In defence of the volcano
The closure of much of Europe's airspace is beginning to bite in many ways.
TUI Travel, the leading holiday travel group which owns Thomson and First Choice, has become the first company to estimate the losses it is incurring from the grounding of flights. Up to yesterday, it says the costs have been £20m - and that the daily expense is between £5m and £6m.
You'll find it increasingly difficult to buy roses, since most of them this time of year are flown from Kenya.
And you may find, like the family Peston, that your kids are being given the day off school, because substantial numbers of teachers can't get home from their holidays.
But it is time that someone defended the battered reputation of the erupting Icelandic volcano.
Because all reports to the contrary, it isn't the volcano that has grounded our aircraft; it's the weather that has done the damage.
Or at least that's the view of the airline bosses to whom I've been speaking.
They point out that there are other live volcanoes in the world. But when they belch out ash, they don't bring air transport to a standstill.
The airlines tell me they are quite habituated to flying round ash clouds.
So why is this cloud apparently so much bigger and more dangerous?
Well it's because of the unusual weather conditions that are causing it to spread over some of the busiest flying lanes in the world.
Also, and here's what may tickle a few of you, the official view of the extent and location of the cloud, its geography, is a computer simulation by the Met Office.
Airline executives can't resist telling me that this is the same Met Office which last year told us to prepare for that blistering BBQ summer which turned out to be something rather cold and damp.
Now the accuracy of the Met's ash map is being improved by hard data gathered by observation planes.
But it seems highly unlikely that it can ever be 100% accurate.
Which is why the airlines are desperate to find some other fundamental solution that would give them - and their passengers - confidence that the closure of airspace is a one-off event.
Whether that's fitting special filters to engines or developing a contingency for low-level flying, what they say they need is some system that will reassure customers that any reopening of airspace won't be temporary.
As I've repeatedly mentioned, most airlines are only just recovering from the worst recession in their history.
They're therefore deeply alarmed at the very real possibility that many people will simply choose not to fly either for business or leisure, if there's a risk that they could find themselves trapped abroad by a renewed grounding of aircraft.
Any significant dent to the recovery in passenger numbers could undermine the confidence of some airlines' creditors and precipitate a new spate of bankruptcies.