The US Air Force could soon have a new air-delivered tool in its arsenal for destroying chemical and biological weapons – a Hammer, fittingly, or Heated And Mobile Munitions Employing Rockets.

A $7.2 million contract recently awarded to General Dynamics Ordnance and Tactical Systems Aerospace furthers the development of a new munitions concept, which involves littering an underground bunker or weapons storage facility with hundreds of 2.4kg (5.5lb) rocket-propelled fireballs designed to incinerate chemical and biological agents at temperatures in excess 538°C (1,000°F).

The “kinetic fireball incendiaries” would be delivered inside a 907kg (2,000lb) BLU-109B bunker bomb – which has enough punching power to penetrate 1.8m (6ft) of reinforced concrete.

A spokeswoman for the air force’s armaments directorate at Eglin AFB in Florida tells Flightglobal that over the next nine months, General Dynamics will demonstrate three basic subsystem functions – ejection, ignition and dispersal. Additional contract options are available to fund static and sled testing of the complete HAMMER weapon system.

There are currently no flight tests planned, since that depends on the success of the sled tests.

“The full HAMMER system has not been tested or demonstrated,” the armaments directorate says. “The purpose of the program is to demonstrate the viability of this concept.”

The primary customer for the weapon is the US Defense Threat Reduction Agency (DTRA), which since its formation in 1998 has been searching for new and creative ways to demolish weapons of mass destruction, be them nuclear, chemical or biological.

Among its more noted creations is the 1.4-ton (30,000lb) Massive Ordnance Penetrator, which is a high-explosive bomb carried aboard the Northrop Grumman B-2.

Another odd device is the 453kg (1000lb) CBU-107 Passive Attack Weapon, which sprays thousands of tiny tungsten darts on impact to rupture storage tanks and was used during the US invasion of Iraq.

What’s special about HAMMER is that is doesn’t explode or overpressure the bunker as to avoid inadvertently dispersing the harmful chemical or biological agents it is trying to destroy.

The concept was patented by Californian technology company Exquadrum in 2006, and has been in development with the Pentagon since 2010 as a DTRA “small business innovative research project”.

The air force and General Dynamics both say Exquadrum remains a key partner and subcontractor on the programme. It is responsible for producing the kinetic fireball incendiaries payloads.

The BLU-109B, paired with Raytheon’s Paveway III laser guidance system, is a standard US penetrating weapon and is integrated with most of its fighter and bomber aircraft.