A drunken mother revealed her G-string on a flight to Heathrow Airport and allowed a fellow passenger to fondle her, Isleworth Crown Court has heard.
Clare Irby, a member of the Guinness brewing dynasty, was flying from Bangalore on Kingfisher Airlines on 26 March when the incident occurred.
Captain Vivek Sondhi told jurors Ms Irby, who was with her son, aged two, was "on the verge of being dangerous".
Ms Irby, 30, of Fulham, west London, denies being drunk on an aircraft.
She told the court that she had drunk "maybe four or five" glasses of red wine on the flight but was only "tipsy".
Fondling denial
She said: "I was still fully functioning with all my faculties. I wasn't drunk."
Ms Irby said she spoke to fellow passenger, Daniel Melia, but said: "I can assure you no-one touched my breasts."
She denied there was any issue with the way she changed her clothes on the flight, saying she took care to protect her dignity.
However she admitted talking loudly, saying that her son "doesn't listen to me if I whisper".
Ms Irby criticised the flight attendants and said: "I didn't feel that they were particularly pleased by having a single parent and child, for some reason."
The court heard that when police described Ms Irby's alleged behaviour, she told them: "It sounds like I'm hearing about a stranger."
However Polly O'Callaghan, another passenger on the flight, alleged that Ms Irby had been acting flirtatiously with Mr Melia.
Ms Irby and Mr Melia, 36, had drunk several glasses of wine together, the court was told.
Ms O'Callaghan said she heard Ms Irby say: "I'm not normally this relaxed. It's just all the opium I've been taking."
She added that the comment may have been made in jest.
She said the pair were loud and abusive, claiming they regularly pressed the attendant call button.
It was further alleged that Mr Melia's girlfriend moved away from him because she was being ignored.
Child concerns
Ms O'Callaghan said she also had concerns for Ms Irby's son, who was jumping up and down on a seat while Ms Irby slept.
She also said Ms Irby put her hand into the face of a female flight attendant, while swearing at another one.
Describing Ms Irby and Mr Melia's behaviour, Mr Sondhi said: "They were on the verge of being dangerous, I would say, so I asked my flight director to stop serving them any more liquor.
"They were kind of sprawled in the seats. They were slurring and the man was a little more aggressive in his behaviour."
Meanwhile, flight attendant Shivaneji Sharma said that Ms Irby took off her skirt, revealing her G-string, before changing into a pair of leggings.
Another flight attendant, Arpita Mehra, said: "She was busy with the guest sitting behind her.
"They were having a conversation and getting personal with each other and the child was crying.
"The man was leaning forward and grabbing hold of her breast and they were kissing each other."
Mr Melia is not on trial.
The trial continues.
