The futuristic Heckler & Koch HK XM25 IAWS - Individual Airburst Weapon System - (now as the CDTE = Counter Defilade Tarfet Engagement) is a semi-automatic, multiple-shot, shoulder-fired 25mm grenade launcher categorized as an "airburst weapon" system designed to neutralize out-of-view targets. The term airburst is derived from the launcher's use of fuze delayed detonated munitions which allow for a higher kill probability. Initial prototypes were handed over to the United States Army for field-testing in April of 2005. By the middle of 2009, field tests in combat zones from Iraq to Afghanistan were taking place. The project - barring any program setbacks - should see wide scale fielding in 2012.
The general basis of the XM25 is in its rangefinding and delayed munition detonation capabilities. The operator activates the laser rangefinder and determines the distance to a target or target area. Once determined by the rangefinder, the operator then has the freedom to "fine-tune" the detonation delay of the projectile before firing by adding to - or subtracting - distance. The chambered grenade is "imprinted" with the calculated distance via a microchip fitted into every 25mm projectile. The operator pulls the trigger and propels the grenade onto its flight path. The grenade then automatically follows through by calculating how many rotations have occurred since it was launched from the rifled barrel. Once the pre-set range is reached, the grenade detonates itself at or in the area of the target. In essence, it is a "smart" weapon - though still requiring user input, it handles a great deal of the actual work post-fire. A first-kill probability is noted to be very high at least against target mannequins.
The XM25 is designed in a "bullpup" configuration, meaning that the magazine and applicable feed system is mounted to the rear of the pistol grip, trigger group and receiver. This provides for a stable hold when up against the operators shoulder as it necessitates a larger and heavier stock. The specialized optical system -the Target Acquisition Fire Control System - is fitted above the receiver. The forward portion of the weapon body is contoured to fit nicely in the free hand of the operator to further assist in bracing the weapon. The pistol grip features an integrated guard running forward of the trigger to the base of the pistol grip. Overall weight (6.3 kilograms) is said to be comparable to an M16 assault rifle with the 40mm grenade launcher attachment. Range is listed at 500 meters for point targets and up to 1,000 meters for ranged area targets. In some ways, the XM25 is similar in appearance to another - albeit ill-fated- Heckler & Koch / Alliant Techsystems joint development, the XM29 OICW, the XM25 actually born from this aborted effort.
The XM25 makes use of a low-velocity 25x40mm grenade munition. The launcher can fire this caliber of grenade in varying forms including a two-warhead high-explosive round (HEAB - High-Explosive Air Bursting), a flechette-laden (arrow) round and a thermobaric round (useful in confined spaces such as caves). Additionally, there will be standard training rounds as well as non-lethal rounds. The weapon fires from a 4-round oversized magazine fitted to the rear of the weapon.
The heart and soul of the XM25 is its Target Acquisition Fire Control System (TAFCS). This complex piece of equipment (developed by L-3 Communications Brashear) allows the XM25 operator to engage and fire on targets in day or night (the latter via thermal imaging), in adverse weather conditions and against targets in defilade - that is, hidden from view in a ditch or ravine. Similarly, the weapon will give the US soldier the capability to engage targets inside of buildings, firing from windows. The soldier need only his weapon to calculate the distance past the window frame, fire the XM25 and have the grenade detonate once it is inside the room, hopefully defeating the enemies within - all this with little damage to the building's major internal substructure. The laser rangefinder is activated through a button found along the front side of the XM25's trigger guard. The trigger guard also has the controls to fine-tune the range, adding or subtracting meters to the chambered grenade "on-the-fly". Aiming is via an adjusted crosshair aim point in the optical lens where the recorded target distance is also displayed. The fire control system evaluates the current air temperature and pressure and takes into account the inherent ballistics of the 25mm round for the presented range.
The US Army is intending to purchase some 12,500 M25 systems beginning in 2012 in an effort to field at least one unit with each of its infantry squads as well as for its Special Forces detachments. Primary development of the weapon has been handled by Heckler & Koch GmbH of Germany and Alliant Techsystems of Minnesota, USA.
The first successful test fire of the XM25 by a US soldier occurred at Aberdeen Test Center in Maryland on August 11th, 2009. Testing has shown results on practice targets to be up to 300% greater than that of current squad level weapons tasked to do the same job. Training on the XM25 has also been noted as swift with new XM25 operators being made ready to fire the weapon within five minutes time.
February of 2013 saw the XM25 removed from Afghanistan operations due to a live-fire misfire incident. In June of that year, the program suffered a funding cut, removing 1,400 XM25 weapons from the 2014 procurement budget.