An American Airlines pilot arrested at an airport security check-in after apparently arriving for duty drunk was found not guilty by a court yesterday after telling a jury that he must have consumed a third of a bottle of Irish whiskey in his sleep.

James Yates, 46, was found to be almost eight times over the legal limit to fly an aircraft shortly before he was scheduled to take the controls of a Boeing 767 carrying 181 passengers from Manchester Airport to Chicago in February last year.

The prosecution said that Mr Yates, an experienced pilot with the airline, had gone on a seven-hour drinking spree with his two co-pilots on the night before the long-haul flight.

In evidence, Mr Yates, a former National Guardsman who at one time was involved in policing the Iraqi nofly zone, said that he had woken up late on the morning of the flight. He claimed a sleeping disorder may have led to him drinking from a bottle of Bush-mills the night before.

He insisted that he had not intended to carry out his duties as the flight’s first officer that morning, but was turning up at the airport simply to inform his captain that he was unfit to fly.

At the end of a three-day trial, the jury at Minshull Street Crown Court, Manchester, took only 90 minutes to clear Mr Yates of a single charge of carrying out an activity ancillary to an aviation function while over the drink limit. He slapped colleagues on the back and grinned with delight when the verdict was announced.

Earlier, the jury was told that he had left the Renaissance Hotel in Manchester for a seven-hour drinking session with his two fellow pilots. He had drunk pints in at least four pubs before retiring for a Scotch in the hotel bar.

Around midnight, he swallowed a sedative to help him to sleep. When he woke up the next morning, after 9am, he could hear his captain banging on the hotel door. He noticed that about a third of the Irish whiskey he had bought the previous day had been consumed, but he had no memory of drinking it.

He said that, in the past, his ex-wife, mother and fiancée had noticed he was capable of doing “strange things” in the middle of the night. Once he had gone to bed, only to wake up in front of the television.

In evidence, he said that after the taxi driver taking him to the airport had scolded him for his drunkeness he realised he was not in a fit state to carry out his duties. At the airport, a breathalyser test revealed he had 71 micrograms of alcohol per 100 millilitres of breath; almost eight times over the 9 micrograms limit. Three hours later, a blood test gave a reading of 129 milligrams of alcohol per 100 millilitres of blood; more than six times the legal limit.

During the trial, senior American Airlines executives gave evidence in Mr Yates’s defence. When the prosecution told Captain John Burton III, the airline’s chief pilot, that Mr Yates was not sick, but was, in fact, drunk, he replied: “I would consider that sick.”

Brigadier-General Thomas Botchie, a senior commander in the Ohio National Guard, told the court he had known Mr Yates since they were both fighter pilots in the 1980s. “I consider James to be a professional prepared to come to the defence of his country,” he said in a written statement. “It takes a certain calibre of person to qualify. I have always found him to be a person of high morals and trustworthy. My opinion is, if James says he’s telling the truth, he’s telling the truth.”

Mr Yates, of Columbus, Ohio, may yet face internal disciplinary action.

A spokesman for American Airlines, based in Chicago, said: “We are pleased that the full details of the case have now been heard and that the jury have found James Yates was not guilty of the charges brought. He continues to be on a leave of absence from the company and upon his return from that leave the company will discuss with him his continued employment. These are private discussions and we will not comment further on the outcome. Our primary concern has and always will be for the safety of our passengers and crews”.

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