Posted this in another thread not long ago.
I think a lot of airmail systems are paralysed with international flights at less then 10%. A good percentage of the air cans in every plane from one country to another are usually what carries mail from one country to another.
Basically there is not enough cargo planes in the world to make up the loss.
Know planes are getting converted as I type by many airline companies as no money in having planes sitting or flying them with a top deck of empty seats
Most national post systems have a contract with their national carrier for post/parcel transport in aircans like in the picture below
so several of these in ever plane from one country to another are not being delivered daily like in normal times.
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