No, Master Chief is in the fictional United Nations Space Command, or UNSC. That's why UNSC is plastered all over everything. Master Chief (or Spartan 117, or more simply "John") isn't even from Earth. There's several Halo books out there that can help you get the full story.
1967
A former boss of mine was career navy, and held the rank of Master Chief Petty Officer. He told me his pay scale was E-9.
Terry D. Scott.
Master Chief Petty Officer of the Navy Rick D. West .
Dear Chief ______: If he is a Senior Chief PO or Master Chief PO, then it would be "Dear Senior Chief _____ or Dear Master Chief ______."
Master Chief Johnson
There are currently 16 Force Master Chief Petty Officers in the Navy. Below this answer is a link for further information on the subject.
Gunners Mate Master Chief
AVCM designates a Master Chief (E-9) Avionics Technician
Fran Walker is the wife of the now retired, third Master Chief Petty Officer of the Navy, Robert (Bob) Walker.
There is no kind of about it. Both the US Navy and Coast Guard use the Rank Master Chief Petty Officer for the highest enlisted rank. Only Warrant and Commissioned officers rank above Master Chiefs.
Master Chief Petty Officer of the Navy