.E Type B 6-ton tanks. Despite being the first tracked SPAAG en masse, the open-top design of the Vickers Type 76 made it outdated even by the early 1930s.

 
Landsverk L-62 Anti-prototype in 1939.

The first modern SPAAG to be produced was most likely the Swedish Landsverk L-62 Anti in 1936, featuring a tracked armoured body with a revolving turret, a so-called anti-aircraft tank. It was based on a widened chassis of the Landsverk L-60 light tank and was armed with a Bofors 40 mm Automatic Gun L/60 in an open-top revolving turret. The design was bought by Hungary just prior to the war and Finland ordered a refined model in 1941, known as the Anti II.

By the late 1930s, the British had developed a version of the Mk.VI Light Tank armed with four machine guns that were known as Light Tank AA Mk.I, and also a twin 15 mm version based on the Light Tank Mk.V was built. Among early pre-war pioneers of self-propelled AA guns were the Germans. By the time of the war, they fielded the Sd.Kfz. 10/4 and Sd.Kfz. 6/2, cargo half-tracks mounting single 20 mm or 37 mm AA guns (respectively). Later in the war similar German half-tracks mounted quadruple 20 mm weapons.

World War II

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German Flakpanzer IV "Wirbelwind" - a 20 mm Flakvierling quadmount on a Panzer IV chassis.

Larger guns followed on larger trucks, but these mountings generally required off-truck setup in order to unlimber the stabilizing legs these guns needed. One exception to this rule was the Italian Cannone da 90/53 which was highly effective when mounted on trucks, a fit known as the "autocannoni da 90/53". The 90/53 was a feared weapon, notably in the anti-tank role, but only a few hundred had been produced by the time of the armistice in 1943.

Other nations tended to work on truck chassis. Starting in 1941, the British developed the "en portee" method of mounting an anti-tank gun (initially a 2 pounder) on a truck. This was to prevent the weapon from being damaged by long-distance towing across rough, stony deserts, and it was intended only to be a carrying method, with the gun unloaded for firing. However, crews tended to fire their weapons from their vehicles for the mobility this method provided, with consequent casualties. This undoubtedly inspired their Morris C9/B (officially the "Carrier, SP, 4x4, 40 mm AA"), a Bofors 40 mm AA gun mounted on a chassis derived from the Morris "Quad" Field Artillery Tractor truck. Similar types, based on 3-ton lorries, were produced in Britain, Canada and Australia, and together formed the most numerous self-propelled AA guns in British service.

The U.S. Army brought truck-towed Bofors 40 mm AA guns along with truck-mounted units fitted with mechanized turrets when they sailed, first for Great Britain and then onto France. The turrets carried four .50 inch (12.7 mm) machine guns, which were designed to be adjusted to converge at the single point where enemy aircraft were expected to appear at low altitude in conduction of strafing runs directed at large infantry and field artillery units.

Interest in mobile AA turned to heavier vehicles with the mass and stability needed to easily train weapons of all sizes. Probably the desire, particularly in German service, for anti-aircraft vehicles to be armoured for their own protection also assisted this trend.

 
40M Nimrod anti-aircraft battery.

The concept of using armored SPAAG (anti-aircraft tanks) en masse was pioneered by Hungary during World War II with the production of the 40M Nimrod, a license-produced version of the previously mentioned late 1930s Landsverk L-62 Anti I SPAAG. Germany followed later with their "Flakpanzer" series. German World War II SPAAGs include the Möbelwagen, Wirbelwind, Ostwind and Kugelblitz. Other forces followed with designs of their own, notably the American M16 created by mounting quadruple M2HB Browning machine guns on a M3 Half-track.

The British developed their own SPAAGs throughout the war mounting multiple machine guns and light cannon on various tank and armoured car chassis and by 1943, the Crusader AA tanks, which mounted the Bofors 40 mm gun or two-three Oerlikon 20 mm cannon. Although used during the Normandy landings, by that point German aircraft were contained by the Allies own air forces and they were largely unneeded.

