USS Nautilus
USS Nautilus is a nuclear-powered submarine operated by United States Navy, powered by S2W of about 10 MWt. Retired.
The first nuclear-powered vessel of any kind, and the origin of the pressurised water reactor as a product. Every PWR operating today, 743 of them by fuel family, descends from a programme to make a submarine that never had to surface. The civil industry inherited naval engineering, not the other way round.
| Reactor | S2W |
|---|---|
| Reactors per vessel | 1 |
| Thermal output | 10MWt |
| Fuel enrichment | 93% U-235HEU |
| Refuelling | Core life of about 900 hours at full power |
| Category | submarine |
|---|---|
| Role | SSN |
| Operator | United States Navy |
| Country | United States |
| Vessels in class | 1 |
| In service from | 1955 |
| Status | Retired |
Other submarines
| Class | Enrichment | Status |
|---|---|---|
| AUKUS submarines | HEU | Planned |
| Akula class | - | Operating |
| Alfa class | HEU | Retired |
| Arihant class | HEU | Operating |
| Astute class | HEU | Operating |
| Borei class | HALEU | Operating |
| Columbia class | HEU | Under construction |
| Dreadnought class | HEU | Under construction |
| Han class (Type 091) | - | Operating |
| Le Triomphant class | LEU | Operating |
| Los Angeles class | HEU | Operating |
| Ohio class | HEU | Operating |
| Oscar II class | - | Operating |
| Seawolf class | HEU | Operating |
| Suffren class (Barracuda) | LEU | Operating |
| Type 093 and 094 (Shang and Jin) | LEU | Operating |
| Typhoon class | - | Retired |
| Vanguard class | - | Operating |
| Virginia class | HEU | Operating |
| Xia class (Type 092) | - | Retired |
| Yasen class | HALEU | Operating |
USS Nautilus in context
It is one of 22 submarine programs on record, 15 of them operating and 4 retired, and one of 11 naval reactor programs from the same country.
Each of its reactors is rated about 10 MWt; across the 19 submarine programs with a stated rating the median is 165 MWt, and this one ranks 19th.
Its fuel is recorded as HEU, the same as 10 of the other 15 submarine programs with a stated enrichment class.
It entered service in 1955, 71 years ago; the submarine programs on record entered service between 1955 and 2020, and this one is the earliest of 17.
| Measure | USS Nautilus | Median of submarine programs | Standing |
|---|---|---|---|
| Thermal power per reactor (MWt) | 10 | 165 | 19 of 19 |
| Entered service | 1955 | 1997 | 1 of 17 (earliest first) |
Worked out from the entries on this site only, so a figure compares USS Nautilus with what is recorded here, not with everything that exists. An entry with no value for a measure is left out of that measure's ranking and median.
Sources
- World Nuclear Association, Nuclear-Powered Ships · retrieved 2026-09-07
How these sources are used, including the corrections applied on top of them and what is deliberately left blank · download the underlying data