Prosecutors say da Tonn's alleged victim - described by the District Attorney's Office as a 44-year-old female colleague who lives in Hong Kong - said she was attacked in a Brooklyn hotel room at 3am on New Year's Eve. Da Tonn was arrested soon after 7am.

The spokesman said the charges against da Tonn covered unconsensual oral sex and unconsensual sex.

A Cathay spokeswoman said that given the continuing investigation it was unable to provide any further comment.

'We must also respect the privacy of those involved. The company will co-operate fully with the law enforcement authorities in New York,' she said.

'The company takes the matter seriously and we are providing necessary and appropriate support and care to those impacted.'

Because the matter is subject to legal proceedings, neither the Aircrew Officers Association or the Cathay Pacific Airway's Flight Attendants' Union would comment.

The alleged assault is the latest PR headache for the airline.

In October, a captain was photographed sleeping in his seat at an altitude of 11,000 metres, prompting disciplinary proceedings against the picture taker. The airline insisted that a 'power nap' of a maximum of 40 minutes, while rarely used, was permitted on long-haul flights.

In August, photos of an air hostess performing oral sex on an expatriate pilot in a cockpit circulated on the internet. The incident cost both of them their jobs, although the plane was on the ground and out of service when the photos were taken.

Cathay's chief executive John Slosar said at the time: 'I find any behaviour that recklessly soils the company's reputation or our team members totally unacceptable.'

The scandal also led to the postponement of Cathay's multimillion-dollar international advertising campaign, featuring the tagline: 'Meet the team who go the extra mile to make you feel special.'

Some insiders feared the slogan would be subject to ridicule.

The campaign was launched two months later with the catchphrase: 'People. They make an airline.'