What is North Korea's new solid-fuel missile -- named HS-18 ?

Norbert Brügge, Germany
 

2023, April, 13 -- The photos of the launch of that missile, wjich shown at the last parade, bring us closer to solving the mystery. It is a three-stage missile with a base diameter of 1.8 m and 1.5 m diameter in the upper part. The approximately 21.8 m long missile is referred as Hwasong-18. Because it is a solid-fuel missile, a name from the Pukguksong series would have been more appropriate. The exciting question is which existing missiles were stacked here. In any case, the size of the missile should not be overstated. In any case, the diameter of 2.10 or 2.20 m circulating in analyzes is out of the question.

Analysis:
At the moment I am assuming that for the new HS-18 use various new composite-casing motors, one such engine (PS180) of which has recently been shown on a test stand and has also been seen in various missiles on parades (e.g. PS -4, -5, -6). The first stage with a diameter of 1.8 m would therefore be a one segment lengthened PS180 motor from the PS-6 GLBM.
The barge-launched PS-3A (TR) with a diameter of 1.5 m (PS150) could -- also with extended motors -- represent the upper two stages of the HS-18.
Attention: This three-stage rocket can potentially also be used to launch small satellites.

TAn vehicle with huge canister for a solid-fuel missile shown at last parades in 2023 was a mysterium. North-Korea has not yet developed or tested such long motors with this diameter. Corresponding missiles are also not known.
Note: The recently tested motor PS180 was not a long motor and is only suitable for the PS-5 or PS-6.