The U.S. aviation regulator proposed rules for commercial drone flights that would lift some restrictions but would still bar activities such as the delivery of packages and inspection of pipelines that have been eyed by companies as a potentially breakthrough use of the technology. Reuters reports that the long-awaited draft rules from the Federal Aviation Administration would require unmanned aircraft pilots to obtain special pilot certificates, stay away from bystanders and fly only during the day. They limit flying speed to 100 miles per hour (160 kph) and the altitude to 500 feet above ground level. Read more at USAgNet…