The Van Der Lans v KLM court case: Five things you need know

What's the case all about?

The European flight delay Regulation EC 261/2004 entitles air passengers held up by three hours or more to up to €600 (£435), as long as the delay was not caused by "extraordinary circumstances". But the regulation does not give a definition of "extraordinary circumstances", something the airlines keep quibbling about. Corina van der Lans' KLM flight from Quito in Ecuador to Amsterdam was delayed for 29 hours due to the discovery of defective components in the plane. KLM turned down her request for compensation so she took the airline to court.

What was KLM's argument?

The case was heard at the European Court of Justice (ECJ) in May but the court only made a decision on Thursday. KLM had tried to argue that "spontaneous" technical issues (as opposed to technical issues discovered during routine maintenance) are an "extraordinary circumstance". But the ECJ ruled that all technical faults are inherent in the normal exercise of an air carrier's activity.

It's not the first case of its kind, is it?

No, there have been several others over the past decade as airlines try to avoid compensating passengers for delays.

The most recent big case was Huzar v Jet2.com in October 2014 when the UK Supreme Court held that technical problems are not extraordinary circumstances.

Is the ruling good news for passengers?

Yes. The result will have a big impact on when passengers can claim compensation for flight delays. Because the ECJ is a higher authority than the Supreme Court, the vast majority of compensation claims due to technical issues would have been turned down if KLM had won.

What do the experts say?

Kevin Clarke is a lawyer at Bott & Co, which acted on behalf of Ronald Huzar. He said: "That the same issue has had to go to the ECJ despite the Supreme Court ruling shows the lengths to which the airline industry will go to avoid paying out on valid claims. Fortunately, the courts have ruled in favour of consumers."