"The UK Civil Aviation Authority considers that where an aircraft type is grounded it would be an extraordinary circumstance under Regulation 261/2004. 

"Airlines will still be required to provide care and assistance to consumers, and to reroute them to their final destination if the consumer still wishes to travel but will not be required to financially compensate them.

"Airlines will also be required to demonstrate that they took all reasonable measures to avoid cancellations and will need to consider alternative arrangements, for instance leasing other aircraft".

Your rights when there is a problem with your flight: Leaflet that sets out passenger rights for any flight departing from an EU airport and flights arriving at an EU airport and operated by an EU airline.