Now that the dust has settled (deliberate pun!) the fingers are being pointed, and many of them to the CAA and the British Government. In short the allegations are that it took 6 days for the CAA to turn round and say that in actual fact the aircraft manufacturers and engine manufactures have declared that aircraft can operate quite safely in far worse conditions than was the case with the skies over the UK.
What is becoming increasingly evident is that everyone was dragging their heels, no one would make a deciosn, for fear of recriminations if it were the wrong decision. It took British Airways to force their hand by electing to fly 24 long haul flights back to the UK so as to arrive Tuesday evening. Some of those aircraft were forced to divert to Shannon, but some held for 3 hours waiting for Heathrow to open up. Purely by chance as the aircraft were in the holding pattern the announcement came that UK airspace and airports would be opened in an hours time!
Only after the event has the amount of ash in the atmosphere actually been revealed....and we are now told the aircraft can operate perfectly safely in levels of ash 20 times more dense than that which occured over the UK. So have the manufacturers just come up with this figure...of course not...engines have to operate in all sorts of contaminated environments, including volcanic ash (take a flight into Catania which is next to Mount Etna....you'll regularly fly through and physically see the ash), high level sand/dust from the Sahara and sand storms on the ground. The manufacturers know the precise tolerances that their engines can operate to. So it all goes back to the UK authorities over reacting.....think back to Bird Flu if you want another classic example!
Now the airlines are being asked to compensate all the passengers in accordance with EU regulations....which were put in place by the Governments who forced the grounding of the aircraft in the first place. If the airlines paid up what is being expected I would suspect many would just go out of business*. Someone has to pay, but it has to be the respective Governments, not the airlines.
* a quick example...an airline with just one aircraft with 150 seats that should have operated say 10 flights over the 6 days....typical repatriation cost say £1,000 per passenger x 150 x 10 = £1,500,000. Thats more than they could possibly make in profit over a 12 month period. Factor this by 10 for a 10 aircraft operation, by 100 for a 100 aircraft operation....you get the picture!