Cold War and later

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Czechoslovak self-propelled anti-aircraft gun M53/59 Praga developed in the late 1950s.
 
Flakpanzer Gepard, combining radars, fire control and two 35 mm guns in a new turret mounted on a Leopard chassis.
 
Typical of more modern designs, the Tunguska-M1 mounts both missiles and cannons.

The introduction of jet engines and the subsequent rough doubling of aircraft speeds greatly reduced the effectiveness of the SPAAG against attack aircraft.[dubiousdiscuss] A typical SPAAG round might have a muzzle velocity on the order of 1,000 metres per second (3,300 ft/s) and might take as long as two to three seconds to reach a target at its maximum range. An aircraft flying at 1,000 kilometres per hour (620 mph) is moving at a rate of about 280 metres per second (920 ft/s). This means the aircraft will have moved hundreds of meters during the flight time of the shells, greatly complicating the aiming problem to the point where close passes were essentially impossible to aim using manual gunsights. This speed also allowed the aircraft to rapidly fly out of range of the guns; even if the aircraft passes directly over the SPAAG, it would be within its firing radius for under 30 seconds.

SPAAG development continued through the early 1950s with ever-larger guns, improving the range and allowing the engagement to take place at longer distances where the crossing angle was smaller and aiming was easier. Examples including the 40 mm U.S. M42 Duster and the 57 mm Soviet ZSU-57-2. However, both were essentially obsolete before they entered service, and found employment solely in the ground-support role. The M42 was introduced to the Vietnam War to counter an expected North Vietnamese air offensive, but when this failed to materialize it was used as an effective direct-fire weapon. The ZSU-57 found similar use in the Yugoslav Wars, where its high-angle fire was useful in the mountainous terrain.

By the late 1950s, the US Army had given up on the SPAAG concept, considering all gun-based weapons to be useless against modern aircraft. This belief was generally held by many forces, and the anti-aircraft role turned almost exclusively to missile systems. The Soviet Union remained an outlier, beginning the development of a new SPAAG in 1957, which emerged as the ZSU-23-4 in 1965. This system included search-and-track radars, fire control, and automatic gun-laying, greatly increasing its effectiveness against modern targets. The ZSU-23 proved very effective when used in concert with SAMs; the presence of SAMs forced aircraft to fly low to avoid their radars, placing them within range of the ZSUs.

The success of the ZSU-23 led to a resurgence of SPAAG development. This was also prompted by the introduction of attack helicopters in the 1970s, which could hide behind terrain and then "pop up" for an attack lasting only a few tens of seconds; missiles were ineffective at low altitudes, while the helicopters would often be within range of the guns for a rapid counterattack. Notable among these later systems is the German Gepard, the first western SPAAG to offer performance equal to or better than the ZSU. This system was widely copied in various NATO forces.

SPAAG development continues, with many modern examples often combining both guns and short-range missiles. Examples include the Soviet/Russian Tunguska-M1, which supplanted the ZSU-23 in service, the newer versions of the Gepard, the Chinese Type 95 SPAAA, and the British Marksman turret, which can be used on a wide variety of platforms. Some forces, like the US Army and USMC have mostly forgone self-propelled guns in favor of systems with short-range infrared-guided surface-to-air missiles in the AN/TWQ-1 Avenger and M6 Linebacker, which do not require radar to be accurate and are generally more reliable and cost-effective to field, though their ability to provide ground support is more limited. The U.S. Army did use the M163 VADS and developed the prototype design of the M247 Sergeant York.

Present day

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Modern SPAAGs usually have short-range missiles for longer range engagement. The Pantsir system from Russia is primarily a missile battery, although it does have twin cannons as secondary armament.

