It was impossible not to feel chills or tear up at the Delaware Military Academy’s Patriot Day ceremony of remembrance for 9/11. During Monday’s event, students took turns role-playing as the aircraft announcers on Sept. 11, 2001, making announcements for takeoffs, weather, destination and arrival times. “Welcome aboard United Airlines Flight 175,” one student said. “It is 8:14 a.m. and …