Phoenix Sky Harbor International Airport grounded flights due to extreme heat for the first time in 1990. It happened again more recently in 2013 and 2017.
But why can't planes fly in certain temperatures? Turns out, it has to do with performance data provided by plane manufacturers and airline safety procedures. For more on what exactly that means, listen to this week's episode of Valley 101 podcast. 
In this episode, you'll hear:

What it was like in 1990 when Phoenix Sky Harbor grounded flights.

What four components are necessary for planes to fly. 

Kenneth Wood, an American Airline pilot, explain why "performance data" was integral to planes being grounded in high-heat situations.  


Related reading: 

Nope, turns out it was technically never too hot to fly out of Phoenix

Extreme heat could delay Phoenix flights

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