When the Soviet Union fell apart, Ukraine was thought to have about 200 MiG-29 jets.
The information management system of aircraft's avionics suite had been changed so that it now has two digital computers which process information from the flight- and weapons-control systems.
In June 2019, Russia offered China a second batch of Su-35s.
The aircraft struck a barrier at the end of the runway and was destroyed by fire; the pilot ejected and sustained burn injuries.
The handover marked its official entry into operational service.
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