The video racked up almost a million likes and thousands of comments from stunned TikTokers.
"Almost 5 years of flying to and from college and I never knew," one said, while another blissfully unaware user wrote: "Fun fact... I always thought that was a sound for you need to put your seatbelt on or something".
"Flight attendant here," a third penned, before disclaiming: "While this may be true for some airlines, it’s not for others so if you hear the 3 chimes don’t go panicking just yet."
Meanwhile, one joked: "It actually means 'okaaaaay let's go!'"
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