Munitions

SS-60 Mk4 Cluster Rocket

Also known as
  • SS-60
  • SS-60 Mk4
  • ASTROS SS-60
  • ASTROS SS-60 Mk4
  • Brazilian SS-60 cargo rocket

The SS-60 Mk4 is a Brazilian 300 mm ASTROS-family unguided artillery rocket made by Avibras for long-range area fires. In the 2014 Yemen Civil War, open-source investigations identified SS-60 Mk4-marked rocket remnants and Brazilian ASTROS cluster munition rockets after Saudi-led coalition strikes in Saada governorate.

SS-60 Mk4 Cluster Rocket, 300 mm unguided cluster artillery rocket, Munitions
Image source: Commons Avibras ASTROS-II SS-30 Launch Image

Role in Conflicts

Profile / Specs

Profile

Origin
Brazil
Type
300 mm unguided cluster artillery rocket
Service note
ASTROS II export-service rocket documented in Yemen from 2015
Designer
Avibras Industria Aeroespacial SA
Designed
ASTROS II family developed from the early 1980s
Produced
ASTROS II rocket family production from the 1980s

Specifications

Caliber
300 mm
Length
About 5.6 m
Weight
About 595 kg
Warhead
Cluster/cargo warhead with up to 65 dual-purpose submunitions
Guidance
Unguided ballistic rocket
Range
About 20-60 km for SS-60
Launch platform
ASTROS II multiple launch rocket system; one SS-60 rocket per reload box, four 300 mm rockets per launcher load
Variants

The SS-series designations belong to the modular ASTROS rocket family. The Yemen evidence is specific to SS-60 Mk4 markings in some remnants, while other reporting could only narrow cargo-rocket remnants to the SS-60 or SS-80 family.

VariantConfigurationDesignation notes
SS-80Longer-range 300 mm ASTROS rocket

ARES treated some Yemen remnants as SS-60 or SS-80 cargo rockets where exact rocket length could not be confirmed from available imagery.

Sources: Brazilian SS-60 Cargo Rockets Employed in Yemen

Launch Platform

The SS-60 Mk4 is documented as an ASTROS-family rocket; the launcher record carries the broader vehicle, fire-control, and rocket-pod context.

LauncherLauncher typeLaunch evidence
ASTROS II, Wheeled multiple launch rocket system, ArtilleryASTROS IIWheeled multiple launch rocket system

ASTROS II launchers fire modular rocket loads including 300 mm SS-60-class rockets, and Yemen investigations connect Brazilian ASTROS cluster rockets with SS-60/SS-80 cargo-rocket remnants.

Sources: ASTROS II Weapon System, ASTROS Rocket Family, Brazilian SS-60 Cargo Rockets Employed in Yemen

Cluster Rocket Context

This entry is narrower than the full ASTROS II launcher page: it tracks the SS-60 Mk4-marked 300 mm cargo rocket evidence and related Brazilian ASTROS cluster-rocket reporting.

TopicCatalog significance
Rocket familyThe SS-60 sits in the 300 mm ASTROS rocket family, with WeaponSystems.net listing unguided ballistic flight, roughly 20-60 km range, and cargo-warhead options.
Conflict evidenceARES identified SS-60 Mk4 markings in Yemen remnants, while Amnesty and HRW documented Brazilian ASTROS cluster munition rockets in Saudi-led coalition strikes in Saada governorate.
Cluster-munition statusThe Monitor describes Brazil as a producer, stockpiler, and exporter of cluster munitions and identifies Avibras ASTROS surface-to-surface rockets with submunition warheads.
Timeline

SS-60 Mk4 Cluster Rocket Key Events

  1. ASTROS rocket family enters export service

    Avibras developed the ASTROS II family around modular launch boxes for several rocket calibers, including the 300 mm SS-60/SS-80 class.

    Sources: ASTROS II Weapon System, ASTROS Rocket Family

  2. Amnesty reports Brazilian cluster-munition evidence in Yemen

    Amnesty International reported suspected Saudi-led coalition use of Brazilian ASTROS cluster munitions after a Saada governorate attack.

    Sources: Yemen: Brazilian Cluster Munitions Suspected in Coalition Attack

  3. HRW documents further ASTROS cluster rocket remnants

    Human Rights Watch reported Brazilian-made ASTROS cluster munition rocket remnants after a February 2017 farm strike in northern Yemen.

