The Defense Acquisition Program Administration said the KF-21 successfully carried out its first supersonic flight at 15:15 on January 17, 23.
For the first time, KF-21 Tester 1 broke through the speed of sound (Maha 1.0, about 1,224 km/h) as it took off from the Air Force's 3rd Training Fighter Wing (Sacheon) and flew at an altitude of about 40,000 ft over the South Sea.
The success of the KF-21 supersonic flight has two important implications for aircraft research and development.
First, it has been confirmed that KF-21 has the structural stability of the gas in the sound speed domain through adequate speed breakthrough flight.
When an aircraft breaks Mach 1.0, shock waves are generated in the airframe such as wings due to air resistance.The surrounding air flow is unstable, which can have a significant impact on the structural soundness of the aircraft. The fact that KF-21 flew normally by overcoming shock waves when breaking through the sound speed shows that the structural stability of the gas can be maintained at supersonic speed.
Second, it is the first successful sound speed breakthrough for an aircraft with an independent shape developed with domestic technology. In the past, there was a case in which the domestic supersonic advanced trainer T-50 (Golden Eagle) broke through sound speed in 2003.But it was developed through technical cooperation with the United States. With the supersonic breakthrough of the KF-21, Korea has finally made a supersonic aircraft fully domestically.
In the future, KF-21 plans to further increase its altitude/speed in the sound area, check/verify flight stability in the supersonic section, and continue to reflect various factors in the system development to make KF-21 a true supersonic fighter.