Some examples of modern SPAAG:

Model Manufacturer Image Origin Platforms Weapons Caliber and ammunitions Number built Notes
CS/SA5 SPAAG Norinco   China Type 08 1 × Gatling gun (6 barrels)

2 × FN-6A

30 × 113 mm

[2][3]
PGZ-95 SPAAA Norinco     China 4 × PG-87

4 × QW-2 IR missiles

25 x 183 mmB ~ 270

[4]

[5]
PGZ-04/A SPAAA 4 × Type 87

4 × FN-6 IR missiles

Upgraded variant of PGZ-95 SPAAA[5]
PGZ-09 SPAAA Norinco     China PLZ-05 chassis 2 × PG99

[note 1]

35 x 228 mm [de] [6][7]
PGZ 625

PGL-XX (Code name 625)

Norinco   China Type 08 1 × Gatling gun (6 barrels)

4 to 8 × FN-16 (for PGZ 625E)

25 × 287 mm [8][9]
RAPIDFire 40 [fr] KNDS France

Thales

    France 40CTAS autocanon 40 × 255 mm

A3B-T programmed telescoped ammunition

Naval air-defence gun installed on truck[10][11]
Machbet IAI

(Israeli Aircraft Industries)

    Israel M113 1 × M61A1 Vulcan Gatling gun (6 barrels)

4 × FIM-92 Stinger

20 × 102 mm

Entered service in 1997, retired in 2006 [12]
DRACO B1 CIO

(Consortium Iveco OTO Melara)

    Italy Freccia 1 × Cannone 76/62 OTO-Breda Super Rapido 76 × 636 mmR 1 Only prototype[13]
OTOMATIC

"OTO Main Anti-aircraft Tank for Intercept and Combat"

OTO-Melara     Italy Hulls of the: 1 × Cannone 76/62 OTO-Breda Super Rapido 76 × 636 mmR 2 [14]
SIDAM 25 OTO Breda     Italy M113 4 × Oerlikon KBA 25 × 137 mm 275 [15]
Stryker M-SHORAD

"Maneuver Short Range Air Defense"

Leonardo DRS     Italy  United States Stryker 1 × XM914 (M230LF chain gun)

1 M240 (7.62mm)

4 × FIM-92 Stinger

2 × AGM-114L Hellfire

30 × 113 mm

7.62 × 51 mm

312 to 361

[16]

[17]
Type 87 SPAAG MHI

(Mitsubishi Heavy Industries)

    Japan Type 74 tank 2 × Oerlikon KDA

[note 2]

35 x 228 mm [de]

HEI ammunition

52 [18]
Kongsberg RS6

MADIS RWS

"Marine Air Defense Integrated System US Marine Corps Ground Based Air Defense"

Kongsberg   Norway Oshkosh JLTV 1 × XM914E1 (M230LF chain gun)

1 × M240C (7.62mm)

2 × Air-to-Air Stinger

30 × 113 mm

7.62 × 51 mm

Future USMC SHORAD system[19][20]
PZA Loara Radwar [pl]     Poland T-72M chassis 2 × Oerlikon KDA

[note 2]

35 x 228 mm [de]

HEI ammunition

2 - 4 [21]
SA-35 PIT-RADWAR

PGZ

(Polska Grupa Zbrojeniowa)

  Poland Jelcz 6×6 1 × Oerlikon KDA 35 x 228 mm

Air burst programmable rounds

[22]

Developed from AM-35K naval gun.

