Red, a 12-year-old Labrador who is retired as an active search dog, sits in her yard in Annapolis, Maryland, August 18, 2011. Not long after American Airlines flight 77 crashed into the Pentagon on September 11, 2001, Red was at work. [Photo/Agencies]

Red, a 12-year-old Labrador who is retired as an active search dog, waits in her crate after completing a training exercise in Pumphrey, Maryland, August 18, 2011. Not long after American Airlines flight 77 crashed into the Pentagon on September 11, 2001, Red was at work.[Photo/Agencies]