XM25 Individual Semi-Automatic Airburst System (ISAAS)
Counter Defilade Target Engagement (CDTE) System
Objective Individual Combat Weapon (OICW) Increment 2

The XM25 Individual Semi-Automatic Airburst System (ISAAS), also known as the Counter Defilade Target Engagement (CDTE) System, and perviously referred to as the Air-Burst Assault Weapon or Air-Burst Weapons System, is semi-automatic firing 25mm ammunition, including a high-explosive air-bursting (HEAB) round. The weapon weights 12 to 12.5 pounds, is 29.5 inches long, and has a magazine capacity of 4 rounds. Each weapon is equipped with a fully integrated day/night full solution target acquisition/fire control optic and is made of lightweight material composites.

The XM25 Air Burst Assault Weapon was developed from the the air-burst portion of Objective Individual Combat Weapon (OICW), termed OICW Increment 2. The complete system, the XM29 Integrated Air Burst Weapon, was to be OICW Increment 3. The XM25 dramatically was designed to increase soldier survivability, standoff, and versatility. The air-burst weapon provided the soldier with a 300-500 percent increase in hit probability to defeat point, area and defilade targets out to approximately 500 meters. The XM25 weapon included revolutionary HEAB munitions and an integrated, multifunctional, all environment, full-solution target acquisition and fire control system. This system integrated thermal, powered direct-view optics, laser rangefinder, compass, fuze setter, ballistic processor, and internal display. The XM25 25mm Air-Burst Weapons System provided the infantry soldier with a decisive overmatch capability in a next-generation weapon system that would dramatically increase lethality, range and capability through the use of a family of munitions consisting of thermobaric, high explosive air bursting (HEAB) ammunition.

The XM25's HEAB 25mm round was capable of defeating an enemy behind a wall, inside a building or in a foxhole. Expected to weighing in at less than 12 pounds, the XM25 incorporated a complex target acquisition fire control system. As the round flies downrange to the target, it precisely measured the barometric pressure, temperature and velocity of the projectile to a computer chip in the round so that it detonates at exactly the right moment to deliver maximum effectiveness. The XM25 was determined to be 5 times more lethal at the M203 maximum range and provided lethality well beyond the M203's maximum ability, giving Soldiers a 300-500 percent increase in hit probability, according to weapon specifications.

The XM25 had a 300-meter range point target and 500-meter range area target capable of defeating defilade (hidden) targets. The XM25 has a 500-meter range against point targets and 500-700-meter range against area targets, and was capable of defeating defilade (hidden) targets. The system was ideal for urban combat, with the XM25 putting precision firepower in the hands of the soldier, allowing him or her to eliminate threats without causing significant collateral damage.

Spiral development of the XM29, began in 2004, was expected to accelerate fielding of the XM25 subsystem in advance of the dual barrel system. This coincided with a change in ammunition for the air-burst componet of the XM29, and subsequently a change for the XM25. Originally, a 20mm round was to be used. This was changed in 2004 to a 25mm round. Development of the XM25 would maximize commonality of parts and share the same logistics and supportability resources of the XM29. This system supported the Current to Future transition path of the Transformation Campaign Plan.

Alliant Techsystems Integrated Defense of Plymouth, Minnesota; Brashear L3 of Pittsburgh, Pennsylvania, and Heckler and Koch, Gmbh of Oberdorf, Germany worked in conjunction with the Project Manager Soldier Weapons to develop the XM25. The XM25 Air Burst Assault Weapon was expected to reach Milestone B in FY05. The System Development and Demonstration (SDD) phase was expected to complete development of the XM25 weapon system and verify training solution for the Milestone C approval in FY08.

By November 2010, the US Army planned on purchasing more than 12,500 XM25 systems starting in 2012. As of May 2010, the XM25 program was fully funded and in testing and development with limited production expected in 2012. Special operations forces were expected to be the first units to use the XM25. Requests from Afghanistan for the weapon, however, saw the deployment of the first systems to elements of the 101st Airborne Division in Afghanistan in late 2010.