SAN FRANCISCO (KGO) --
You know it's hot when some planes can't take off or land from a major airport.
If you're flying from the Bay Area to Phoenix, check what type of aircraft you're on because that could be the difference between getting there or not.
American Airlines has canceled about 50 flights scheduled for Tuesday afternoon.
One passenger said Phoenix felt like a lobster pot Tuesday. "Oh my god it was insane, like stepping into an oven," Luis Angel Ortiz said.
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Ortiz flew to phoenix for his college orientation. His flight home was grounded because of the heat. "My flight got cancelled, my connecting flight so I had to stay overnight in phoenix to make it back here," Ortiz said.
RELATED: Watch updated AccuWeather forecast
Retired commercial pilot and Phoenix resident Larry Cochran was on the same flight to SFO. "I was a commercial pilot when it hit 122 in Phoenix and Sky Harbor shut down because the asphalt was so soft the planes were sinking into it," Cochran said. That was about 20 years ago.
He says the runway isn't the problem today. It's the lift. "The hotter the air gets, the thinner the air is."
Some of the smaller aircraft are only certified to operate up to 118 degrees and that's why dozens of flights from regional airports into Sky Harbor were cancelled Tuesday.
Phoenix is expected to hit 120 this afternoon.
So far no flights from San Francisco to Phoenix have been cancelled, that's because the larger jets leaving San Francisco can handle 126 or 127 degrees.
Cochran says passengers flying on larger Boeing and airbus jets shouldn't be concerned about landing in Phoenix. "If it's a safety risk, they wouldn't fly."
And Ortiz says the scorching sun won't cast a shadow on his excitement for freshman year at the University of Arizona. "No, not at all, I love it," he said.
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