In olden days it took as much as 20 minutes to load and fire a gun, so that a ship that fired her guns in salute did so as a friendly gesture, making herself powerless for the duration of the salute. The gun salutes prescribed by Navy Regulations are fired only by ships and stations designated by the Secretary of the Navy. Salutes are fired at intervals of 5 seconds, and always in odd numbers.
A national salute of 21 guns is fired:
- On Washington's Birthday
- On Memorial Day
- On Independence Day
- To honor the President of the United States
- To honor heads of foreign states.
Salutes for naval officers are:
- Admiral: 17 guns
- Vice Admiral: 15 guns
- Rear Admiral: 13 guns
- Commodore: 11 guns