Were the ash cancellations really necessary?

As volcanic ash continues to drift across Europe, sporadically closing airports, airline bosses are asking whether the mass cancellation of flights we saw initially was ever really necessary.

In the past, eruptions at the Eyjafjallajokull glacier have presaged more serious eruptions at its bigger neighbour, Katla. There is a chance, then, that this could happen again.

Rajan Datar finds out what the travel industry has learned for next time.

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