Cho Hyun-ah, the Korean Air executive, who delayed a flight in an incident now known as "nut rage", has apologised ahead of questioning by transport officials.
Her father, the airline's chairman, also apologised and said he regretted that he did not raise her properly.
Cho, 40, a former vice president at the airline, also said she would apologise personally to the senior flight attendant who was forced out of the flight on December 5 over an improper serving of nuts in a bag.
Earlier this week, Cho resigned as Korean Air's head of cabin service but retained other executive roles at the airline and its affiliated companies.
Her father and airline chairman, Cho Yang-ho, said on Friday that Cho was resigning from executive roles at all affiliates of Hanjin, the group that controls Korean Air.
Clad in a long black coat, Cho lowered her face as she made brief comments before droves of journalists without making eye contact.
Her apology came in response to simmering public anger over her attitude and the airline's handling of the incident. Some said the apology came too late.
Cho could face legal action if the transport ministry's probe shows that she violated aviation safety law.
She was angered when a flight attendant in first class offered her macadamia nuts in a bag, not on a plate. The crew member was ordered off the plane, forcing it to return to the gate at John F Kennedy airport in New York City. The flight bound for South Korea was delayed by 20 minutes due to the incident.
Her actions caused uproar in South Korea and abroad.
South Korean media called the 40-year-old a "princess" and some Koreans said she was an international embarrassment to her country.
In a separate probe, prosecutors searched the headquarters of Korean Air Lines on Thursday after a civil society group laid a complaint about Cho's behaviour on the plane.