The fires at the Kapotnya refinery were out by Sunday afternoon. The damage to Russian civil aviation took two more days to count.

According to the aviation security firm Osprey, the Ukrainian drone attack on Moscow overnight from 19 to 20 September delayed more than 400 flights and pushed over 30 aircraft to alternate airports. Some of those diversions were not short hops. Aircraft ended up at Kazan, Samara and St Petersburg, hundreds of kilometres from where their passengers had expected to land.

All four of Moscow's airports restricted arrivals and departures: Sheremetyevo, Domodedovo, Vnukovo and Zhukovsky. For a few hours on the final day of Russia's parliamentary elections, the capital of a country spanning eleven time zones was, aeronautically speaking, shut.

What the airlines actually lost

Osprey's tally is the one that matters for anyone in the business of moving passengers. More than 400 delayed departures and arrivals. More than 30 diversions. Four airports on restrictions simultaneously. Early Russian reporting that morning put the disruption at around 100 flights; the fuller picture, assembled once the day had finished unwinding, was four times that.

A diversion to Kazan or Samara is not an inconvenience that a schedule absorbs quietly. It strands crews outside their duty limits, parks aircraft where the operator has no engineering support, and displaces the next three rotations that airframe was supposed to fly. Osprey's warning, given the frequency of these attacks, was that disruption to Russian air traffic should be treated as an ongoing condition rather than an occasional event.

That is the part worth pausing on. Not one airliner was hit. Ukraine did not need to touch a single civil aircraft to take four international airports off line.

Plan “Carpet”, and why one drone empties the sky

When a drone is detected near a Russian airport, the authorities activate an emergency airspace regime known as Plan Kover, which translates as “Carpet”. It is a blunt instrument by design. Civil aircraft inside the designated area must leave it or land immediately, and airport operations can be restricted outright until the threat is declared over.

The logic is the same logic that governs every airspace closure anywhere: air defence radars and gunners cannot reliably tell a small, slow, low-flying drone from anything else in a crowded picture, and the systems being used to engage them are not precision instruments. Clearing the sky of airliners is not an overreaction. It is the only way to shoot at something without risking the wrong target.

Which brings us to the most uncomfortable detail of Sunday morning.

The Russian outlet Astra, working from witness photographs and video, suggested that one of the impacts at the Moscow Oil Refinery may have been caused by a Russian Pantsir air-defence system rather than by a Ukrainian drone. Astra also noted that a Pantsir battery was stationed some 500 metres from the logistics warehouse in Sofyino that burned the same night.

That claim has not been confirmed by Russian authorities, and it should be read as what it is: an inference from open-source imagery by an outlet the Kremlin has designated undesirable. But it is entirely plausible on its own terms. What goes up in a barrage of short-range air defence has to come down somewhere, and a city of thirteen million offers very few places for it to land harmlessly.

The claims, and the gap between them

Moscow's mayor, Sergey Sobyanin, gave the largest number and the loudest framing.

Russia's Defence Ministry gave a different figure for a different area: 1,110 Ukrainian drones shot down overnight into 20 September across Russian regions, annexed Crimea and the Black Sea. It did not say how many had been launched, which is the number that would actually tell you how the defence performed. Moscow region Governor Andrey Vorobyov reported 249 drones shot down or jammed across seventeen districts of his region alone, along with two dead and around twenty injured, three of them children.

None of these claims can be independently verified, and all of them come from the side being attacked. Treat them as the ceiling rather than the count.

From Kyiv, President Volodymyr Zelensky confirmed the strike and said Ukrainian forces had fired Flamingo cruise missiles alongside the drones, hitting the refinery, the Moscow-region warehouse and a facility in the Voronezh region. His comment on Russia's air defences was aimed squarely at the airports.

Fuel is the second-order problem

The Gazprom Neft Moscow Oil Refinery at Kapotnya is not a symbolic target. It is one of Russia's largest and the main fuel supplier for Moscow and the surrounding region, and the four airports that spent Sunday morning on restrictions all draw from the same regional fuel system. Damage to an airport's radar is a bad day; damage to the refinery that fills its bowsers is a bad quarter.

We covered the weapons side of this raid separately in Pelican Ballistic Missile Debuts in Ukraine’s Moscow Strike, including the debut of a Ukrainian system nobody outside Kyiv had heard of before that night. This piece is about what the same night cost the people in the departure lounges.

A war fought against timetables

There is a version of modern air power that does not involve fighters, and Russia is currently living in it. No enemy aircraft enters the airspace. No airliner is targeted. A few dozen cheap airframes fly toward a capital, the defensive procedure does exactly what it is written to do, and a national air transport network spends a day absorbing the consequences.

For the airlines, the cost is measured in crew duty hours, repositioning flights and aircraft parked where they should not be. For everyone else, the lesson is simpler and rather older than drones: an air defence system that works perfectly still closes your airports. That is not a failure of the system. That is the system.

BBC News on the drone strike that damaged the Moscow Oil Refinery, 20 September 2026.

Sources: aeroTELEGRAPH, Osprey, Meduza, Astra, the Russian Ministry of Defence, the Moscow Mayor’s Office, the Moscow Region administration, BBC News.