What is a Senior Officer Present Afloat?


Senior Officer Present Afloat, usually referred to as SOPA, is a US Navy term to indicate the US Navy officer, with the highest ranking by rank, or number in rank, present in a harbour occupied by more than one US Navy vessel. That officer is essentially commander of all US Navy operations afloat in the harbour and is responsible to civilian authorities for the action of the ships and the behaviour of crews under their command.

SOPA is a useful administrative function in foreign ports visited by US Navy vessels. However, SOPA may also be established in continental US ports.

Examples of SOPA Assignment

  • A US Navy minesweeper enters the harbour of Sasebo, Japan, where there are a number of US Navy destroyers at anchor. The captain of the minesweeper is a lieutenant commander who, informed by message beforehand as to who is SOPA, must report to the higher-ranking SOPA, a commander, located on one of the destroyers. The SOPA will assign the minesweeper instructions as to where to anchor or dock, and instruct the minesweeper on guard duty, mail runs, boat runs, radio watch, signal light watch, liberty procedures, shore patrol assignments, and other assigned shared duties.
  • A cruiser with a higher-ranking Navy officer, such as a captain, enters the same port. The commanding officer of the cruiser immediately becomes SOPA and issues its own instructions and assignments.
  • During periods of cooperation between Allied navies, such as during World War II or the Korean War, the Allied officer with the highest ranking assumes the position of SOPA. In such cases, for example, the captain of a Royal Navy destroyer may be SOPA and have responsibility for smaller US Navy vessels under their jurisdiction.


SOP(A) is the term used for “Senior Officer Present (Ashore).”

This page is based on the copyrighted Wikipedia article < https://en.wikipedia.org/wiki/Senior_Officer_Present_Afloat >; it is used under the Creative Commons Attribution-ShareAlike 3.0 Unported License (CC-BY-SA). You may redistribute it, verbatim or modified, providing that you comply with the terms of the CC-BY-SA.


This site uses Akismet to reduce spam. Learn how your comment data is processed.