    Sources: Yemen: Cluster Munitions Wound Children

Media

SS-60 Mk4 Cluster Rocket Videos

SS-60 Mk4 Cluster Rocket Images

SS-60 Mk4 Cluster Rocket, 300 mm unguided cluster artillery rocket, Munitions - view 1
Source: Commons ASTROS-2 Launcher Image
SS-60 Mk4 Cluster Rocket, 300 mm unguided cluster artillery rocket, Munitions - view 2
Source: Commons ASTROS-II MLRS Launch Image
SS-60 Mk4 Cluster Rocket, 300 mm unguided cluster artillery rocket, Munitions - view 3
Source: Commons Brazilian ASTROS II Launchers Image
Related Weapon Systems
ZP-39 submunition, Dual-purpose improved conventional munition submunition, MunitionsMunitionsZP-39 submunitionDual-purpose improved conventional munition submunitionThe ZP-39 is an unidentified dual-purpose improved conventional munition submunition associated with ground-fired cluster munitions and a red ribbon arming or stabilizing component. Human Rights Watch connected ZP-39 remnants to Islamic State attacks near Kobani in Syria and to an April 2015 Baqim incident in Yemen, while repeatedly noting that the producer, country of origin, and exact delivery system were not publicly known.
Sakr-6 multiple rocket launcher, Light 122 mm multiple rocket launcher, ArtilleryArtillerySakr-6 multiple rocket launcherLight 122 mm multiple rocket launcherThe Sakr-6 is a light six-tube 122 mm multiple rocket launcher associated with Egypt's Sakr/Grad-compatible rocket-artillery family. Oryx lists the type in both pre-war Yemeni Army inventories and later Houthi-held Yemen Civil War equipment, while technical sources support only family-level details for compatible Sakr and Russian-pattern Grad rockets rather than a complete Sakr-6 datasheet or a verified Sakr-6 firing incident.

Sources

Yemen: Cluster Munitions Wound ChildrenPublisher: Human Rights Watch | Note: Supports 2014 Yemen Civil War direct use: Saudi-led coalition forces used Brazilian ASTROS cluster munition rockets in Yemen, and Saudi Arabia and Bahrain had purchased ASTROS cluster munition rockets from Brazil. | Accessed: 2026-06-20Yemen: Brazilian Cluster Munitions Suspected in Coalition AttackPublisher: Amnesty International | Note: Supports 2014 Yemen Civil War direct use: Saudi Arabia-led coalition forces appear to have used Brazilian cluster munitions in Saada in October 2015. | Accessed: 2026-06-20Brazilian SS-60 Cargo Rockets Employed in YemenPublisher: Armament Research Services | Note: Supports 2014 Yemen Civil War direct use: SS-60 Mk4-marked remnants were fielded or fired in strikes in Saada governorate; also supports Avibras manufacturer background. | Accessed: 2026-06-20ASTROS II Weapon SystemPublisher: U.S. Army ODIN | Note: Supports ASTROS II system background, launcher family context, and technical classification. | Accessed: 2026-06-20ASTROS Rocket FamilyPublisher: WeaponSystems.net | Note: Supports SS-60 specifications including caliber, length, weight, unguided ballistic flight, submunition warhead, and range. | Accessed: 2026-06-20The Monitor Brazil Cluster Munition Ban PolicyPublisher: Landmine and Cluster Munition Monitor | Note: Supports background on Brazil as a cluster-munition producer, stockpiler, and exporter, and identifies Avibras ASTROS surface-to-surface rockets with submunition warheads. | Accessed: 2026-06-29Commons Avibras ASTROS-II SS-30 Launch ImagePublisher: Wikimedia Commons | Note: Supports image provenance for a public-domain ASTROS II launch image used as rights-clear visual context for the SS-60 Mk4 rocket family. | Accessed: 2026-06-20Commons ASTROS-2 Launcher ImagePublisher: Wikimedia Commons | Note: Supports image provenance for a public-domain ASTROS II launcher image used as rights-clear visual context. | Accessed: 2026-06-20Commons ASTROS-II MLRS Launch ImagePublisher: Wikimedia Commons | Note: Supports image provenance for a public-domain ASTROS II rocket-launch image used as rights-clear visual context. | Accessed: 2026-06-20Commons Brazilian ASTROS II Launchers ImagePublisher: Wikimedia Commons | Note: Supports image provenance for a CC BY 2.0 image of Brazilian ASTROS II launchers. | Accessed: 2026-06-20