A passengers on board a Delta Air Lines plane that filled with 'intense fog' was confused after she claims cabin crew made jokes about halloween.
The odorless fog poured from the vents and lingered for over half an hour, but those on board weren't told the reason for the strange mist.
The flight was due to take off from Jacksonville, Florida, and was headed to New York's JFK airport.
Amanda Goncalves, from New Jersey, took a video on her phone of what she described as "intense fog" that she thought could have been related to condensation and humidity.
She told New York station CBS2: "People were wondering why it was lasting so long.
"The flight attendants attendants didn't really make an announcement.
"They just said they were practising for their Halloween haunted house.
"They made a joke of it instead of saying it was from the humidity or condensation."
She said that the fog could have made nervous fliers feel uncomfortable, adding: "I’m not a nervous flyer and neither were the people I was with thank God, but I think if you are somebody who’s already anxious to get on a flight and you didn't really necessarily know.
"I understand seeing a little bit of it with the humidity, but this was like a full fog.
"I think that it could’ve really caused some more insecurities of flying.
"And then they were saying, ‘Get ready for takeoff,’ and it could have definitely caused anxiety for some people.”
Assessing the footage, Alan Yurman, a retired investigator with the US National Transportation Safety Board said it was "not uncommon on a humid day" but was the thickest he had ever seen.
He said: "When the air conditioning system is turned on, and you’ve got cold air meeting whatever the temperature of the cabin was, you start getting condensation.
"I had never seen it that thick before. "
Luckily the mist cleared once the plane was in the air.
Delta Air Lines aid the incident had been related to humidity and that it was not required to report it to the federal Aviation Administration, which regulates civil aviation in the US.
