"There was a point where I was working in New York and I also lived in L.A., so every four days I was flying," she said, explaining that was "where the fear came from."
"It's like, yeah if you fly twice a year you're good but not if you're flying like twice a week," she added. "So what I did, and what I do recommend to people if you hit turbulence and you're like, 'I don't like how this feels,' I would throw on certain music that I just knew I wasn't gonna die to, which, for me, that was Britney Spears. Like, the archives from when I was young, so like the Oops!... [I Did It Again] album."
As she and Clarkson, 39, laughed together about Fox's revelation, the Transformers actress then mimicked Spears' signature sound, singing a quick snippet of her track, "I'm Not a Girl, Not Yet a Woman" — much to Clarkson's delight.
"That's not the soundtrack to my death. So, that always made me feel better," Fox quipped.
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Adding to her hilarious conversation with Clarkson, Fox continued speaking about how she knew she wouldn't meet her maker while listening to Spears.
"You're not gonna meet God on a like, 'Oh baby, baby,' and then you're dead and you know all the mysteries of the universe in that moment," she said, then impersonating Spears' vocals on the song "Oops!... I Did It Again" from her album of the same name. "So for me, that was really helpful."
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Fox also said that her rule for flying doesn't always just apply to music from Spears, but other similar upbeat artists as well.
"Honestly, just make sure you're picking music that's like that," she said. "Like Backstreet Boys or [The Weather Girls'] 'It's Raining Men.' ... Ain't nobody dying to that song."
As Clarkson joked that the hit '80s track is "not on the playlist to death," she later added that Fox should create her own Spotify playlist filled with her best recommendations.