The Army plans to seek certification for its ground-based, sense-and-avoid system for unmanned aircraft following a successful demonstration this month, according to an official leading the effort for the Defense Department. The demonstration is a major step toward enabling the Pentagon to integrate drones into the national airspace. During the weeks of June 4 and June 18, the Army validated the technology and capabilities of the system by flying live and simulated drones in a series of vignettes to see...