My disabled 84-year-old mother was due to return to the UK on a Ryanair flight after visiting me in Germany. I had booked ­special assistance to help her on to the plane.

After I’d checked her in, assistance staff pushed her wheelchair to the departure gate and told her they would return to help her to her seat on the aircraft once boarding commenced.

That is as far as she got on her journey. Ryanair completed boarding and must have ignored all warnings that a passenger requiring assistance was missing because the flight departed with her luggage still onboard, including her diabetic medication. She was left stranded at the gate and I only managed to recover her from security several hours later.

We then had to spend the weekend trying to track down her luggage. My brother, meanwhile, had wasted a two-hour trip to Stansted to meet her.

I had to purchase a new ticket for her and accompany her back to the UK myself as my brother was by then away. I also had to hire a car at the other end.

Ryanair has refused to refund me for the missed flight or the consequent expenses, stating that special assistance is the responsibility of a third party. However, our contract was with Ryanair and the special assistance was part of the booking.

BD, Hamburg

This was a terribly distressing ­experience for your mother, who has hearing loss and was unable to hear the boarding announcements herself. It was only discovered that she was stranded when you returned to the airport after she called you and airport staff went in search of her.

It’s shocking that those staff did not clock a solitary elderly lady in a wheelchair when the gate had emptied, and it’s alarming from a security perspective that when she was marked as a no-show her baggage was allowed to fly unaccompanied.

My priority was to establish who should take responsibility when special assistance fails. To my surprise, Ryanair is correct, according to consumer lawyer Gary Rycroft.

“The airline is only responsible for special assistance whilst you are on the flight,” he says. “It is the airport who are responsible up to you getting on the aircraft and after you disembark, and the airline does not have contractual responsibility to supervise all aspects of it.”

You could, he says, make a legal claim against the airport, but since Hamburg is outside the jurisdiction of UK courts, this would be challenging. So I got in touch with Hamburg airport and ended up down a rabbit hole.

The airport blamed Ryanair, which, it said, was supposed to inform the special assistance team when boarding commenced but which had failed to do so. Boarding had been delayed by an hour.

“Hamburg airport unfortunately has no influence on the coordination between the airline and the ­service provider,” said a spokesperson helplessly.

Ryanair, on the other hand, insisted to me that special assistance teams should have picked up on the public announcements. As for the solo journey of your mother’s luggage, which Rycroft reckons is a breach of international law and the responsibility of the airline, Ryanair initially told you it had been removed from the flight, but admitted to me that it had not been.

This oversight has nothing to do with Ryanair, according to Ryanair. It was an error, it insisted, on the part of another third-party handler, AHS. AHS did not respond to my request for a comment about this, although it did confirm it was not responsible for special assistance.

My next port of call was Germany’s aviation regulator, the Federal Aviation Office. It told me that luggage could fly unaccompanied if required safety standards were met, but would not specify whether additional security checks have to be made to satisfy those standards.

So I’m afraid buck after buck has been passed and you are no further forward. All I can suggest is that you complain to the Federal Aviation Office about the breach of EU regulation 1107/2006, which gives passengers with disabilities a legal right to special assistance. You might also report the failure to remove the luggage of a no-show, which is in potential breach of EU regulation 300/2008.

Since baggage is the airline’s responsibility, you could, according to Rycroft, send Ryanair a letter before action detailing your mother’s consequent losses, then make a claim through the small claims court if they don’t stump up. To make a claim for damages for the special assistance failures, however, including the €400 you had to pay for replacement flights and hire car, you would have to make a claim through the courts – which, as I’ve said, is tricky, as the incident happened outside the UK.

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