"Three minutes before United Airlines Flight 175 crashed into the South Tower of the World Trade Center on 9/11, passenger Brian Sweeney used an Airfone to leave a heartbreaking final voicemail message to his wife Julie. At the time, she was in the middle of teaching a high school class, so she missed his call. Though Julie was soon pulled away from her students to learn that her husband had died in the attacks, she didn't realize that he had left her a message until she got home. ⁠"