We are talking about invisible ash Ie not in cloud or mist form.
Take the fact that No One has lost their lives due to Volcanic ash in more than 50 years and you have to question an overreaction.
As a pilot I take the view that if I cannot see it there is no threat!
Threat to me is something which will endanger my flight Ie stop my engines!
Ash which is of such low density that it is not visible will not stop or fail an engine!
Long term there may or may not be a shortening of the egine life but that is a financial decision not a safety decision.
I repeat there has NOT been a fatality due to ash in over 50 years of aviation.
The same cannot be said for Bird strikes or thunderstorm incursions,
Double standards ?
There is proven risk and perceived risk. Birds and thunderstorms are proven risk with a track record.
Invisible ash has no track record and is perceived unproven risk.
If we are so safety aware why not close masses of airspace in the bird migration season or ground aircraft when there is thunderstorm activity?
The billowing ash clouds are a different matter. They are as visible as a large CB but invisible ash ? Come on ! Press hype and liability fear based on nothing.
long term and engine life a vague maybe but a financial decision not a safety one.