NationStates Jolt Archive

I am just wondering what is the smallest possible submarine that could feasibly use nuclear power. (smallest meaning displacement and length) I don't just mean to slap a nuclear reactor into a sub and say i did it. But, that it is worth it to put a nuclear reactor in a small sub.

I am just wondering what is the smallest possible submarine that could feasibly use nuclear power. (smallest meaning displacement and length) I don't just mean to slap a nuclear reactor into a sub and say i did it. But, that it is worth it to put a nuclear reactor in a small sub.


Look up Admiral Rickover's NR-1.

For small subs IMO better go with diesel they make less sound then a nuclear powered sub of the same size.However, you can't take it in the open blue sea.What I mean is that this advantage is neglected if you want to cross oceans.A diesel need to recharge its batteries and then must use its diesel engine which makes an awful lot of noise.

as size decreases, efficency decreases. the smaller the hull, the more room percentage wise to make a efficent, effective, fast sub. things scale down and become less effective with size. just look at airplanes. a cessena 172 private plane the size of a goose wouldnt fly. a little over a high 90% rate of air would woosh by uselessly and it's wing wouldnt create enought lift to fly. not to mention the fuel would be used up in about 3 hours for the tiny, inefficent engine to generate enough power to power the propeller.

id say a school bus (the long ones 60 feet long) would be a bare minimum size for an unmanned sub.
120 feet for a manned sub i think?

I thank you for your answers, and they have been most helpful.

The smallest nuclear powered submarines in service today:

Amethyste class (France)
Displacement: 2,670 tons submerged
Dimensions: 73.6 x 7.6 x 6.4 meters (241 x 25 x 21 feet)
Propulsion: Turbo-electric, 1 reactor, 1 shaft, 9,500 shp, 25 knots
Crew: 66
Sonar: DMUX 20 multifunction, DSUV 62 towed
Armament: 6 21 inch torpedo tubes (14 Exocet & torpedoes)



Other very small ones:

Swiftsure class (United Kingdom)
Displacement: 4,500 tons submerged
Dimensions: 82.90 x 9.83 x 8.25 meters (272 x 32 x 27 feet)
Propulsion: 1 PWR.1 reactor, steam turbine, 1 shaft, 15,000 shp, 28 knots
Crew: up to 120
Sonar: Type 2020 bow, type 2007 flank, Type 2019 intercept, Type 2024 towed in some
EW: UAC intercept
Armament: 5 21 inch torpedo tubes (torpedoes, Harpoon, Tomahawk)

Project 091 'Han' class (China)
Displacement: 4,500 tons submerged (possibly 5,500 tons)
Dimensions: 90 x 9 x 7.25 meters/295 x 29.5 x 24.2 feet (98 x 9 x 7.25 meters/321.5 x 29.5 x 24.2 feet for last two)
Propulsion: Steam turbines, 1 reactor, 1 shaft, 12,000 shp, 26 knots
Crew: approx. 75
Sonar: Trout Cheek, DUUX-5 passive array
Armament: 6 21 inch torpedo tubes (18 weapons or 36 mines)

Project 705 'Lira' class, aka Alfa (USSR)
Displacement: 3800-4320 tons submerged
Dimensions: 79.5-81.4 x 9.5 x 6.9-7.6 meters/265-271.3 x 31.6 x 23-25.3 feet
Propulsion: 2 Steam turbines, 1 liquid metal reactor, 40-46,000 shp, 43-45 knots
Crew: 31-45
Armament: 6 21 inch torpedo tubes (18 weapons or 24 mines)



There are smaller nuclear powered submarines, but these are the smallest combat ones. All the ones below 2000 tons are actually for research and intelligence collection, and are too small to effectively operate weapons systems. It should also be noted that many of these are known for having reactor problems.
These submarines are roughly the size of a medium or large DE unit like the various Kilo models.

That was most helpful Clan Smoke Jaguar i thank you for your input.