Under-fire United Airlines has been forced to admit a "horrible failure" which saw a woman allowed to get on the wrong flight in a 28 hour ordeal.
Lucie Bahetoukilae, who speaks no English, thought she was getting on a flight to Paris from Newark, Daily Mail reports.
But she was horrified when she ended up in San Francisco.
After getting onboard the plane, she even showed her boarding pass to a member of the crew after finding someone in the seat she thought was hers.
Instead of spotting the error and helping Bahetoukilae find the correct aircraft, the crew member instead directed her to another seat on the same flight.
She was unaware that United had changed the gate number, and she said no announcements were made in French, and she was not emailed, ABC reports.
The airline has now settled a confidential lawsuit.
Her niece, Diane Miantsoko told the network: "If they would have made the announcement in French, she would she have moved gates. Of course, because she speaks French she would've moved to another gate."
After traveling 5000km in the wrong direction, Bahetoukilae had to wait for 11 hours in San Francisco before she could be put on a flight which would take her to France.
Miantsoko said: "They didn't pay attention. My aunt could have been anyone. She could have been a terrorist and killed people on that flight, and they didn't know they didn't catch it."
United awarded the passenger a refund - although she had not asked for one - and given her a voucher for another journey. The company said it is taking steps to ensure it does not happen again.
The embarrassment comes weeks after footage of passenger Dr David Dao being dragged off a plane in Chicago sent shockwaves across the world.
United chief executive Oscar Munoz later told a committee of the House of Representatives it was a "mistake of epic proportions".
On April 19, the company had further negative publicity following the death of a giant rabbit, named Simon, in the cabin hold of a flight from London.
It was forced to pay a five-figure sum in compensation following the animal's death.