What will be the Russian reaction?

Today’s downing of an SU-24 fighter bomber is the first serious loss suffered by Russia since it launched air strikes in support of Bashar Assad’s government nearly two months ago, 

It is a grim moment for the pilots, their families, and their comrades on the ground.

But it won’t have come as an immense shock to the Russian general staff, who know perfectly well that when you fly fast jets, and especially when you’re fighting an intensive air war, things can go wrong.

Whether from technical malfunction or enemy fire, the grim fact is Russia would have been incredibly lucky to get through this campaign without a single loss.

So, given that they must have known there was a strong chance of this, it is a safe bet that there are contingency plans in place.

Hence Russian army helicopters have already been seen scouring the area of the crash for the SU-24’s two crew members, in what is probably a well-drilled search and rescue procedure.

And at home, Russia’s tightly-controlled state media barely missed a beat.

Instead of playing down reports, or a suspicious pause before taking up coverage from elsewhere, Russian TV has been covering the incident in depth since it happened.

That suggests that the Kremlin was ready for the possibility of such an incident, and briefed TV chiefs accordingly to play it straight - conceding that in a war, one does inevitably take casualties.

The only question is, what do you do about Turkey.

Military retaliation is almost certainly out of the question. Turkey is a Nato member state, and shooting down its jets in response would risk starting world war three.

Instead, we may see air strikes against groups that Turkey supports on the ground - possibly including the Turkmen groups Ankara has already warned Russia against hitting.

There will also probably be a diplomatic response. Sergei Lavrov, the Russian foreign minister, has reportedly cancelled a planned trip to Turkey, and one Russian MP has even called for the evacuation of Russian tourists from the country.

How far that goes, however, is up to Vladimir Putin, and so far he is keeping his cards close to his chest.

His spokesman said earlier that the Kremlin would not make “some kind of statements until we have a complete picture".