 Collier was assigned to the Great Lakes Naval Training Station outside of Chicago , where he was a survival swimming instructor . It was in the Navy that Collier first had trouble with his hearing , a problem that dogged him later in life . He was once called to report to his ship over a loudspeaker but did not hear it . Doctors thought his hearing may have been damaged by teaching swimming in a tidal pool or from practicing on the shooting range . " It never became an issue until the Navy , when they figured he had less than 40 % of a normal person 's hearing , " his daughter Kay Collier @-@ <unk> said in 1997 . To compensate for his hearing loss , Collier became an expert lip @-@ reader . 
