Two Delta passenger planes flew so close to one another that both of their collision warning systems were triggered. Delta Flight 1568 aborted a landing at Hartsfield-Jackson Atlanta International Airport as it flew in from Pittsburgh on Monday evening. Delta flight 2472 was taking off from a parallel runway as the tower directed the 8-year-old Airbus A321 to climb 4,000 feet on a right turn. “Delta 1568, going around,” the pilot of the landing plane repeated before being told also to climb 4,000 feet on a right turn, setting off both planes’ anti-collision alarms. In a statement, Delta said, “During the go-around, the flight crew maneuvered in accordance with established procedures while maintaining safe operations.”