The revolutionary aspect of this new weapon is its ability to engage enemy targets beyond the reach of the M16, particularly those in defilade, in trenches, behind trees, inside shelters and on rooftops. OICW combines the lethality of 20mm high-explosive (HE) air-bursting ammunition and 5.56mm NATO kinetic-energy (KE) ammunition with an advanced fire-control subsystem. The air-bursting ammunition contains a settable smart fuse that ensures warhead function precisely over the target. In 300 metre engagements, the OICW is projected to increase the probability of enemy incapacitation by more than 500 per cent, substantially increasing soldier survivability. In addition it doubles stand-off range, reduces a soldier's load and substantially increases combat versatility.

Proof-of-principle
In April 1998 the joint service small arms programme (JSSAP) office at the US army armament research, development and engineering centre (TACOM-ARDEC) awarded an $8.5m contract modification for the OICW system to Alliant Techsystems, a defence and aerospace manufacturer headquartered in Hopkins, Minnesota. The contract modification provides for multiple systems to be delivered for advanced technology demonstration (ATD) assessment. Alliant is responsible for total weapon-system definition, integration and testing and 20mm HE ammunition. Alliant's international team includes Contraves Brashear Systems, Inc. (fire- control system); Heckler and Koch GmbH and HK Inc. (weapon design and US manufacture); Dynamit Nobel AG, (5.56mm ammunition product improvement and HE propulsion system); and Octec (target tracker).

Proof-of-principle ATD system testing in early 1998 demonstrated that OICW can deliver precisely 20mm ammunition with an air-burst fuse and fragmenting warhead to targets at ranges up to 1,000 metres. The round is designed to explode in the air precisely over the target. Lethality is expected to be five times more effective at more than twice the range than that of the M16/M203 40mm grenade system. Laser ranging achieves the accuracy needed to ensure precise delivery of the ammunition to the target. Recoil was demonstrated to be only slightly more than that of the M16. This provides for repeatable firing of the 20mm system without damage to the weapon or injury to the soldier's shoulder.

The fielded OICW is required to weigh less than 14 pounds, including 30 rounds of 5.56mm KE ammunition and at least eight rounds of 20mm HE ammunition. By comparison add-ons to the M203 system to provide limited fire-control capability bring its weight to slightly less than 20 pounds.

The OICW's added capability increases the dismounted infantryman's effectiveness dramatically. "The M16 is a very accurate weapon. However, when it is placed in the hands of an individual under combat-stress conditions, its performance is reduced dramatically," says Steve Mango, JSSAP OICW advanced technology demonstration programme manager. "The M16 family of weapons also has no capability to defeat targets in defilade and the M203 grenade launcher has a maximum effective range of only 250-300 metres. The OICW will improve effectiveness at all ranges up to 1,000 metres and be capable of defeating exposed targets and those in defilade."

Of course, technical specifications don't tell the whole story. In one simulated combat environment, an OICW prototype showed the weapon's true potential at extended range. When the simulation results were tallied, the virtual units firing M16/M203s suffered many casualties. Those firing the OICWs showed dramatically reduced casualties because of the weapon system's standoff engagement capability and its ability to defeat targets in defilade. In real combat soldier-survivability is the only statistic that counts.

"The OICW effectively defeats various targets at extended ranges and increases the survivability of the operator significantly, and so will save the lives of US servicemen and women that may have to use it in the future," said Mango. "If I were going into combat I would want an OICW because it increases the probability of returning home to my family."

Weapon system eliminates guesswork