I agree that a one minute flight through an erupting volcanic plume will destroy an aircraft.
My point is being lost.
This is not a proximate volcanic plume. It is an enormously dispersed cloud.
The Icelandic volcano that disrupted Europe was a 4 hour flight away from AMS/FRA/CPH/LHR etc. (I know because I have flown from continental Europe to Iceland in a 747 many times.) That would be the equivalent of having Chile, in this example, in the same location as Perth......
This ash cloud (for want of a better word) has come more than half way round the world..... It didn't even come the short route (i.e. South America to Australia/New Zealand) it came the long way round. This ash cloud has travelled from South America, via the South Atlantic to South Africa. Then onwards across the Indian Ocean to Australia. It is preposterous to think it still has the same density of pumice material as the other volcanoes that have disrupted air travel.
All the aircraft operating manuals being quoted are irrelevant. I'm saying - the Emperor Has No Clothes. I suspect there is no ash cloud.