The U.S. Army is converting thousands of its older AGM-114K Hellfire missiles to the new AGM-114R standard. The AGM-114R completed its final testing three years ago. Hellfires are the most frequently used American missiles these days. The AGM-114R (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 48.2 kg (106 pounds), carries a 9 kg (20 pound) warhead, and has a range of 8,000 meters.

Hellfire II has several new features. For example, it has 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.

In addition to UAVs, the Hellfire 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 are the best known users of Hellfire. The missile is popular for use in urban areas because the small warhead (containing only about a kilogram/2.2 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. The AGM-114R has also been test fired from a ground mount (a simple tripod device).