THIS IS ONE expensive bender.

Robert Coppack was ordered by a federal judge yesterday to shell out more than $53,000, after his drunken antics - which included groping a flight attendant - forced a London-bound flight to return to Philly in May.

Coppack, 41, must also serve a five-month sentence in community confinement for the incident, to which he pleaded guilty in September, according to Patty Hartman, a spokeswoman for the U.S. Attorney's Office.

The trouble began when the California resident boarded the US Airways flight after getting drunk on vodka, according to an affidavit filed in U.S. District Court.

Two women sitting next to Coppack told flight attendants that he "touched both inappropriately," the affidavit states.

An attendant reprimanded Coppack, but he became more vulgar and aggressive. When the attendant sent him to the back of the plane, Coppack touched another woman's arm and breast on his way, the document says.

Apparently he didn't stop there: When air marshals met Coppack at the back of the plane, officials said, the drunken man threatened to assault them if they didn't leave him alone. With that, the marshals cuffed him, ending the apparently vodka-fueled episode.

Coppack, who holds dual-citizenship in the United Kingdom, was charged with intimidation of a flight-crew member or attendant and interfering with the duties of a crew member or attendant, to which he pleaded guilty Sept. 17, court records show.

As part of his sentencing, he must submit to regular drug and alcohol screening and attend mental-health treatment while on supervised release, Hartman said.

On Twitter: @Vellastrations