Combat operations begin in Operation Allied Force, the NATO air campaign against Yugoslavia. US aircraft fly about two-thirds of the 45,000 sorties, pressuring Serb leader Slobodan Milosevic to withdraw his forces from Kosovo.
Small satellites meant to improve the way the U.S. measures Earth’s magnetic field—an option to expand the military’s position, navigation, and timing enterprise—launched March 30 from Vandenberg Space Force Base, Calif.
