Beware: Don't drink three glasses of wine and take the prescription sleeping pill Zaleplon, especially at 37,000 feet over the Atlantic Ocean.

Sarah E. Buffett, an immigration and corporate lawyer in Charlotte, N.C., did just that on a trans-Atlantic US Airways flight from Charlotte to London Heathrow Airport early Wednesday.

Halfway across the Atlantic, Buffett became verbally threatening and physically aggressive toward a flight attendant, and tried to damage her seat in the first-class cabin and the area immediately around her seat, according to a federal affidavit. She also took an entertainment-system remote and attempted to smash an aircraft window.

Buffett had to be physically restrained by flight attendants and passengers. The pilot turned the plane around and diverted the flight to Philadelphia. The flight tracking website flightaware.com said US Airways Flight 732 had reached Cape Breton Island, Nova Scotia, Canada, when it turned back.

The Airbus A330-300 plane was met at 4:45 a.m. by Philadelphia and Tinicum Township police.

Buffett, 41, was escorted off and charged by the U.S. Attorney in Philadelphia with intimidation of a flight crew member and related federal offenses.

At an arraignment Wednesday afternoon, U.S. Magistrate Judge Jacob P. Hart released Buffett on her own recognizance, conditional on surrendering her passport and not traveling on a commercial airline until the disposition of the criminal charges.

When the defendant told the judge she did not remember what happened, he asked a federal public defender in the courtroom to step in and advise her.

Buffett, a partner in a Charlotte law firm where her focus is international, corporate and immigration law, told federal investigators that she had drunk "at least three glasses of wine" and had taken a Zaleplon prescription pill, which had been prescribed for insomnia.

She said she recalled telling the flight attendant not to serve her dinner, "and from this point forward, she did not remember the incident," FBI Special Agent Walter Szpak and Homeland Security Investigations Special Agent Brian Jones said in the affidavit.

"Her next memory was of being physically restrained by an unknown male and then the flight's diversion to Philadelphia," according to the affidavit.

For the 267 passengers on board, it was a long night. Flight 732 was scheduled to leave Charlotte at 10:30 p.m. Tuesday, but did not get off the ground until around midnight.

When the plane landed in Philadelphia on Wednesday morning, the passengers were told their flight was now canceled and they would be rebooked on other departing flights to London.

The reason was the original crew members would soon "time out," or exceed the number of hours they could work in a shift.

"I've been up for 32 hours trying to get to London," said passenger Carly Sergent, who was on a honeymoon with her husband, Ken Piel.

The couple got rebooked on an 8:45 p.m. flight leaving Philadelphia on Wednesday. "We've got our fingers crossed that it's all going to work out this time," she said, waiting at Philadelphia airport.

"It just inconvenienced everybody - 200-plus people were completely inconvenienced," Sergent said. "One woman was going to her sister's funeral. A bunch of people were going on cruises of a lifetime, and they were going to miss their connections.

"What we came away with was how one person can go on a plane, take this medication, and ruin over 200 people's trips," she said.

215-854-2831@LoydLinda