Tim Bradley, 32, is said to have downed wine and beer before threatening fellow passengers and spitting at cabin crew.
Witnesses claimed he brandished a shard of glass after being refused more alcohol on the Boeing 747.
The drama unfolded on the 9 hour 40 minutes British Airways flight from Pheonix, Arizona, to Heathrow.
Bank worker Lesley Lewis, 31, was near Bradley in business class, and said: “He was shouting at customers and crew, swearing, stumbling about the cabin.
“At one stage I could see him holding a broken glass, ready to attack the crew and talking to himself.”
Lesley, of Southampton, added: “When he got back to his seat I could see him holding the broken glass in his hand.
“He was saying to people around him, ‘Why have I been f****** picked? I’ll stab the pilots if they want.’
“I and many other passengers were petrified.”
The American businessman, who works as a mortgage consultant, was arrested on the tarmac as soon as Flight 288 landed at Heathrow just after 1pm on Saturday. He was charged with being drunk on an aircraft and common assault.
He appeared at Uxbridge Magistrates' Court in west London on Monday and was remanded in custody.
He will re-appear for sentencing at Isleworth Crown Court in west London on September 23.
BA said: “We do not tolerate abusive behaviour towards are staff or customers.”
