ST. JOHN'S, N.L. - Cursing, yelling and a smack on the head - that's how an "intoxicated" Toronto broadcaster's transatlantic flight ended last year after it was diverted to St. John's, passengers and a crew member told her trial Monday.

Colleen Walsh, 49, has pleaded not guilty to charges of assault, obstructing the operation of an aircraft and causing a disturbance.

Walsh - who has worked for Global Television, CTV, CBC Radio and Rogers TV - sat in provincial court, at times shaking her head at the testimony.

Witnesses told Judge Greg Brown how a profane outburst turned ugly when the seven-hour flight had to land for a medical emergency involving another passenger.

Walsh became increasingly unruly, testified Air Canada service director Guy Marion.

"You sensed that she wasn't happy with the fact that we had landed in St. John's. Just that she was agitated and didn't comply with our demand that she go back and sit down."

Marion described Walsh at that point as "intoxicated" and said she slurred her words and smelled of alcohol.

While on the tarmac during a 50-minute delay, Walsh "got into it with another passenger and started cursing," Marion said.

"The atmosphere had changed. There were a lot of passengers involved at that point.

"Things got out of hand."

The Boeing 767 en route to Toronto from London last March 31 changed course after a female passenger lost then regained consciousness, Marion said. He described the situation as "a serious medical emergency."

He pointed in court to Walsh, saying she was the passenger who came forward to offer first aid to the ill woman.

"She was told that her help wasn't needed," Marion said, noting that a physician on board had already responded to his request for a doctor over the PA system.

"We had to inform her a few times to return to her seat."

Marion said Walsh initially seemed like a happy, pleasant traveller who told staff about her trip to visit family in Ireland. He recalled serving her lunch and two individual-sized bottles of wine, an amount of alcohol he described as "typical" for a flight of that length.

He did not remember serving her any other alcohol.

Defence lawyer Lori Marshall asked Marion whether he ever heard Walsh directly express to him a refusal to comply with his request that she sit down.

"I think I did," Marion said.

"Well ... you didn't testify to it," Marshall replied.

Marion conceded that he was busy tending to the ill passenger and other demands as his workload became "heavy."

Stan Harrington, 67, testified that Walsh was the only passenger standing when a flight attendant asked her to be seated. She did not comply, Harrington said.

"At one point, she asked the stewardess, 'Do you know what's going on? You should tell us what's going on."'

Harrington said he and at least one other passenger told Walsh to "just take your seat."

Walsh then strode toward Harrington, he testified.

"She came down the aisle rapidly toward me and hit me on the right side of the head."

Harrington said it felt like the back of her hand had struck him behind the ear.

"It was quite substantial," he said of the blow. "My head went over (to the left) and I felt a sharp pain."

Harrington said he was quiet as Walsh walked past him and sat down.

"I didn't say anything. I just sat there."

Marion testified that he did not see the alleged attack but heard about it from upset passengers, and that Harrington was asked if he'd like to press charges.

"He said that he did not. He just wanted to get out (of St. John's) and keep on going at this point."

Marion spoke with the captain about the incident and Walsh was removed from the aircraft, he said.

Harrington later filed an assault complaint with police, testifying he considered it his "civic duty" to do so.

Harrington said he was seen by a doctor a day after the alleged incident, suffering from a headache and a bump the size of a nickel.

His wife, Susan Elliott, was seated beside him on the plane. She also pointed to Walsh in court as the woman who allegedly struck her husband.

But Elliott said under cross-examination that she didn't actually see or hear Walsh's hand make contact.

The trial is scheduled to continue Tuesday.