South Korea’s transport ministry said the carrier could face up to 21 days of flight suspensions or shell out a £830,000 fine for breaking aviation law.
Cho Hyun-ah, the daughter of Korean Air’s chairman, went crackers after she was served macadamia nuts in a bag instead of on a plate, forcing the aircraft to return to the gate and ordering a crew member off the December 5 flight.
She later resigned from executive roles including head of cabin service amid a storm of criticism over the incident, which made world headlines and spawned parodies on the internet.
Demand for macadamia nuts also rocketed, with Auction, a South Korean unit of eBay, saying sales surged nearly 1,200 per cent during the five days to Sunday without any promotions.
And the website of e-commerce firm Coupang showed Mauna Loa macadamia nuts were out of stock.
The transport ministry said the airline would also be punished because Ms Cho lied during the inquiry into the incident and the captain was negligent in his duties.
It said Ms Cho used abusive language to flight attendants but could not ascertain if she used violence.
The government probe has highlighted the tyrannical behaviour of a top Korean business family and the transport ministry said it would also investigate whether the airline’s corporate culture poses safety risks because Ms Cho, 40, overruled the captain to force the plane to return to the gate.
Ministry director Lee Gwang-hee said the airline’s punishment would be determined by a separate committee that could decide to increase or lessen it.
Park Chang-jin, the attendant forced to leave the plane, later told South Korea’s KBS television network that Ms Cho had shamed and insulted crew members. A first-class passenger told Yonhap news agency that she yelled at flight attendants who kneeled before her, pushed one’s shoulder and threw an object at the cabin wall.