October 28, 2010: Recently, the U.S. successfully tested the new JMEW (Joint Multi-Effects Warhead System) warhead for its Tomahawk Block IV cruise missile. The new, 450 kg (1,000 pound) warhead is designed mainly for penetrating underground bunkers, but it will also provide excellent blast effect for less robust targets. Exact penetration was not revealed. JMEW uses laser terminal guidance, enabling it to hit within a few meters (ten feet) of its aiming point. JMEW can also hit moving targets. The Block IV Tomahawk can be reprogrammed in flight to hit another target and carries a vidcam to allow a missile to check on prospective targets.

The RGM-109E Block IV Surface Ship Vertical Launched Tomahawk Land Attack Missile weighs 1.2 ton, is six meters (18 feet) long, has a range of 1,600 kilometers, getting there at a speed of 600-900 kilometers an hour, flying at an altitude of 17-32 meters (50-100 feet) and propelled by a jet engine generating only 600 pounds of thrust. Accuracy is on a par with JDAM (10 meters/ 31 feet).