Shorter delays of three hours or more experienced by short-haul passengers could mean they are entitled to €250 in compensation. Alex Neill, Which? managing director of home products and services, said: “Some airlines seem to be making it as difficult as possible for passengers to receive the money that they are rightly entitled to for flight delays.”The consumer group is calling for a transport ombudsman who can enforce compensation for travellers. It said many of the cases in which airlines refused to pay were down to differing interpretations of the law. The CAA believes that passengers on a multi-leg trip should get compensation if they miss a later flight because their first flight was delayed.But some airlines, including Emirates, argue that if the second leg did not start or end in the EU, they are not liable to pay out – even if it was their delay which causes the passenger to miss the second flight. Earlier this year the CAA announced that it would be taking enforcement action against five airlines, including Emirates, for not giving passengers compensation for delayed flights. Two cases brought by passengers who were denied compensation by the airline are also due to be heard by the Court of Appeal at the end of next month. Airlines are wrongly withholding compensation from delayed passengers, research has found. Analysis by consumer group Which? of Civil Aviation Authority data found that in 53 per cent of cases the airline was told to pay up after having refused a passenger compensation after their flight had been delayed. The worst offender was Norwegian Air, which was told to pay out in 83 per cent of cases where a passenger had complained to the regulator about not being compensated for a delay. The CAA said Ryanair was in the wrong in 77 per cent of cases and the Spanish airline Vueling was ruled against 79 per cent of the time. Because the CAA cannot enforce its decisions, the data also shows that many airlines decided not to follow its recommendations.In 74 per cent of cases where it was told it should pay up, Emirates declined to do so. United Airlines also said it would not pay in 42 per cent of cases. Under EU law passengers flying long-haul can be entitled to up to €300 in compensation if their plane is between three and four hours late, or €600 if the flight arrives behind schedule by more than four hours. Emirates called the CAA’s stance “misleading and unprofessional”, and said: “The safety of our passengers and crew always comes first, and many flight delays are caused by factors that are beyond our control and which are not the airline’s responsibility – such as inclement weather, bird strikes, and airport closures. “We do everything possible to ensure that any disruption caused to our passengers is minimised.” A Norwegian Air spokesman said: “We understand that punctuality is vital for our passengers, and we strive to operate all flights on schedule. “We take customer care very seriously and we always maintain a consistent policy regarding delays and cancellations in accordance with EU261”.A Vueling spokesman said: “Due to the busy period of the summer season and operational disruptions experienced by Vueling in early July 2016, it took the company longer than usual to reply some of our customers’ claims. “These claims have already been managed by the company and the payment of compensation to passengers was done fully complying with our obligations under the EU 261/2004 regulation.”A CAA spokesman said: “Last year we introduced alternative dispute resolution to the aviation industry so passengers who have been unable to resolve a complaint with an airline can get an independent decision that the airline must abide by.”The vast majority of UK airlines already offer passengers access to these services and, in total, nearly 80 per cent of passenger journeys from the UK are now covered by airlines who are signed up to dispute resolution services.” Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.