The South Korean domestically produced KF-21 4th++ Generation Fighter took its first flight today from an air force base in Sacheon, about 185 miles south of Seoul, and completed a flight of more than 30 minutes, the Defense Acquisition Program Administration (DAPA) said in a statement.

The DAPA told press that they are planning another 2,000 hours of developmental hours before the aircraft will be delivered to the armed forces.

The KF-21, developed by Korea Aerospace Industries is the result of a $6.67 billion project, which is meant to replace the aging fleet of F-4 and F-5 fighters while being a cheaper than the American F-35 Lightning II stealth jet, which the Korean Air Force flies.

It is important to note that the KF-21 is not a fifth generation fighter like the F-35 because it is missing several components  that define fifth generation, such as data fusion of sensors and advanced stealth capabilities. Fifth generation fighters are designed to be stealthy from the ground up with radar absorbent materials and design. Unlike 4++ which receive upgrades in materials to make them more stealthy. The F-35 has a remarkably smaller radar-cross-section (rcs) than the KF-21, meaning it looks much smaller on radar due to the aforementioned characteristics. The KF-21 will also not have internal weapons bay.

At least 40 aircraft are planned to be delivered by 2028, with South Korea expecting to deploy a total of 120 of the aircraft by 2032.