American 18-inch torpedo
There have been a number of 18-inch torpedoes in service with the United States. These have been used on ships and submarines of the US Navy. American "18-inch" torpedoes were actually in diameter, beginning with the "Fiume" Whitehead torpedo of 1890.
Ship classes that carried 18-inch torpedoes include:
- Aylwin-class destroyers
- B-class through some R-class submarines
- Bainbridge-class destroyers
- Cassin-class destroyers
- Cincinnati-class cruisers
- Columbia-class cruisers
- Illinois-class battleships
- Indiana-class battleships
- Kearsarge-class battleships
- Maine-class battleships
- Montgomery-class cruisers
- Paulding-class destroyers
- Pennsylvania-class cruisers
- Plunger-class submarines
- Smith-class destroyers
- Truxtun-class destroyers
| Name | Country | In service date | Platform / target | Dimensions | Warhead | Propulsion | Performance |
| "Fiume" Whitehead torpedo |  USconvert|17.7|in|cm|abbr=onconvert|140|in|cm|abbr=onconvert|845|lb|kg|abbr=onconvert|54|kg|lb|abbr=onconvert|26.5|kn|km/h|abbr=onconvert|730|m|yd|abbr=on|order=flip |