The B-2 bomber is undergoing final tests of new bomb racks that enable it to carry, and release at precise times, up to 80 500 pound JDAM GPS guided bombs. Currently, the B-2 can carry 16 2,000 pound JDAM bombs. But this large bomb is generally not used in populated areas because of the danger of civilian casualties. JDAM is accurate enough that one 500 pound bomb can destroy a target that would have required several older "dumb" 2,000 pound bombs, or dozens of dumb 500 pound bombs. With the smaller JDAM bombs, the B-2 can hit a lot more targets per sortie. The B-2 requires expensive and time consuming maintenance between sorties, so the more bombs per mission the better. The F-15E has also been equipped to drop JDAM. Previously only the F-16 and heavy bombers could drop JDAM. To use JDAM, an aircraft must be equipped with GPS and wired so that the pilot can program the JDAM with the GPS coordinates of the target.