SEOUL >> The former Korean Air executive famous for an inflight tantrum over macadamia nuts pleaded not guilty Monday to violating aviation safety law and hindering a government investigation.

Lawyers for Cho Hyun-ah did not dispute the major elements of the prosecutor’s account of events on Dec. 5 when Cho forced a Korean Air jet to return to the gate. Instead, they are focusing on a technical rebuttal.

Cho spent most of the first day of her trial Monday with her head lowered and hair covering her face. She declined to make any comments when invited to by a judge. Cho’s attorney Yu Seung-nam said Cho is unable to mentally recover from her ordeal as she has been "beaten" by the media.

Cho, who is the daughter of Korean Air’s chairman, achieved worldwide notoriety by kicking the chief flight attendant off a Dec. 5 flight after another crew member offered her macadamia nuts in a bag, instead of on a dish. At the time, Cho was vice president of cabin service at the airline.

Her behavior, dubbed nut rage, caused an uproar in South Korea. The incident touched a nerve in a country where the economy is dominated by family-run conglomerates known as chaebol that often act above the law.

Cho has been in police custody since Dec. 30 and could face up to 15 years in prison if found guilty of all four charges against her.

Prosecutors accused her of forcing a flight to change its route, which was the most serious charge with a maximum prison sentence of 10 years. The three other charges Cho faces are the use of violence against flight crew, hindering a government probe and forcing the flight’s purser off the plane.

Yu, Cho’s attorney, told a panel of three judges that the flight had moved only 17 meters from the gate at New York’s John F. Kennedy airport before it returned, which did not amount to a forced change of an aviation route.

Cho admitted using violence against one flight attendant in first class by pushing her shoulder and throwing an object at her, but denied that she poked the hands of chief flight attendant Park Chang-jin with a book. Yu argued that those acts did not amount to threatening safety on the flight.

Prosecutor Kim Tae-hoon told the court that a flight attendant who witnessed Cho’s tantrum was scared and nervous throughout the 14-hour journey.

"The moment her anger erupted, the vice president did not look like a human. She looked like an angry tiger," said Kim, reading from the flight attendant’s statement.

Head Judge Oh Seong-woo said the judges want to ascertain whether Park will be able to continue working for Korean Air and as a result has summoned the airline’s chairman Cho Yang-ho as a witness.

"Cho Hyun-ah will likely return to society, although we don’t know when," said Oh in remarks that ended six hours of proceedings. "But for the case of Park Chang-jin … whether he can work at Korean Air Lines is of keen interest to the judges."

Two other defendants in the nut rage case also pleaded not guilty. Korean Air executive Yeo Woon-jin was charged with interfering with the government investigation and a transport ministry official was charged with leaking secrets about the investigation.

Yeo, who has worked for Korean Air for more than 30 years, insisted that he did not know that Cho’s actions could result in a criminal investigation even after prosecutors showed evidence that flight attendants reported full details of the incident to him.

"Our company’s executives always make sure during their business trips that cabin service is properly done. I certainly thought (Cho) gave directions as a vice president overseeing cabin service," he said.

Prosecutors also highlighted an email showing that Yeo had asked a Korean Air customer service executive to help prevent legal action against Cho by giving special treatment to the first class passenger who sat near her.