NORTH KOREAN NUKESUnderwater Nuclear Drone: North Korea’s Nuclear Madmen
One remarkably irresponsible claim by Kim Jong Un is North Korea’s announced testing of an underwater drone that it states can carry a nuclear weapon, able to infiltrate enemy waters and create a deadly radioactive plume of water. Such a detonation could severely contaminate ships and port cities with intense radioactive fallout mixed with water.
David Albright of the Institute for Science and International Security has just issued a brief analysis of underwater nuclear drones, the weapon system North Korea has tested, according to Kim Jong Un.
Here is Albright’s analysis:
One remarkably irresponsible claim by Kim Jong Un is North Korea’s announced testing of an underwater drone that it states can carry a nuclear weapon, able to infiltrate enemy waters and create a deadly radioactive plume of water. 1 Kim’s parallel claims of the weapon creating a deadly tsunami can be seen as hyperbole; perhaps he is confusing a tsunami with the radioactive waterfall following the lifting of immense amounts of water into the atmosphere by an underwater nuclear explosion. Nonetheless, such a detonation could severely contaminate ships and port cities with intense radioactive fallout mixed with water.
Of course, North Korea’s ability to put a nuclear warhead into an underwater drone should not be taken as given; the announced test involved conventional explosives only. The warhead diameter can be roughly estimated by scaling from the head of a gleeful Kim next to an alleged underwater drone (Figure 1). This process gives an estimated diameter for the drone system in the range of 40 to 50 centimeters. This diameter could conceivably hold a pure fission weapon, but it is on the small size and would likely have a yield in the range of 10-25 kilotons. For comparison, Iran’s best known nuclear weapon design had a diameter of 55 centimeters and an expected yield of ten kilotons. Given North Korea’s underground testing experience, their weaponeers may be able to achieve the necessary level of miniaturization for outfitting an underwater drone with a nuclear weapon, but just as likely, North Korea cannot do so without additional underground nuclear testing aimed at reducing the diameter of the nuclear warhead while maintaining its explosive yield.
Operation Crossroads
It is worth reviewing the first underwater nuclear detonation, an unexpected radioactive disaster that occurred during Operation Crossroads in 1946. Crossroads was planned to involve three successive nuclear explosions over or under the Bikini Lagoon in the South Pacific and a host of warships placed around the lagoon as “target” vessels. The second test, codenamed Baker, was a 21 kiloton fission explosion detonated 90 feet underwater.
