[Yang Nak-gyu's Defence Club] Why Is There a Difference in Ballistic Missile Range Between North and South Korea?

North Korea's Korean Central TV released photos on the 11th showing the launch of two short-range projectiles conducted the previous day in the Hamhung area of South Hamgyong Province. The military initially estimated these projectiles to be of a type similar to the Iskander-class KN-23 short-range ballistic missile, but the photos released by North Korea suggest that they are a new type of ballistic missile different from the KN-23. The photos show the launch scenes released by Central TV that afternoon. (Photo by Yonhap News)

[Asia Economy Yang Nak-gyu, Military Specialist Reporter] There is growing interest as North and South Korea show differences in the range of the ballistic missile recently launched by North Korea. The military authorities announced that the range of the ballistic missile launched by North Korea was 450 km, but North Korea stated the next day that it was 600 km.

On the 30th, the military said regarding the range difference between the two Koreas, "At that time, our military explained based on the initial information detected by our detection assets," and added, "Currently, under close cooperation between South Korea and the U.S., we are conducting a precise analysis by synthesizing information from various sources."

When North Korea launches a missile, South Korea and the U.S. analyze the speed and distance of the detected segment through radar, etc., to estimate the expected range. The missile launched by North Korea is first detected by the ‘Green Pine’ ballistic missile early warning radar deployed on the ground and the SPY-1 radar equipped on the Navy’s Aegis destroyers.

However, if the missile is launched in the opposite direction from the radar location, as if launched toward the northeast direction this time, a ‘radar loss altitude’ (shadow zone) occurs below a certain altitude where detection is not possible. It is a kind of ‘blind spot.’ Due to this blind spot, there may have been errors in the initial evaluation by the South Korea-U.S. military authorities.

Inside and outside the military evaluate that if a ‘pull-up’ maneuver (raising altitude again in the latter part of flight) was performed at the radar loss altitude, the actual range could be longer than the military authorities’ estimate.

This also happened when North Korea launched two KN-23 short-range ballistic missiles toward the northeast direction around Wonsan Hodoban Peninsula on July 25, 2019. At that time, the Joint Chiefs of Staff announced that the first missile flew 430 km and the second 690 km, but later corrected that both missiles flew about 600 km after tracking the trajectory below the radar loss altitude through U.S. detection assets.

On the other hand, North Korea is known to measure the trajectory of the missiles they launch by capturing signals transmitted from ground remote telemetry equipment.

Shin Jong-woo, a senior research fellow at the Korea Defense and Security Forum (KODEF), said, "Unlike the existing Scud, the improved KN-23 can perform low-altitude gliding flight below radar detection altitude in the terminal phase," and added, "The radar detection restricted zone may have been longer than intelligence agencies predicted, which could have caused errors in range estimation."

This content was produced with the assistance of AI translation services.