KYIV, Ukraine — President Volodymyr Zelenskyy said recently that Ukraine's military had shot down its 200th Russian aircraft — a figure few would have believed before the war began.
"Russia has not lost so many aircraft in any war in decades," Zelensky said in his nightly video message last Friday.
That number can't be independently verified. Still, it points to one of the most striking facets of the war: instead of dominating the skies as expected, Russian pilots are so vulnerable they're reluctant to enter Ukraine's airspace.
Here are some of the reasons Russia has so underperformed in the air, while Ukraine has overachieved.
Q. Going into the war, the consensus was that Russia would carry out major air operations and potentially deliver a knockout blow to Ukraine. What happened?
To answer that question, I took a short drive outside Kyiv today. Russia was so confident of its air power that on the first day of the war, Feb. 24, it sent around two dozen helicopters loaded with paratroopers to take the Hostomel Airport — a military and cargo airport — less than 10 miles northwest of the capital.
Russia's planned to secure the base, then call in many more troops to land there, with the intention of seizing Kyiv within days.
But the Russians were beaten back in several days of heavy fighting. The airport is a graveyard of burned out buildings and charred vehicles stacked on top of each other. But Ukrainian troops are at their base, civilians are combing back into the ravaged town. This episode set the tone for Russian air operations that have fallen far short of expectations.
Q. That was just one battle. Russia has far more war planes, and far more modern aircraft, than Ukraine. Why isn't this translating to a Russian military advantage over time?
The Russians are believed to have at least 15 military aircraft for every one Ukraine has, and some estimates say the balance is even more lopsided.
Yet from the start, Russian war planes and helicopters have been getting shot out of the sky. Russian pilots quickly became risk-averse. Sometimes they briefly venture into the air over Ukraine to briefly fire their weapons — but there are many cases where they shoot from afar, without ever entering Ukraine.
"They're staying over the Black Sea, or they're staying in Russia and firing guided missiles. They simply are not comfortable flying in Ukraine for any extended period of time," said Professor Phillips Payson O'Brien, a military expert at the University of St. Andrews in Scotland. "That means they can drop bombs, they can launch missiles, but they can't control the airspace over a battle."
Q. It sounds like Ukraine is doing most of the damage from the ground with its air defense systems. Is that the case?
Yes, but their air defenses were relatively limited, especially when the war began.
The Americans have helped with large numbers of Stinger missiles. A single soldier fires these missiles from his shoulder, and they're very effective at taking down low-flying helicopters.
But perhaps Ukraine's most under-appreciated weapon in this war is the S-300 surface-to-air missile system. This is a hulking, Soviet-era air defense system that fires missiles from the ground that take down jet fighters.
Ukraine has a relatively small number — and it's not saying how many. Russia has apparently taken some of them out — and desperately want to eliminate all of them, but it hasn't been able to do so.
"Those are incredibly important to Ukraine," said Obrien. "They don't threaten every Russian flight. They can't threaten every flight. But they can make the pilots jumpy enough that anywhere they want to fly there's a potential threat."
Q. How are these developments playing out on the main battlefield in eastern Ukraine?
If Russia controlled the skies, its planes could hang out, loiter over the combat zone and target Ukrainian troops whenever they spot them. This would make Ukrainian ground forces very vulnerable, and they would have to worry constantly about being hit from the air.
But the Ukrainians have been able to move around far more freely than expected at the beginning of the war.
Russia is still bombing from long distance and inflicting great destruction. But this isn't nearly as accurate or effective as having planes directly over the battlefield for extended periods, where they can adjust to the situation on the ground.
In the capital Kyiv, Russian troops were within 10 miles of the city during the early weeks of the war and airstrikes were a regular occurrence. Now life is returning to normal in many ways — shops are open, people are on the street, traffic jams are becoming commonplace.
Residents are still closely following the war, but the fear of a Russian attack has diminished greatly in the capital.
Greg Myre is an NPR national security correspondent. Follow him @gregmyre1.