When you see flight attendants, you may not think that their lives are that complex. But here are some secret facts you may not know about them regarding their job, their skills and their life overall.

What are the secrets you don't know about flight attendants

A South Korea-bound Hawaiian Airlines passenger faces a maximum 20-year prison term after a drunken disaster in the skies, reports the Honolulu Star Advertiser.

Kyong Chol Kim, 48, pleaded guilty and told a federal judge he didn’t remember being put into flex cuffs after lunging at a flight attendant.

He was charged on Monday with interfering with flight attendants and flight crew members. He faces a maximum 20-year prison term at sentencing in July.

Under the terms of his plea agreement, however, the Government will recommend he be released at his sentencing date. Kim has been in custody since late February.

He’s not getting off lightly by any stretch; Hawaiian Airlines says it cost $US172,000 ($A250,000) to return the aircraft to Honolulu and then to resume the flight for the presumably vexed remaining passengers. The court will reveal his fine at sentencing.

Kim arrived in Honolulu on February 25 2019. US customs officers refused him entry at the time for not having proper documentation. They took him to a federal detention centre until they could put him on Hawaiian Airlines Flight 459 back to South Korea two days later.

Witnesses saw a DFS worker hand Kim a package containing a bottle of whiskey in the duty-free zone prior to takeoff. It is not clear who purchased the whiskey.

Kim said he was exhausted at the time and didn’t realise how strong the whiskey was.

Lawyer Sara Ayabe said Kim finished the bottle by the time the flight attendants began the flight’s first service, bothered a 10-year-old sitting next to him and stepped on the boy’s shoulder to lunge at a flight attendant.

Ayabe said Kim yelled in Korean that he was going to get the flight attendant and that “he’s a criminal and could cause trouble”.

Passengers and other flight attendants put flex cuffs on Kim and secured him at the back of the aircraft. The pilot decided to turn around the plane about three hours into the flight after receiving reports Kim was continuing to yell and fighting to get out of his restraints.

Judge Derrick K. Watson told Kim at the hearing he could also expect to be barred from entering the United States and from applying for citizenship.

Through a Korean interpreter, Kim asked how long he would be barred and whether that applied to tourist visits.

Judge Watson told Kim he would most likely be barred “in perpetuity for any purpose”.

It is not the courts but the executive branch of the United States Government, that can refuse entry into the country.

This article originally appeared on the New Zealand Herald and was reproduced with permission