PHILADELPHIA (WPVI) -- Passengers on board a Frontier Airlines flight to Philadelphia experienced a strange mist earlier this week.
Video posted on social media shows the fog billowing into the cabin Wednesday on the flight leaving Charlotte, North Carolina.
Passengers were apparently not alarmed by the event.
Passenger Michael Wilder actually called it "kind of refreshing and calming."
"At first, no one really knew what was happening, but it didn't seem like we were in danger. It didn't seem like smoke from a fire. We then realized that it was coming from the air conditioner," Wilder told Storyful, adding "some [passengers] were light-hearted about it and joked about how maybe cryotherapy is a new Frontier offering."
A Frontier spokesperson said the mist is caused when hot and humid air from outside the aircraft is being rapidly condensed by air conditioning inside creating a watery vapor.
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