"Significant changes" in the weapons mix of the U.S. Navy are needed during the next 25 to 35 years. So reports a National Research Council panel on naval weapons. The study calls for increased use of smart weapons, stealth, and electronic warfare. Needed is a family of low-cost, high-volume, long-range precision ballistic weapons for surface-to-surface operations. Also recommended: a new air-to-air weapon, mines operated by networked sensor systems, and an array of non-lethal weapons. More emphasis should be put, the panel says, on undersea weapons optimized for offensive and defensive operations in coastal regions. In the future, it adds, a greater percentage of ordnance will ride on standoff air-to-surface weapons. These weapons must receive target information from off-board sensors, as well as have autonomous capabilities to continue their attack in the face of countermeasures.