Munitions

BLU-63A/B submunition

Also known as
  • BLU-63(T-1)/B
  • BLU 63B bomblet

The BLU-63A/B is a U.S.-origin impact-fired high-explosive fragmentation bomblet for the CBU-58A/B cluster bomb. Technical manuals describe the A/B round as carrying two 5-gram titanium pellets for incendiary effect, while Yemen conflict reporting ties the family to Saudi-led coalition cluster-bomb remnants.

BLU-63A/B submunition, Air-dropped high-explosive fragmentation bomblet, Munitions
Image source: BLU 63B bomblet, air-dropped

Role in Conflicts

Early Contract Pricing

GAO's review captured two early production prices for the BLU-63/B program.

DateContractorUnit priceContext
1970-06Ajax Hardware Manufacturing$0.287753-year firm fixed-price contract for 42 million bomblets.
1971-04-07Hoffman Electronics$0.35Letter contract for 23,750,600 bomblets as a second source.
Profile / Specs

Profile

Origin
United States
Type
Air-dropped high-explosive fragmentation bomblet
Service note
Late-1960s U.S. cluster munition bomblet
Designer
U.S. Air Force
Designed
Late 1966
Unit cost
$0.28775 each in the June 1970 Ajax contract
Produced
1970-1971 initial production contracts

Specifications

Diameter
2.94 in (75 mm)
Weight
0.93 pound
Explosive weight
0.25 pound
Fuzing
Impact-fired, centrifugal-armed M129 fuze
Fragmentation
Scored steel case; about 260 fragments
Variant effect
BLU-63A/B adds two 5-gram titanium pellets for incendiary effect
Carrier load
SUU-30H/B loads 650 bomblets into the CBU-58A/B
Variants
  • BLU-63/B
  • BLU-63A/B
  • BLU-63(T-1)/B training variant
Carrier Bombs

The BLU-63A/B is a submunition that appears inside the CBU-58A/B cluster-bomb family.

CarrierCarrier typeCarriage evidence
CBU-58A/B cluster bomb, Air-delivered cluster bomb, MunitionsCBU-58A/B cluster bombCluster bomb

The F-16 non-nuclear weapons delivery manual extract says the SUU-30H/B is loaded with 650 BLU-63A/B bomblets to create the CBU-58A/B.

Sources: F-16 Non-Nuclear Weapons Delivery Manual Extracts

Timeline

BLU-63A/B submunition Key Events

  1. Development begins

    GAO said development of the BLU-63/B bomblet began late in 1966 after an Avco proposal to replace the BLU-26/B.

    Sources: Review of BLU-63/B Bomblet Program

  2. First-source contract awarded

    GAO recorded Ajax Hardware Manufacturing's 3-year contract for 42 million BLU-63/B bomblets at $0.28775 each.

    Sources: Review of BLU-63/B Bomblet Program

  3. Second source added

    GAO recorded a Hoffman Electronics letter contract for 23,750,600 bomblets at $0.35 each.

    Sources: Review of BLU-63/B Bomblet Program

  4. Remnants documented in Yemen

    OSMP documented BLU-63A/B remnant material in a CBU-58A/B cluster-bomb strike site in Hajjah governorate.

    Sources: OSMP 1545 CBU-58A/B Yemen Remnant

  5. Coalition cluster-bomb evidence in Sanaa

    Human Rights Watch documented CBU-58 cluster bombs with BLU-63 submunitions in Sanaa.

    Sources: Yemen: Coalition Drops Cluster Bombs in Capital, Technical Briefing Note: Cluster Munition Use in Yemen

Media

BLU-63A/B submunition Images

BLU-63A/B submunition, Air-dropped high-explosive fragmentation bomblet, Munitions - view 1
Source: BLU 63B bomblet, air-dropped
Related Weapon Systems
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Sources

OSMP 1545 CBU-58A/B Yemen RemnantPublisher: Open Source Munitions Portal | Note: Supports 2014 Yemen Civil War direct use: BLU-63A/B submunitions were used by Saudi/UAE-led coalition forces through CBU-58A/B cluster bombs documented in Hajjah governorate in 2015. | Accessed: 2026-06-20Yemen: Coalition Drops Cluster Bombs in CapitalPublisher: Human Rights Watch | Note: Supports 2014 Yemen Civil War direct use: BLU-63 submunitions were used by Saudi-led coalition forces in CBU-58 cluster bombs documented in Sanaa on January 6, 2016, with markings tied to Milan Army Ammunition Plant. | Accessed: 2026-06-20Technical Briefing Note: Cluster Munition Use in YemenPublisher: Human Rights Watch | Note: Supports 2014 Yemen Civil War direct use: CBU-58 bombs with BLU-63 submunitions were used by Saudi-led coalition forces in Sanaa in January 2016. | Accessed: 2026-06-20BLU 63B bomblet, air-droppedPublisher: Imperial War Museums | Note: Supports specifications, background, and image provenance under the IWM Non-Commercial Licence for the BLU-63B bomblet images. | Accessed: 2026-06-20Review of BLU-63/B Bomblet ProgramPublisher: U.S. Government Accountability Office | Note: Supports late-1966 development, production-program background, BLU-63/B technical context, and the reported $0.28775 and $0.35 unit prices in the 1970-1971 procurement history. | Accessed: 2026-06-20Bomb, HE Frag, BLU-63/BPublisher: Bulletpicker | Note: Supports BLU-63/B and BLU-63A/B variant background, impact-fired fuzing, training variant context, and visual marking notes. | Accessed: 2026-06-20F-16 Non-Nuclear Weapons Delivery Manual ExtractsPublisher: Archive.org | Note: Supports the CBU-58A/B load of 650 BLU-63A/B bomblets, the SUU-30H/B carrier relationship, and the titanium-pellet incendiary difference between BLU-63/B and BLU-63A/B. | Accessed: 2026-06-27