North Korea Planning Nuclear Powered Submarine

Hermit Kingdom Plans Nuclear Powered Submarine

Flag At the 8th Congress of the Workers' Party of [North] Korea which started on 5th January 2021, Kim Jong Un revealed plans for North Korea to build a nuclear submarine. He said that the plans were almost complete. It is a bold ambition for a country whose submarines are decades behind cutting edge.

Despite the monumental challenges involved in building nuclear submarines, we should be careful not to dismiss the Hermit Kingdom’s claims out of hand. North Korea’s nuclear submarine does not have to be anything as large, complex, or sophisticated as the latest types from leading navies. Or as expensive.

It is worth reflecting that the first nuclear submarines, the USS Nautilus and Soviet NOVEMBER Class, were built over 60 years ago. They were designed and built in a fraction of the time modern submarine programs take. And they worked first time. So the North Korean submarine could be essentially a vintage level of technology.

It could have many of the advantages of nuclear submarines. High underwater speed and virtually unlimited range. Yet it would still be a crude boat. It would likely be noisy and lack combat effectiveness when compared 1:1 to other subs. But this does not make it harmless, far from it.

North Korea may not currently have an operating nuclear reactor, but that do have experience. Nuclear power is not a mystery to them. It does not seem a push to suggest that North Korean scientists could, if they were ordered to, deliver a nuclear power plant.

North Korea Planning Nuclear Powered Submarine - Gorae Class
The most impressive submarine built by North Korea to date is the Gorae Class. It uses conventional diesel-electric drive.

What will the submarine be like?

A nuclear submarine implies something larger, at least in hull diameter, than most of North Korea’s locally built boats. North Korea has been indigenous building submarines since the 1980s but suffers on both the materials and technologies fronts. The current emphasis seems to be on ballistic missile submarines, but the latest type is actually a modified Romeo-Class boat. This submarine was obsolete long before it was converted. North Korea therefore has several options:

A. new-built design with a pressurized water reactor (PWR). This would be at least as large as the indigenous Gorae Class, and may require an even larger hull diameter.

B. Conversion of an existing submarine, most likely a Romeo Class. This may require a whole new stern section. The bow section of this type may not be suitable for higher underwater speeds however.

C. Build a very small nuclear powerplant either for midget submarines or as a form of AIP (air independent power) for conventional submarines. This latter concept is sometimes described as a ‘tea kettle reactor’. This would fit the claim of being a nuclear submarine but is a whole different kettle of fish.

My bet is that North Korea will want to put a ballistic missile on the submarine, so straight to SSBN. This is the same path as France and India in the past. If the North Koreans do go for an attack submarine (SSN) instead, this may have more to do with costs than ambition.

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The single biggest asset that they have in my view is determination. The absolute control that the North Korean regime enjoys, and its willingness to place military objectives ahead of even basic human needs of its population, is a formidable combination. If Kim wants a nuclear submarine his yards can build him one, despite the odds.

Everything North Korea has achieved in its advanced weapons programs, whether submarines, warships or missiles, has been done against the odds. A nuclear powered submarine will still take many years to build and test however, so more non-nuclear submarines will be built in the meantime.

There is also the possibility that the technology may be shared with Iran who also have ambitions in this space.

All this has led to another round of rumors and reports that South Korea will also consider building a nuclear powered submarine. South Korea has a booming submarine construction program, principally built from a German technology transfer. Their indigenous submarines are highly capable and highly modern. It seems much more within their technical reach than North Koreas. But the political will will have to be there.

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