ZSU-23-4MP Biała ZMT SA

(Zakłady Mechaniczne Tarnów)

    Poland 4 × AZP-23

4 × Grom IR missiles

23 × 152 mm

~ 70 Polish modernised variant [23]
Mangart 25 Valhalla Turrets     Slovenia Oshkosh JLTV 1 × Oerlikon KBA

1 × FN MAG

Option for short-range IR missiles

25 × 137 mm

7.62 × 51 mm

[24]
K263 Cheongoong SPAAG Doosan     South Korea K200A1 KIFV 1 × KM167 A1 VADS

Gatling gun (6 barrels)

20 × 102 mm 200 [25]
K30 Bi Ho

"Flying Tiger"

Doosan     South Korea K200A1 KIFV 2 × Oerlikon KCB 30 × 170 mm 176 [25]
K30 Bi Ho Hybrid

"Flying Tiger"

Hanwha Aerospace

LIG Nex1

    South Korea K808 White Tiger 2 × Oerlikon KCB

2 × LIG Nex1 Chiron

30 × 170 mm

[26][27]
K30 Bi Ho II

"Flying Tiger"

Joint Venture

Hanwha Aerospace

SAMI (Saudi Arabian Military Industries)

  South Korea   Saudi Arabia K808 White Tiger 1 × Oerlikon KCB-B

4 SAM

30 × 170 mm

Air burst programmable munitions

In development [28]
Lvkv 9040

Luftvärnskanonvagn 9040

BAE Systems Bofors     Sweden CV90 1 × 40 mm Bofors L/70B autocanon 40 × 365 mm 30 [29][30]
Tridon Mk2 BAE Systems Bofors     Sweden Scania 6×6 truck 1 × Bofors 40 Mk4 naval gun Autocanon 40mm L/7'0 40 × 365 mm

Air burst programmable munitions FUZE 3P

Naval gun installed on truck, prototype of 2024.[31][32]
Flakpanzer Gepard Oerlikon Contraves

Siemens-Albis [de]

Krauss-Maffei

     Switzerland  Germany 2 × Oerlikon KDA

[note 2]

35 x 228 mm [de]

HEI ammunition

570

[34]

[35][36]
Flakpanzer Gepard 1A2   2 × Rheinmetall KDG 35/1000 [de]

[note 3]

35 x 228 mm

Airburst programmable rounds AHEAD

Skyranger 30 Rheinmetall Air Defence (Oerlikon)  

 

   Switzerland  Germany Oerlikon KCE

Option for short-range IR missiles (FIM-92 Stinger or Mistral)

30 × 173 mm

Air burst programmable rounds AHEAD

55 ordered

(15 planned, 9 in option)

[38][39][40][41]

[42][43][44]
Skyranger 35 Rheinmetall Air Defence (Oerlikon)      Switzerland  Germany 1 × Rheinmetall KDG 35/1000 [de]

[note 3]

35 x 228 mm

Air burst programmable rounds AHEAD

Turret based on Skyshield / MANTIS[42]
GÜRZ Aselsan   Turkey Seyit 8×8 (Anadolu Savunma) 1 × KDC-02

4 × Bozdoğan IR missile

35 x 228 mm [de]

ATOM airburst

Comparable to Pantsir, in development[45]
KORKUT Aselsan  

(Turret adapted to land platform)

  Turkey 2 × KDC-02

[note 4]

35 x 228 mm [de]

ATOM airburst

13 [46]
Marksman Marconi Electronic Systems     United Kingdom 2 × Oerlikon KDA

[note 2]

35 x 228 mm [de]

HEI ammunition

7 [47][48]
LAV-AD General Dynamics Armaments Systems     United States LAV II

(chassis of LAV-25)

1 × GAU-12/U Gatling gun (5 barrels)

2 × pods with 4 × FIM-92 Stinger each

25 × 137 mm

17 Used for a short period by the USMC[49]

See also

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Footnotes

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  1. ^ License produced Oerlikon GDF-002 by China.
  2. ^ a b c d Canon used on the GDF-001, GDF-002, GDF-003 and GDF-005, without programmable ammunition capacity, using HE rounds.[33]
  3. ^ a b Canon used since Oerlikon GDF-006 series with AHEAD programmable ammunition capacity.[37]
  4. ^ License produced Oerlikon GDF-002 by MKE using the programmable ATOM 35mm ammunition.

References

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