Ukraine and Russia are both still flying Soviet-era warplanes, including fighters, bombers and interceptors. Which is why the US purchase of 81 such combat aircraft from former Russian ally Kazakhstan such a threat.
The planes will reportedly be given to Ukraine as replacements, decoys or a source of spare parts, as well as the psychological warfare benefit of having Russia know it's been defied by another former vassal state. JL
Rebecca Rommen and Thibault Spirlet report in Business Insider:
The US has acquired 81 Soviet-era combat aircraft from Kazakhstan, including MiG-31 interceptors, MiG-27 fighter bombers, MiG-29 fighters, and Su-24 bombers from the 1970s and 1980s. The declared sale value was one billion Kazakhstani tenge, or $2.26 million, an average value for each plane of $19,300. The aircraft could be used in Ukraine, where similar aircraft are in service, given Ukraine's continued reliance on Soviet-era weapons. The aircraft could serve as a source of spare parts or be deployed as decoys. Since Russia invaded Ukraine, Kazakhstan is aligning itself more with the West, drawing the fury of some in Russia.