Ryanair has been thwarted in its bid to limit how long passengers have to claim compensation for flight delays.

In the test case decision of Goel & Trivedi v Ryanair, a judge at Manchester County Court this week ruled that passengers in England and Wales have six years to take a flight delay claim to court.

Ryanair had tried to argue that that as passengers signed up to the company's terms and conditions, they waived their right to the EU-wide six year limitation period and could reduce it to two years.

Stopped in its tracks: Ryanair has been thwarted in its bid to limit how long passengers have to claim compensation for flight delays

Lawyers at Bott & Co Solicitors estimate the test case decision could open the floodgates to 2.66million Ryanair passengers claiming around £610million in compensation, with claims against other airlines likely to follow.

The test case was brought by six passengers in two families who suffered a near ten hour delay when returning to Britain on a Ryanair flight from Reus Spain to Stansted in 2008.

Lawyers for Archana Goel, in a party of two, and Diwarkar Trivedi in a party of four, said the judge’s decision ‘stands to benefit millions of passengers'.

Kevin Clarke, of Bott & Co, said: 'We're delighted that the court has dismissed yet another argument put forward by the airlines to restrict passenger rights.

'The last twelve months have seen a series of landmark judgments obtained by Bott & Co on behalf of millions of passengers and this is as important as any of those that precede it.

'The Supreme Court decision last year said passengers have six years to bring a claim. That is a definitive, binding, clear judgment from the highest court in England and Wales.

'This should have concluded matters but unfortunately Ryanair have been able to tweak the argument; we found ourselves running a complicated court case arguing the fine points of contract law.

'We fully expect the airlines to continue to fight these cases but we are prepared to hold them to account in each and every instance where the law says compensation is payable, and with the courts continuing to find on behalf of consumers we've real cause to be optimistic that passengers will receive the compensation they are entitled to.'

Statement: In a statement, Ryanair said: 'We note this ruling which reverses Lower Court orders that a two-year time limit for claims is reasonable.' Ryanair boss Michael O'Leary is pictured

In a statement, Ryanair said: 'We note this ruling which reverses Lower Court orders that a two-year time limit for claims is reasonable.

'Since we believe a six-year time limit for submitting such claims is both unnecessary and unreasonable, we have instructed our lawyers to immediately appeal this ruling.'

In his decision Judge Platts said that Ryanair’s legal argument 'requires a somewhat ingenious legal analysis which I doubt was in the mind of the parties when the contract was made.'

How do I claim for a delayed flight?

The first thing to bear in mind is that the airline must, according to the Civil Aviation Authority, 'take care of you and get you to your destination'.

You can also choose not to travel, and get a refund of your ticket cost if the delay lasts for five hours or more but the flight is not cancelled.

If your flight is delayed for three hours or more and you still decide to fly you should contact the airline directly in writing. Most have set complaints procedures contained in standard complaints forms.

If no standard complaints procedure is in place, it may be best to make initial contact by email or letter. Always keep a copy for your records.

Complaints: If your flight is delayed write a letter or email to the airline directly and include full details of what you are claiming

Make sure you include full details of the the nature of the include. The CAA recommends including details of what happened, when and why you feel you are entitled to receive a payment.

Clearly state exactly how much compensation and what expenses you are claiming for. Making wild estimates as to how much you think you should be entitled to will get you nowhere.

On its website, the CAA has a standard letter as a guide when writing a claims letter.

Before you claim, you need to do your homework and check that your claim is valid under EU laws regarding the length of the delay, journey time and airport destination base.

How long do I have to make a claim?

As interpreted by the judge in Goel & Trivedi v Ryanair, EU law gives passengers six years to make a claim for delayed flight compensation.

Last year, the Supreme Court ruled that delayed passengers in England and Wales have six years to claim, but Ryanair says passengers who book with it accept their terms and conditions, and therefore the claim limit is two years.

This argument has been rejected in a test case decision likely to be flowed in similar future rulings.

How much compensation can I get?

In reality, not as much as you think you are entitled to. Under EU law, passengers can claim for a flight delay if they reach their final destination three hours or more after the scheduled arrival time and can be entitled to up to £440 per passenger.

The flight you are claiming for must have departed from an EU country on an EU airline. The level of compensation payable is a fixed amount based on the flight distance and length of delay and is supposed to compensate for loss of time and inconvenience, rather than the cost of a ticket.

As a guide, for a flight up to 1,500km (London to Paris) and a delay of three hours or more, the most you will receive is £180.

Measly: For flights over 3,500km (London to New York) long delayed for over four hours, the most you will receive in compensation is £440

For a flight over 3,500km (London to Algiers) long and a three- to four hour delay, compensation rises to £220.

For flights over 3,500km (London to New York) long delayed for over four hours, the most you will receive in compensation is £440.

You won't be entitled to compensation if the delay was due to 'extraordinary circumstances' such as severe weather. But the courts have ruled that a mechanical breakdown is not an 'extraordinary circumstance.'

The airline could take quite some time to give you a response, but if you are successful in your claim, you could get a cheque along with the decision letter.

What can I do if I am unhappy with the airlines' decision?

If the airline does not find in your favour the complaint can be escalated with the help of the CAA.

The CAA will be able to help you if your flight is covered by EU law and have a standard online system to submit details of your complaint.

You can also call the CAA's advice and complaints team on 020 7453 6888 to discuss the complaint and whether there might be another way to resolve it.

If the CAA can't help you get anywhere with your claim, you could consider taking legal action against the airline. This is likely to be costly, time consuming and stressful.