sign,  "Bat 21", he used in Vietnam when he was shot down in 1972 while  jamming enemy radar, and parachuted behind enemy lines. When on the  ground Col Hambleton found himself in the midst of an invasion force  of over 30,000 North Vietnamese troops. While evading capture for  eleven days he used his survival radio to call in air strikes  against the invasion force. Rescue crews gave him coded instructions  for where to go to be rescued based on golf course that he had  played at different air force bases. Hambletons harrowing ordeal  was recounted in the book Bat 21 (1980), which was made into a movie  of the same name in 1988. He died from cancer on September 19 2004  at age 85.