North Korea’s New Missile: Not an ICBM

April 22, 2012
David Wright
Former contributor

Before North Korea’s failed launch a week ago, there was a lot of talk about the North unveiling a new long-range missile in its April military parade. As a result, when North Korea did display a missile body not seen before, people began calling it an ICBM. For example, yesterday the New York Times wrote:

During the parade in Pyongyang, the North’s capital, six trucks hauled what appeared to be a new type of intercontinental ballistic missile.

This idea seemed to be reinforced by the fact that it was carried on a larger truck than had previously been seen in North Korea, so people were left with the impression that “big truck = big missile.”

But the missile—even if real—is too small to be an ICBM using any of the technology North Korea appears to have.

The picture above shows, to scale, the new missile body (called the KN-08 in the west) on the left and the Unha-3 launcher on the right. The Unha-3 is about 30 m long and 2.4 m in diameter. The KN-08 appears to be about 18 m long and 2 meters in diameter.

If used as a ballistic missile, the liquid-fueled Unha-3 could likely carry a nuclear-weapon sized warhead to roughly intercontinental distances. If the KN-08 was also liquid fueled it would have a range much shorter than intercontinental. It simply could not carry enough propellant to reach the high speeds needed for a long-range missile.

So some people have asked whether it might instead be fueled by solid rather than liquid propellant. But North Korea does not have the ability to build long-range solid-fueled missiles. Its only solid-fueled missile is believed to be the Toksa—which appears similar to the Soviet SS-21 missile—with a range of about 100 km. And it is not clear whether Pyongyang has learned to produce even such a small solid-fueled missile or whether it purchased SS-21s.

In either case, producing large, solid-fueled rocket motors is a very significant technical challenge. For example, the propellant must be rigid enough to support its own weight, but must not be so hard and brittle that it forms cracks, which can cause the propellant to explode when it burns. These requirements are especially demanding for a mobile missile, since the propellant must be able to withstand the additional stresses associated with moving. China only built a road-mobile solid-fueled ICBM recently, after several decades of development. This appears to be well beyond North Korea’s capability.

I have not been able to identify any known missile with the same size and shape as the KN-08 that it might be based on. Some people have claimed a resemblance to the Chinese DF-31 road-mobile ICBM, but they do not have the same length, diameter, or shape, so that comparison is pretty meaningless.

Is the KN-08 Real?

An analysis by two German missile experts of the six KN-08 missile bodies seen in the parade in Pyongyang leaves little doubt that what was seen in the parade were mockups—and not terribly good ones.

The question then is whether these were simply Potemkin missiles paraded with the hope of gathering press like the excerpt from the New York Times above, or whether they represent mockups of an actual missile that is being developed. If it’s the latter, there are several things to keep in mind:

  1. As the German analysis shows, the six mockups in the parade differed from one another in the placement of key parts, etc., and appeared to show contradictory details, such as ports appropriate for filling liquid propellant tanks but also channels for electric cables that are appropriate to solid engines. This suggests there either is no underlying design, or the design is so preliminary and schematic that it does not flesh out basic details.
  2. If a real development program exists and the missile is liquid fueled, then it is possible that the missile could appear in the coming years, but it would not be a long-range missile, as discussed above.
  3. On the other hand, if the mockups indicate an interest in developing a solid-fueled missile with potentially ICBM range, then that missile cannot be expected to appear any time soon for the technical reasons discussed above.

The KN-08 Transporter

The truck seen carrying the KN-08 in the recent parade has drawn a lot of attention in the past week.  The missile transporter (top photo below) appears to be a modified version of a large Chinese truck (lower photo below).

This raises questions about whether China violated UN sanctions against North Korea by selling it trucks of this kind. If China modified the truck by adding the bed that carries the missile it would be a clear violation, but it may well be that the same people in North Korea who built the mockups built the bed. Whether this is a violation of sanctions will probably depend on details like who China thought it was selling the trucks to, assuming the transaction was handled by a North Korean front company. UN experts will have to sort this out.

But it is important that people not conflate the truck and the missile and jump to the conclusion that China was involved in developing the KN-08 missile. I have not seen anything yet related to the missile that suggests Chinese involvement. As noted in our previous analysis, the technology we see throughout the North Korean rocket programs appears to be of Soviet/Russian origin, not Chinese.

“Mobile” vs. “Moveable”

Finally, as I’ve pointed out before, it’s important to understand what it means to put a large liquid-fueled missile on a transporter. Because these missiles are so large and heavy and the rocket body has very thin walls, they would be transported without fuel in them. They could then be transported to a location, erected, loaded with fuel, and  launched.

Making missiles “moveable” can be useful since it means they are not tied to a known launch site. But a liquid missile would have to be serviced by a fleet of trucks carrying the fuel (about 70 tons of fuel for a rocket the size of the Unha-3). And it would likely take a couple of hours to prepare for launch by erecting and fueling the missile, during which time it would be vulnerable.

This is different from what people usually think of as a “mobile” missile, which is assumed to be fueled when it is transported, so that it can quickly get into position, be erected, and fired.