The BL755 submunition dispensing cluster bomb is manufactured by Hunting Engineering of Ampthill, Bedford, UK and has been in service with the RAF for over 27 years. Although due to be replaced in the anti-armour role by Brimstone, it still remains a formidable area attack and denial weapon.

The 272kg (600lb) BL-755 comprises a finned casing containing 147 High Explosive Anti Tank (HEAT) bomblets packed in seven sections of 21 rounds each. Following separation from the aircraft the outer casing covers are jettisoned by a gas ejector at one of four pre-set times. The bomblets are then ejected sideways as much as 18m (60ft) at pre-set intervals. Each of the ejected submunitions are then orientated by the deployment of a parachute while a spring mounted base plate is activated to give the correct stand-off for the shaped charge. The warhead is designed to explode on impact, being triggered by a piezoelectric fuze which is located under the base plate. Upon detonation the shaped charge produces a jet of high velocity, high temperature plasma which can punch through up to 250mm armour. In addition the release of 2000 pieces of shrapnel produces a secondary anti-personnel effect.

BL755 submunition in Bosnia © CPT Chris Miller XO

Changing operational requirements became evident after the 1991 Gulf War. It was found that the required low level delivery profile used for delivery of the BL-755 put the aircraft and their crew through unnecessary risk from AAA, ground-fire and MANPADS. Therefore there was an immediate need for some kind modification to allow delivery from medium and high altitudes. However there remained a requirement for a low level capable system where air superiority had not been gained thus risking the aircraft at higher altitudes.

Hunting responded to this request by producing a radar proximity sensor kit to retrofit to existing BL-755's (which are now classified as RBL-755) enabling delivery of the weapon from any altitude. The kit is mounted to the rear of the casing where it can detect the bombs height from the ground. This system allows release of the submunitions at a pre-defined altitude without any further aircraft involvement. Therefore the aircraft is free to fly at the safest weapon delivery level in all tactical situations.

A further variant of the BL-755 is the HADES. Essentially it is the outer-casing of the BL-755 but instead of 147 HEAT charges it contains 49 2.5kg HB.876 area denial submunitions as used in the JP.233 anti-airfield weapon. The physical dimensions of the system are the same as the standard BL-755 but it is slightly lighter at 259kg (571 lbs). Since the HB.876 is classed as an anti-personnel mine it is now unlikely that HADES remains an active weapon in the UK arsenal since it has signed the Anti-Land Mine Treaty.

Over 52,000 BL-755 weapons have now been produced for use by 16 countries (not including the UK) and it is deployed on 22 different aircraft. The radar upgrade is also available, on a case by case basis to all the current users.

* : Note that all ranges quoted are based on mean figures from various data sources. Actual achievable range will depend on a great number of factors and may be no where near those quoted.