AN American man acted "negligently" before the emergency grounding of a transatlantic flight in a row started over crackers, a prosecutor has said.
Jeremiah Mathis Thede (42) behaved in a manner likely to endanger the aircraft and should be convicted, the barrister told jurors in his Antrim Crown Court trial on Thursday.
The Californian denied being aggressive towards cabin crew after they refused him pre-flight crackers during a United Airlines service from Rome to Chicago last June.
His lawyer said airline witnesses had contradicted each other and had overreacted to a series of relatively minor events.
The service diverted to Belfast after staff became worried and claimed they had been approached by passengers - some even moving children away from the agitated accused. None of the fellow travellers have given evidence.
Prosecution barrister George Chesney said: "There were a number a events, a number of actions during the course of this flight from Rome, UA971, and each event on its own is very much like a brick building up a wall.
"One or two or three don't constitute a wall but when you build all the bricks together to form a wall there is a course of events applied to this case in which the prosecution say that Mr Thede negligently acted in such a manner.
"He negligently acted in a manner likely to endanger an aircraft."
Mr Thede was on an 11-hour United Airlines flight from Rome to Chicago, connecting to San Francisco, on June 20 last year.
The accused, from Berkeley, has previously described how he was down to his last dollars following a long trip and had eaten only an apple during five hours waiting at Rome airport for the delayed flight home.
He has said he requested crackers immediately upon boarding, then repeatedly during the flight, because he was hungry.
Unable to sleep, he proceeded to repeatedly go to the bathroom and search through his luggage while organising contacts from his long European trip. Flight attendants claimed he left his meal tray obstructing the aisle.
Mr Thede's barrister Aaron Thompson quipped that the whole trial was a bit crackers.
"This is about a case of misinterpretation, misunderstandings and overreactions."
He said his client allegedly swore at the air hostess who denied him the snack and said such conduct was not gentlemanly.
But he added: "It was a verbal dispute that ended in a verbal dispute."
When the woman in charge of the cabin, Sheila Wire, admonished him about his behaviour she said he failed to comply, asking her: "Are you done?"
Mr Thede said he spent most of the remaining time asleep.
The 11-member jury is expected to retire on Friday to consider its verdict following a week of evidence.