China has delivered three anti-aircraft missile systems in a covert delivery to Serbia over the weekend in what is believed to be the biggest overseas airlift using the Chinese Y-20 transport planes. This is reportedly part of Serbia’s efforts of bolstering its military capabilities through a purchase deal that also includes drones.

Serbia, a Russian ally, purchased these missiles in 2020 together with the CH-92A attack and reconnaissance drones. It had received its attack drones in 2020, which made Serbia the first country in Europe to field the Chinese-made UAV. The recent delivery was reportedly a battery of FK-3 medium-range surface-to-air missiles (SAM), the export version of the HQ-22 SAM system. However, the exact contents of the cargo could not be independently verified. However, Hong Kong-based military expert Liang Guoliang said that Serbia bought three FK-3 missile systems, three launcher vehicles, a command vehicle, and additional missiles. He also estimated that it would need to be delivered with 12 Y-20 planes.

These missiles can reportedly fly up to Mach 6, with a range of 93 miles. In comparison, the HQ-22 variant has a longer range of 105 miles. Each FK-3 system is composed of 3 launch vehicles with 4 missiles with a radar vehicle. The missiles are reportedly equipped with a semi-active radar CNS, a two-way radio command line for data transmission, with its flight controlled by a combined guidance system. Its track-via-missile method enables the missiles to have reduced sensitivity to electronic countermeasures, making them more difficult to shoot down. It’s reported that each battery of the missile system can engage 6 targets simultaneously.