Speculation continues surrounding the true and near future capabilities of the North Korean nuclear and ballistic missile programmes. There is no serious doubt that North Korea is now a nuclear power, and that they possess various forms of ballistic missiles, but the extent to which they have been able to marry the two is still somewhat contentious.
Really really brief backstory
Most of North Korea’s ballistic missiles are derived from the Soviet SCUD system which they obtained from Egypt. These missiles have been improved and ultimately resulted in crude medium/long range ballistic missiles.
Although the SCUD family of missiles could (and has in the past) been converted for naval launch (submarine or ship), they have relatively dangerous fuels that make storage and launch less robust than modern ballistic missiles.
Perhaps with this in mind North Korea has attempted to gain more modern ballistic missile technology as demonstrated by the 1993 arrest of a team of submarine-launched ballistic missile (SLBM) scientists recruited from the Russian Makeyev missile design bureau.
Also North Korea has obtained elements of R-27 (SS-N-6) technology which probably includes the solid fuels better suited to naval deployment.
Golf-II Class Ballistic Missile Submarine
Dimensions: L 98m, W 8.2m, Displacement 3553t (submerged)
Max speed: 15-17kts surfaced, 12-14kts submerged.
Ballistic Missiles: 3 x ballistic missiles, probably modified Nodong-I (related to SCUD, Nodong-I has a maximum range of about 1,300km and theoretically could be modified to carry a nuclear warhead)
Torpedoes: 6 x 533mm (21”) heavyweight torpedo tubes.
Crew: 83
Russia sold 10-12 decommissioned submarines to DPRK in 1993 with deliveries in subsequent years. The exact make-up of the delivery is open to speculation but it was widely and consistently reported to include a number of functional Golf-II class ballistic missile submarines. Generally accepted figure for Golf-IIs involved in the sale is 10.
Although Russia maintains that the submarines were to be dismantled under Russian supervision, it was widely thought that DPRK would attempt to bring one or more back into service, possibly by means of cannibalization. The Golf-IIs carried SS-N-4 ballistic missiles in Russian service.
Most observers do not believe that any of the subs have been returned to service but the possibility remains and there doesn’t seem to be any public domain evidence to confirm either viewpoint.
The north Korean Nodong-I missile is related to the SS-N-4 via the SCUD, but is about 1m longer which means that either the missile or the hull would have to be modified to accommodate it, but this is not all that far fetched.
Unlike modern ballistic missile submarines the Golf-II is a diesel-electric boat which limits its time underwater relative to other countries SSBNs but on the other hand the technology to maintain and operate these boats is well within DPRK’s means relative to nuclear boats. The submarine was designed for underwater launch of the missiles, from depths of up to 50m and speeds of up to 4kts and a firing interval of about 5minutes. Pre-launch time was about 45minutes. Even assuming lower operational specs for returned-to-service DPRK Golf-IIs with Nodong-I, we are still talking about a credible is crude SSBM capability.
It is widely speculated that a far more logical way to deploy a ballistic missile is by using medium/large merchant ships as launch platforms. North Korea operates and builds ocean going merchant ships. The missiles could be hidden amongst transport containers.