A woman is said have thrown $9,500 in cash at a man on an airport runway after they were escorted off a plane.
The flight had to be diverted after the couple had a fierce argument, resulting in a man being taped to his seat, passengers said.
The airline, Eva Air, confirmed the trouble began about five hours into the 9.35pm flight from Heathrow to Bangkok on September 30 when a woman moved to premium economy without paying for the upgrade.
A passenger said the couple had a blazing row and the pilot told passengers for safety he would have to turn back and land in Vienna, Austria, which would take an extra two and a half hours.
Videos showed police escorting the pair off of the flight, but then on the runway she appears to throw cash at him.
Notes fly in the air and land all over tarmac before the male and airport workers start picking it up.
Andy Singh, 63, a grandfather who was travelling on the flight to Thailand for a month-long holiday, alleged the woman and man were already intoxicated.
“They kept talking about money, he would say ‘she’s got my £5,000 in her bag’.
“The captain said ‘we have to go back to Vienna because [of] staff safety and the passengers’ safety, ladies and gentleman we have got no choice but to get back to Vienna’.
“He said ‘it will take two and a half hours to get back there, and we will decide what to do after that.’”
On landing, the couple were escorted off the plane by the police.
Footage shows the man, wearing a light coloured tracksuit and carrying a neck pillow, scowling at Mr Singh for recording.
Mr Singh said: “The police took the lady first. He decided after a couple of minutes on the tarmac to grab the bag from the lady, but the lady just threw all £5,000.”
Both were put in a police van, and footage shows an officer trying to pick up some of the strewn cash.
“Some of the notes, they were floating away because nobody picked them up, they only picked up the nearest ones,” Mr Singh said.
He said all of the passengers were put up in a hotel and due to set off again at 5.30pm on Sunday, Vienna time.
Eva Air said five hours into the flight from London “a female passenger moved her seat from Economy Class to Premium Economy Class and refused to pay for the upgrade cost”.
“Another male passenger travelling with her also engaged in disorderly behaviour and smoked an e-cigarette adjacent to the cabin galley,” the airline said.
“Our flight attendants took quick action to stop these passengers but encountered inappropriate insults and physical abuse.
“After seeking the assistance from eight other passengers, these two unruly passengers were successfully restrained.’’
Mr Singh said a group of male passengers restrained the man by taping him to his seat.
He said: “Black tape, two inch wide tape, they had that around him on the seat – three hours he was tied to the chair.
“The actual help was done by the passengers, they put him in the chair and put the tape around him.
“Seven or eight big people.’’