A significant blow was dealt to Moscow's air power last week after Ukraine claimed it had shot down one of Russia's long-range surveillance aircraft near the Sea of Azov.
Ukraine also claimed it had badly damaged a Russian air force IL-22.
The Russian Beriev A-50 usually operates with a crew of 15 people and provides long-range radar surveillance across the battlefield.
Unlike ground-based radars which have a limited line-of-sight due to the curvature of the earth, the Soviet-designed A-50, nicknamed "Mainstay" by NATO, can detect enemy aircraft and missiles up to 400 miles away.
So how did Ukraine successfully target a pair of Russian aircraft that should have been aware of any Ukrainian threats long before they got close?
Our military analyst Sean Bell, who is a former fighter pilot, said in his RedMatrix podcast this week that this apparently successful attack demonstrated "a major victory for Ukraine against their Russian adversary".
He noted that Russian military did not deny it had lost an A50 and that evidence had emerged of a "badly damaged IL-22 that landed shortly after the incident".
"Russia could have shot down the aircraft by mistake, but in the circumstances that would be a particularly grave error," he said.
The military expert admitted that "we will probably never know the full details of the loss of these Russian aircraft" but it did share parallels with the successful Ukrainian targeting of the Russian Moskva on 14 April 2022, which saw Ukrainian missiles sink the vessel in the Black Sea.
Although the actual circumstances of the recent loss are subject to conjecture, Bell suggested it was "quite possible that the Russian A50 was lost to the US-provided Patriot missile system".
So why did the Russian aircraft not sense the Patriot system and steer clear?
Bell explained that if the range of the missiles was known, then Russian aircraft can plan to "avoid flying too close", but in this case the Ukrainians might well have improvised and "used an air picture from another radar source, thus not betraying the location of the missile system itself".
This could lead to the pilot of the Russian aircraft believing it was out of range of the Patriot missile system.
But whatever the tactics employed by the Ukrainians, Bell suggested "it should have been eminently capable of avoiding the Ukrainian strike".
Listen to Bell's RedMatrix podcast here.
