Today's ruling against budget airline Ryanair brings a clearer understanding of airlines responsibility towards their passengers.
The ruling is called EU 261, and it asserts firmer and far-reaching rights for passengers.
The ruling has been condemned by Ryanair, who say it will increase ticket prices.
The ruling does not concern compensation - but reimbursement of expenses incurred during an incident like the ash cloud.
If your flight was cancelled due to the volcanic ash cloud in 2010, today's ruling means you were entitled to reimbursement of 'reasonable' expenses.
However, most payments of this kind have already been made (including by Ryanair) - the court decison was a "test case" to settle how the law should be interpreted for future situations - including snow, strikes and the like.
The airline is liable for the following:
- Some communications
To claim compensation, passengers should contact the airline company directly.
The Civil Aviation Authority says customers have a number of rights they may not be aware of, and advises how to exercise them.
- Rights to a refund or another flight
- Rights to care and help at the airport
- Extra help for vulnerable passengers
- Package holidays
Rights to a refund or another flight
- If your flight has been cancelled, your airline must get you to your destination or offer you a full refund.
- If your flight is delayed by more than 5 hours and you no longer want to travel, you are entitled to a full refund.
- If you are a transfer passenger you are entitled to a flight back to your original departure point.
- Be aware: if you accept a refund your airline no longer has to look after you.
- If the disruption is severe, your airline may advise you to make your own travel arrangements and will reimburse costs. If this happens: make a note of the conversation and any guidance, ask the airline to update your booking with details of the agreement.
Rights to care and help at the airport
If your flight has been cancelled or delayed for several hours, your airline must look after you, after a certain period of time:
- 0-1,500km: Your airline must assist you after two hours.
- 1,500-3,500km: Your airline must assist you after three hours.
- 3,500 +: Your airline must assist you after four hours.
After these times your airline is obliged to provide food, drinks, and some communications. If you are delayed overnight, this means a hotel and travel to and from the hotel to the airport.
If the airline does not pay for refreshments you can pay for your own and claim money back: be aware this will not include alcohol and you must hold on to receipts.
Extra help for vulnerable passengers
- Airlines must look after passengers with a disability and unaccompanied children as a priority
- If you have booked a package holiday, your tour operator is responsible for rearranging your flight.
- If you holiday cannot be rearranged or is significantly changed you are entitled to a refund of the full package price if you wish.
A spokesman for the Civil Aviation Authority said: