On the night of February 23rd the skies above Ukraine, and its border with Russia and Belarus, emptied. Ukrainian air-traffic control cancelled flights and closed the country’s airspace as Vladimir Putin, Russia’s president, went to war. The European Union Aviation Safety Agency warned airlines that there was a high risk to civilian flights and that Ukrainian airspace was now “an active conflict zone”.

That announcement, at around 12.45am GMT, caused aircraft to change course in mid-flight. An El Al plane heading from Tel Aviv to Toronto, which was over Chernivtsi, a city in western Ukraine, made an abrupt detour to leave Ukrainian airspace. Another aircraft, travelling from Warsaw to Kyiv, turned back to Poland.

In early February more than 400 planes, operated by over 35 airlines, travelled through Ukraine’s skies on a typical day. All must now be diverted. For a flight from Chisinau, the capital of Moldova, to Moscow, this increases the time in the air from less than two hours to more than three. By the early morning of February 24th there was just one flight into Ukraine: from the Dominican Republic to Kyiv which landed at around 2am GMT.

Even before the latest conflict, aircraft have avoided airspace over eastern Ukraine, after Malaysian Airlines flight MH17 was shot down in 2014. Two years later international criminal investigators concluded that it had been hit by a missile brought from Russian territory and fired from an area controlled by Russian-backed separatists. European security will be reshaped by Russia’s invasion of Ukraine. The continent’s eastern flight paths already have been. ■

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