A United passenger fought with his girlfriend, threatened to ‘mess up the plane,’ and forced a diversion. Now he must pay $20,000.

• Alexander MacDonald was asked to calm down after arguing with his girlfriend on a United flight.
• He then threatened a flight attendant and the plane diverted to Bangor, Maine.
• A judge has ordered him to pay the carrier $20,638, and he’s set to be deported to the UK.

A United Airlines passenger has been ordered to pay the carrier more than $20,000 after forcing a flight to divert.

Alexander MacDonald, a 30-year-old from England, pleaded guilty to one count of flight interference related to the March 1 incident.

He was flying from London to Newark when he started arguing with his girlfriend, according to an affidavit seen by Business Insider.

It adds that the flight purser asked MacDonald to lower his voice and he initially did calm down. But then they found him “yelling” at another crew member in the plane’s back galley, per the court document.

The affidavit says MacDonald asked the purser if they would like to “have a problem,” threatened to “mess up the plane,” and backed them into the corner by putting his hands on their shoulders.

The flight crew and two passengers eventually managed to restrain MacDonald with flex cuffs, but he continued to be verbally and physically aggressive, the affidavit says.

The captain then decided to divert the plane, which had 160 passengers on board, to Bangor International Airport in Maine.

Last Thursday, a judge in the US District Court of Maine remanded MacDonald to custody to be deported back to the UK.

He was also ordered to pay $20,738, of which $20,638 is restitution to United Airlines.

United declined to comment when contacted by Business Insider.

In January, a British university student avoided paying the Spanish Defense Ministry $120,000 after he joked about blowing up a plane and fighter jets were scrambled. He was found not guilty of a charge of public disorder.

The number of unruly passenger incidents rose sharply as aviation returned from COVID disruption in 2021 and has yet to return to pre-pandemic levels.

Incidents have been steadily declining, but last year saw around double the number of incidents that occurred in 2020. With 598 reports as of April 21, this year looks set to be around 80% higher than pre-pandemic levels.