I work in the aviation sector, and I can tell you that for all intents and purposes Russian aviation has - at best - about three weeks before it’s show over.

One aspect is the fact that airspace available to Russian aircraft is very, very limited now. However, there is more:

Very few aircraft are actually owned by airlines, and instead most are owned by lessor companies, most of which are Irish. Under the sanctions regime, the view in the legal community is that those leases have to be terminated, otherwise Irish companies will be criminally liable.

More importantly: Russian operators are unable to effect insurances. Without those, no national aviation authority will allow access to its airspace. This would in effect mean the end of Russian operators flying internationally.

Furthermore, despite the presence of some Sukhois, Ilyushins and Antonovs, the bulk of aircraft operated in Russia is still Boeing and Airbus. Those use CFM, GE and Rolls Royce engines.

All these manufactures have cut off access to repair manuals without which the aircraft and engines cannot be serviced. They have also issued a global ban on servicing in other countries, so that Russian aircraft cannot be flown abroad for maintenance.

They have also stopped the supply of spare parts. From talking to our clients, I understand most airlines keep about a 2 or 3 weeks worth of spares supplies.

What does this mean? Russia will be in effect cut off from international travel, perhaps with the notable exception of China. It will be more isolated than the USSR, and even domestic journeys will be severely limited.

Sanctions - if drafted well - do work.

We can probably expect that some international operators will continue to operate some flights, perhaps to Istanbul or Dubai. But we’re talking about going from 100s of cross-border flights to perhaps 6 or 7. Why so few?

Europe is relatively unique in having an ‘open sky’. Provided an airline meets certain criteria, it can fly as many flights it wants within European airspace. Other countries don’t always have this, and the number of flights and airports pairs (routes) between them is regulated.

Unless, say, Turkey enters into an open sky agreement with Russia, which surely is unthinkable in the circumstances, the number of flights going to Turkey will be heavily suppressed by regulation.

It’s also worth noting that even if someone very clever managed to find a way - and I am sure there are plenty of fellow lawyers in law offices all over Russia thinking very hard about this - there is literally no way for Russian entities to make international payments.

They therefore won’t even be able to refuel or pay for airport charges. Even China would have to accept either a cash payment the yuans held by the Russian Central Bank or some form of extended credit, both of which are very unlikely.