Air traffic across western and northern Europe may be back to 75% capacity following the volcanic ash cloud incident, which grounded planes for six days.
Thousands of travellers are still stranded abroad as airlines try to clear the backlog after flights resumed late on Monday.
Many are blaming those involved for bungling the scare and keeping planes grounded for too long, or simply just being over cautious.
Airlines estimate combined losses of £1.1bn ($1.7bn), according to the International Air Transport Association, equating to £260m ($400m) a day.
UK Transport Secretary Lord Adonis has already admitted the government were “too cautious” when taking the decision to ground flights.
