PHOENIX - Extreme heat forced American Airlines to cancel more than 40 flights ahead of Tuesday's expected 120 temperatures. The cancelations are due to heat rising above one of their smaller plane's "maximum operating temperature."

The cancellations mostly affect regional flights as the aircraft in question is one of the airline's smallest -- the Bombardier CRJ. The maximum operating temperature for this plane is 118 degrees while it's "airbus" and "Boeing" models can run up to 126 degrees.

But the dangerous heat is affecting more than just commercial flights.

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"Our limit on this machine is 116 or 117 degrees," says Sky12 pilot Stephen Watkins.

Watkins flies high above breaking news situations to bring the dramatic video to viewers across Arizona. This week, he is checking his temperature gauge a little more than usual.

"It's not like a car where you can just pull over. If you have problems in the air, it's a lot more," Watkins says.

Safety always comes first when lives are at risk and that is exactly why Watkins does not fly when the temperature reaches 116 degrees or higher. The rescue chopper at Phoenix Fire Department also follows the same guidelines, and it's pilot will not fly when the temperature reaches 116 degrees.

"Have people exceeded the maximum temperature before? Sure it happens all the time," Watkins says. "Basically what the factory is saying is this is the limit and if you exceed that, you are taking a huge risk."

The Maricopa County Sheriff's Office says it's chopper pilot does not need to follow the same temperature restrictions as a commercial airline. Rather, MCSO has self-imposed restrictions and higher temperatures decrease performance on the aircraft -- basically meaning they can fly if it's an emergency worth taking the risk for, but that will be up to the pilot.

For more heat-related stories, head to 12 News’s Heat page.