This volcanic ash is really a form of sand?
In the Middle East, there is sand in the air all the time. When the QR A319 arrived in ARN, I was always able to scoop out an egg cup full of sand from the back of the engine. The ME carriers must ingest sand all the time. So if this is the same sort of sand as volcanic ash, how much is in the atmosphere in the Gulf, and how much in the atmosphere over Europe?
Are we talking the same sort of concentration, or is the density much greater?
If the numbers are similar, I don't see a problem.
perhaps Rolls Royce knows..