After one year and a half of war, none of the belligerents achieved to take the upper hand in the air. Air superiority in the Ukrainian sky is still denied to Russia. Why is the Russian Aerospace Force (VKS), theoretically superior by number and by equipment, having difficulties against the outnumbered Ukraine Air Force? What conclusions should Europeans armies draw from this modern interstate war?

Prior to the start of the invasion by Russia, the Ukrainian Air Force was already in bad shape, it was under the process of cannibalisation for maintenance due to the non-renewal of its fleet, and it also suffered some casualties during the eight years of the Donbas war (Airheadsfly, 2014). In February 2022, its fighter air force was mainly composed of 51 Mig-29 and 32 Su-27 (Flight Global, 2023), which are less advanced versions of the modernised Russian ones with inferior radar range capabilities. Ukraine has had high casualties since 2022; up to this day it lost 22 Mig-29 and 12 Su-27, which is roughly half of their fighter fleet (Oryx, 2022).