I love the way everybody jumps onto the engine damage bandwagon whilst totally ignoring the dangers involved with the total blockage of the pitot static system. Especially after the Air France event that could have been caused by a similar situation albeit rapid ice blockage. I admit fully that damage to the engines is extremely concerning the other dangers are no less worrying!
Now that is a possible failure mode that IS analogous to flying in dust/sand storms. Not much evidence of pitot blockage in these conditions - especially as none of the 'lets fly' brigade here are envisaging flying in heavily contaminated areas. I've seen more dust on my mantlepiece than in the channel skies this weekend.
I did once get an ice warning at 39o centigrade, which turned out to be an insect of some kind hitting the probe, but I don't think the ash will do anything similar.
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