'Boramae' KF-21 Achieves Supersonic Flight Success After 6 Months

DAPA "Prototype No.1 Breaks Speed of 1,224 km/h"

[Asia Economy Reporter Jang Hee-jun] The domestically produced supersonic fighter jet 'Boramae' KF-21 prototype No. 1 has successfully completed its first supersonic flight. This is the first time an aircraft developed with domestic technology has broken the sound barrier.

The Defense Acquisition Program Administration (DAPA) announced on the 17th at around 3:15 PM that the KF-21 prototype No. 1 successfully performed its first supersonic flight.

The No. 1 aircraft took off at around 2:58 PM from the Air Force 3rd Training Flight Group located in Sacheon, Gyeongnam, and flew at an altitude of about 40,000 ft over the South Sea, breaking the sound barrier (Mach 1.0, 1224 km/h) for the first time. After a 56-minute flight, it landed at around 3:54 PM.

KF-21 Prototype No. 1 Taking Off from Sacheon Air Base
[Photo by Defense Acquisition Program Administration]

Since its maiden flight in July last year, the KF-21 has continuously expanded its flight envelope in terms of altitude and speed through more than 80 flights to date, and succeeded in supersonic flight on this day. The flight that first broke the sound barrier was piloted by Lee Dong-gyu, a senior pilot from Korea Aerospace Industries (KAI).

This is the first time an aircraft with an indigenous design developed using domestic technology has broken the sound barrier. Although the domestically produced supersonic advanced trainer T-50 (Golden Eagle) broke the sound barrier in 2003, it was developed through technological cooperation with the United States.

This flight confirmed that the KF-21 maintains structural stability of the airframe in the supersonic regime. When an aircraft exceeds Mach 1.0, shock waves occur on the wings and other parts of the airframe due to air resistance, and the surrounding airflow becomes unstable, which can significantly affect the structural integrity of the aircraft.

Regarding this, a DAPA official explained, "The KF-21’s ability to overcome shock waves and maintain normal flight while breaking the sound barrier demonstrates that structural stability of the airframe can be maintained in supersonic conditions."

KF-21 [Photo by Defense Acquisition Program Administration]

The defense authorities plan to further increase the altitude and speed of the KF-21 in the supersonic regime, while checking and verifying flight stability in the supersonic range, and continuously reflecting these results in the system development.

Defense Minister Lee Jong-seop said, "Thanks to the dedication and hard work of many people, we have finally achieved the historic accomplishment of possessing the first supersonic aircraft developed with domestic technology," and encouraged, "I sincerely thank all those who have worked hard, including Air Force and DAPA officials, the development team from Korea Aerospace Industries (KAI), and test flight pilots."

He added, "With this successful supersonic flight, our military has further solidified the foundation for building a science and technology-strong military," and "Moreover, we have achieved a great milestone in advancing one step closer to becoming one of the top four defense export countries."

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