North Korea's advanced drones were inspected by Kim as a launch of a solid fuel IRBM (2024.01.15)
North Korean state media has described the Saetbyol-4 (Morning Star-4) as “a strategic reconnaissance drone,” according to the International Institute for Strategic Studies (IISS). The Saetbyol-9 (Morning Star-9) has been labeled a “multi-purpose attack drone.” North Korean state media first unveiled the two drones in July 2023 and provided brief videos showing both of them in flight.
Both were formally revealed during the Weapons and Equipment Exhibition 2023 July 26, 2023, attended by Kim and Russian Minister of Defense Sergei Shoigu. Shoigu was visiting Pyongyang to further military cooperation between the two countries and to secure more North Korean-made armaments for use in Moscow’s war in Ukraine. The precise capabilities of these North Korean drones were very much unclear, and few details have emerged since.
Image from the test of the solid fuel IRBM and hypersonic vehicle. (2024.01.14)
The test-fire was aimed at verifying the gliding and maneuvering characteristics of intermediate-range hypersonic maneuverable controlled warhead and the reliability of newly developed multi-stage high-thrust solid-fuel engines,” was successful.
“The test-fire never affected the security of any neighboring country and had nothing to do with the regional situation,” according to KCNA. However, an IRBM, which has a range of between 3,000 and 5,500 kilometers [1,864 to 3,418 miles], would place the U.S. territory of Guam within range if fired from Pyongyang, the South Korean Yonhap news agency noted in its story about the test. Kim has threatened to fire an IRBM near Guam in the past and North Korean IRBMs have been a top reason why a THAAD anti-ballistic missile battery has been deployed to Guam for years.
Sunday’s test comes after KCNA reported on engine trials for a new solid-fuel intermediate-range ballistic missile (IRBM) conducted at separate facilities on both coasts last November, according to NKNews.org.
South Korea’s Joint Chiefs of Staff (JCS) detected the latest launch at around 2:55 p.m. KST on Sunday, “saying it appeared to be an intermediate-range ballistic missile (IRBM) that flew around 621 miles (1,000 km) into the Sea of Japan (East Sea),” according to NKNews, North Korea tests missiles at extreme altitudes in order to stay closer to the peninsula. The performance during these tests can be extrapolated into a shallower, down-range optimized, operational trajectory.
While North Korea has recently developed other solid fuel missile designs, including recently demonstrating a solid-fuel ICBM for the first time, having an IRBM with this capability is especially noteworthy. They would be among the most threatening missiles to U.S. interests during a conflict.
Solid fuel capability means they can be erected and launched far quicker than their liquid-fuel progenitors. This makes them much harder to strike preemptively and gives less time for realizing an attack may be imminent. As such, solid fuel ballistic missiles increase the North Korean ballistic missile arsenal's survivability, effectiveness, and flexibility, among other advantages. North Korea has been on a quest to develop solid fuel designs for years and has made remarkable progress in this area of rocketry since it began a campaign of rapid iterative missile testing in 2016.
The hypersonic boost glide vehicle (BGV) supposedly mounted atop the missile is a whole other issue. North Korea claimed it tested a BGV in 2021. It has since claimed to have tested similar vehicles multiple times atop various missiles, but putting one on a solid-fuel IRBM would drastically increase the value of such a weapon.
Yet much is still unknown about the viability of North Korea's BGV designs and if they would even withstand the voyage to their target area. The technologies behind hypersonic flight, and especially those needed for dynamically maneuvering at velocities in excess of Mach 5, are very hard to master. If North Korea can make it work, especially aboard a solid fuel IRBM, that would be a major development that would significantly complicate defending against incoming North Korean attacks.
A graphic showing, in a very rudimentary way, the difference in trajectories between a traditional ballistic missile and a hypersonic boost-glide vehicle.
There is also some debate over if at least some of these conical, finned, hypersonic vehicles are really just maneuvering reentry vehicles that are less capable of higher degrees of maneuverability. Hypersonic terminal velocities are not abnormal for ballistic missiles, especially IRBMs, so the vehicle would be hypersonic, regardless, but not having the same capabilities of a HBGV. Still, this would be a troubling development, but nothing as big of accomplishment as making an operationally relevant hypersonic BGV.
Regardless, Kim's inspection of the advanced drones and the solid fuel missile test come at a perilous time on the Korean Peninsula. On Monday, he called for a constitutional amendment to change the status of South Korea as a separate state and warned that while his country doesn't seek war, it didn't intend to avoid it, KCNA reported, according to Reuters.