When I was in the Navy, one of my guilty pleasures was saluting a Colonel and calling them Cap'n. I never had one stop to correct me, but some of the faces I got were priceless! For those who don't know the ranks, a Captain in any service other than the Navy and Coast Guard is 3 grades lower than a Colonel, which is the same in rank as a Navy Captain who wears the same eagle insignia.

Fair wind and following seas, Cap'n!