As Russian cruise missiles sped towards their target this month, a Ukrainian pilot gave chase in an old Soviet MiG-29 fighter jet and locked onto two of them, but could not take the shot: they were nearing a large town and it was too risky.
He said he passed the targets on to Ukraine's ground-based air defences which shot them down, as they have done hundreds of missiles since October, blunting the impact of a Russian air campaign that aims to destroy the country's power grid.
"Fortunately for us, they succeeded," the 29-year-old pilot, whose codename is Juice, told Reuters, describing the Dec. 5 incident.
Such skirmishes are common in the skies over Ukraine, and their outcomes have a direct bearing on the lives of millions of people who are left without heat, power or running water during the freezing winter if defences fail.
Ukraine calls the attacks a war crime, aimed at cowing innocent civilians. Russia says the electricity grid is a legitimate military target in its "special operation".
The Pentagon has said Russia's missile strikes are partly designed to exhaust Kyiv's supplies of air defences and finally achieve dominance of the skies above the country.
Ukrainian President Volodymyr Zelenskiy travelled to Washington on Wednesday to seek "weapons, weapons and more weapons", including a Patriot missile battery that would shore up the country's defences against incoming missiles and drones.
The attacks on energy targets disrupt everyday life, including vital services like hospitals and schools, and threaten to further cripple the economy. It is already set to shrink by at least a third this year, as shops and heavy industry struggle to keep the lights on.
Russia has launched nine, large-scale air attacks - usually firing more than 70 missiles at a time - since Oct. 10, knocking out power, running water, mobile signals and heating.
Ukraine's record of downing missiles has ranged from around 50% to as much as 85%, with more recent attacks coming closer to the higher end, according to Reuters calculations based on Ukrainian data.
After the most recent attack on Friday it said it had shot down 60 out of 76 incoming missiles.
Still, those which come through inflict serious damage. Ukraine was forced to implement emergency blackouts nationwide, and much of Kyiv region has been without power and water for several days.
Spread thinly across a country double the size of Italy, air defence units are deployed mostly near cities and key infrastructure, while fighter pilots like Juice cover the expansive gaps in between.
It is a tall order. Juice says he has not shot down a single drone or missile in his MiG-29, which came off the assembly line before Ukraine won independence from Soviet Moscow in 1991.
"Our jets are not capable enough to do that efficiently," said the pilot, who is in a constant high state of readiness at a location in central Ukraine that he would not disclose.
He said it was hard spotting incoming targets with old radars, especially in the case of low-flying, slow-moving Shahed drones that look like moving trucks on the radar screen.
On occasions, like Dec. 5, Juice was unable to fire at targets because he was too close to densely populated areas.
It is ground-based air defence units that shoot down the vast majority of missiles and drones, not ageing warplanes, Air Force spokesman Yuriy Ihnat said.
"Both missiles and drones fly along the course of rivers to be as low as possible and disappear from radars. If they are low enough, they just disappear ... Then they pop up again; it's a game of cat and mouse," said Ihnat.
After major missile barrages, a days-long pause tends to follow as Russian intelligence assesses what was hit and what was missed, tracks the repositioning of Ukrainian air defences and looks for weak spots to exploit, Ukrainian officials told Reuters.
"Air defences don't remain in one place: we can't cover the whole country..." Ihnat said.
For Ukraine, intelligence gathering by both domestic and Western spy agencies plays a major role in preparing for Russian air strikes, Denys Smazhnyi, a senior air defence training official, told Reuters.
"So we usually know what objects are under attack, we can build around those objects some kind of air defence," he said.
Ukraine's military intelligence chief has estimated that Russia may only have enough high-precision weapons for few more major air strikes.
But Ukrainian officials also acknowledge that their own stocks of defensive weapons are dwindling as the invasion nears the 10-month mark.
Despite Western supplies of air defence systems to Ukraine including the sophisticated U.S. NASAMS and German IRIS-T systems, Soviet-era systems make up the core of Ukrainian air defences, said Ihnat.
"Our Soviet air defence system is being depleted - that is the S-300 and the BUK, which are the foundation. We cannot maintain that indefinitely because all the unique spare parts of those systems are made in Russia," he added.
Western air defence systems supplied to Ukraine have performed well, but supplies are far short of what is needed, according to both air force officials.
"The Russian equipment is getting older; we are losing missiles. I'm not (saying) they will run out in a few days or a few weeks ... It will still depend on the intensity of the Russian attacks," said Smazhnyi.
By Dec. 7, Russia launched more than 1,000 missiles and rockets at Ukraine's power grid, its operator said.
On Wednesday, the United States announced $1.85 billion in additional military assistance for Ukraine, including a transfer of the Patriot Air Defense System, Smazhnyi said such systems would provide protection against ballistic missiles that Ukraine is now exposed to.
Ihnat said IRIS-T production was already at maximum capacity and that Ukraine should therefore focus on obtaining as many NASAMS supplies as it could.
"We're almost through one month of winter, we have one more and then February, which is short. I think we'll survive. But it's better to supply missiles than generators," he said.
Juice, who speaks fluent English, said many of his peers in the Air Force were taking English lessons in their free time in anticipation that Ukraine would one day receive Western aircraft such as the U.S. F-16 multi-role fighter jet.
There has been no sign that any delivery of F-16 was imminent or agreed, and Ihnat said the pilots were acting on their own.
"Everyone understands that sooner or later we will switch to F-16s or some other type of plane and English knowledge will be needed."
