^Rank codes are not provided for enlisted Naval personnel in Halo: Official Spartan Field Manual. While it is likely they use the same "E-1, E-2" etc. system as other rank codes, they are omitted from this table as to only display confirmed information.
^The "CR" abbreviation is also used for Crewman Recruit in the Halo: Official Spartan Field Manual. In real life Crewman uses the abbreviation "CN", leading to it likely a typo for Crewman to use this. CR is however used here due to it appearing in one source.
^Although Master Chief Petty Officer is the official rank held by many naval servicemen, they are typically referred to as "Top Chief" by crew out of respect for John-117, more commonly known as "The Master Chief".