Media playback is unsupported on your device Media caption Steve Evans reports: "A year in prison and a mountain of humble pie"

A former executive of South Korea's national airline has been jailed for one year for obstructing aviation safety during a row over nuts.

Heather Cho forced a plane to return to the gate in New York last December and offload a steward because she did not like the way she had been served nuts.

Judge Oh Sung-woo said it was a case where "human dignity" had been "trampled upon".

Ms Cho has apologised and quit Korean Air, which is run by her father.

Her plane was taxiing at New York's JFK Airport on 5 December when witnesses say she became angry after being served macadamia nuts she did not ask for, and which were still in a bag and not in a bowl.

Image copyright Reuters Image caption Cho's father, Korean Air boss Cho Yang-ho, scolded her over the incident

She ordered the plane to return to the gate and offload the chief steward.

Judge Oh said Cho had treated the flight "as if it was her own private plane".

"It is doubtful that the way the nuts were served was so wrong," he said.

The judge said Cho, who is also known as Cho Hyun-ah, had failed to show enough remorse even after she submitted letters to the court apologising for the incident.

At the scene: Stephen Evans, BBC News, Seoul

The case has resonated within South Korea because of a continuing debate over the way the family-owned and run conglomerates - chaebol - operate.

Some critics say that the way family members are favoured is unfair and mitigates against good business. They say the nut rage case epitomises that.

In court, Cho wept as she read a letter of contrition, a contrition the judge said he didn't accept was genuine.

Apart from the serious debate, it is fair to say that many people may relish the way someone with privilege behaved so badly - and was then penalised for it.

The humiliation may be as heavy a penalty for Cho as the prison sentence.

Prosecutors had asked for a sentence of three years in prison on charges of breaking aviation law, assault and interfering in an investigation.

Witnesses testified during the trial that Cho struck a crew member with the service manual.

Chaebol domination

Her defence team argued that aviation safety had not been violated as the plane was still being pushed away from the gate.

However, the judge rejected that argument saying the plane was classed as "in flight" and she interfered.

Cho, who is the daughter of the chairman of Korean Air, publicly apologised for the incident and resigned from all her posts at the airline in December.

The trial has opened a national debate about the Korean business system, which is dominated by family firms known as chaebols.

Some of the families running these businesses have been accused of high-handedness and acting with impunity.