Pop singer Richard Marx helped in-flight airline staff by restraining an aggressive passenger with a rope after he attacked staff.
The "Right Here Waiting" singer had been travelling between Vietnam and South Korea when the passenger began pushing flight attendants and yanking their hair.
Marx, who had a stream of hit singles in the 1980s, used his initiative to tie the disruptive passenger down in a chair with a rope.
Describing events over Twitter, Marx said the "chaotic" episode - which left some passengers and airline staff injured - lasted four hours.
Marx described the passenger as a "psycho", and said that the all-female flight staff were not trained on how to react in a violent situation.
The passenger initially managed to break free from the rope restraint, before turning violent again.
The flight eventually landed safely in Seoul, upon which the passenger was arrested.
Korean Air came under fire from Marx, who he said had not given staff adequate training to deal with disruptive passengers.
Writing on Facebook, Marx said: "The all female crew was clueless and not trained as to how to restrain this psycho and he was only initially subdued when I and a couple other male passengers intervened.
"He then later easily broke his restraints and attacked more crew and another passenger."
Marx added: "Heading home to Los Angeles soon but Korean Air should be sanctioned for not knowing how to handle a situation like this without passenger interference."
In a statement to NBC News, Korean Air spokesman Nathan Cho wrote: "According to the response protocol, Korean Air's flight attendants have subdued the unruly passenger and tied him up with ropes.
"The unruly passenger has been turned over to the police after arrival at Incheon Airport."