colonel (JASDF, JGSDF); captain (JMSDF)
Military rank used in the Japan Self-Defense Forces. Equivalent to colonel in the Air and Ground Self-Defense Forces, and captain in the Maritime Self-Defense Force.
He was promoted to colonel in the JGSDF.
Captains in the JMSDF often serve as ship commanders.
Numerical variant sometimes seen in official documents or tables.
The rank name 一佐 is a modern Self-Defense Force term, combining 一 (one) and 佐 (assistant/field officer), following the SDF's unique rank naming system.