The U.S. Army has a new version of the Hellfire II air-to-ground missiles, that has several new features. The most recent capability is an electronics package (a circuit board and internal sensors) that monitors and reports the status of missile components. This Captive Carry Health Monitoring package constantly tracks the status of the missile, and the environment (heat, vibration and humidity). Maintenance personnel can jack into the missile and get a report at any time, making it easier to keep missiles fit for action. Older versions of the missile required this information to be logged manually, and much more effort to insure that the missile was ready for combat.
Another new feature enables the missile to go after targets directly below, or behind, the aircraft firing it. This solves a particular problem with UAVs, because the vidcam on board can spot targets directly below, or even behind, the aircraft, while the Hellfire was designed to only go after targets in front of it. The new Hellfire accomplished all this with a multifunction guidance system. The new guidance system is also more accurate against moving targets.
The AGM-114 (Hellfire II) missiles use either an armor-piercing or blast/fragmentation (for use against non-armored targets and bunkers) warhead. The ones fired from UAVs usually have the blast warhead. The Hellfire II weighs 106 pounds, carries a 20 pound warhead and has a range of 8,000 meters. In addition to UAVs, the missile is most commonly used by the AH-64 helicopter gunship. An AH-64 can carry up to sixteen Hellfires at once. Predator, Reaper and Sky Warrior UAVs also use the Hellfire. The missile is popular for use in urban areas, because the small warhead (less than 2 kg/4.4 pounds of explosives) reduces civilian casualties. The missile is accurate enough to be sent through a window (OK, you have to be really good, and lucky, to do this) because of its laser guidance. Hellfire is the most frequently used missile during the war on terror.