American Airlines grounds Phoenix flights as temps reach 120 degrees

American Airlines (AAL) has canceled more than 40 flights out of Sky Harbor International Airport (PHX) in Phoenix on Tuesday because of the extreme heat.

The canceled itinerary is impacting flights scheduled to arrive at or depart from PHX June 19-21, between 3 pm and 6 pm.

Seven flights were canceled Monday, with seven flights more flights delayed Tuesday, as temperatures reached 120 degrees in Phoenix. Customers affected by cancellations can rebook free of charge, or cancel their trip for a full refund. 

“The high temperatures during this specific time period may impact flight operations, specifically regional flights that operate on smaller aircraft,” American Airlines said in a statement to Yahoo Finance.

Weather forecasters predict that temperatures will reach 120 degrees on Tuesday, which has caused the National Weather Service (NWS) to issue an excessive heat warning in Central Arizona. The NWS predicts that temperatures will reach 116 degrees on Wednesday. American Airlines does not anticipate further disruption, but will reevaluate in the morning.

An American Eagle jet is seen through heat ripples as it lands at Sky Harbor International Airport in Phoenix.

While airplanes are equipped to operate in different environmental scenarios, not all aircraft are created equal. For instance, the Bombardier CRJ regional aircraft has a maximum operating temperature of 118 degrees. American Eagle (a regional brand of American Airlines) which is operated by Mesa and SkyWest, uses this aircraft to and from PHX.

For comparison, the Airbus aircraft used by American Airlines have a maximum operating temperature of 127 degrees, and Boeing aircraft max out at 126 degrees.

The real issue is that extreme heat can affect a plane’s mechanical abilities during takeoff and landing. As temperatures rise, the air becomes less dense, and thinner air means that more speed is needed for a plane to take off. PHX confirms it is able to accommodate aircraft needs, even in extreme weather. “Planes need more runway in these conditions,” said Heather Lissner, a spokeswoman for PHX. “Sky Harbor’s runways are able to accommodate planes taking off in hot weather.”

According to Lissner, Sky Harbor airport is equipped to handle these obstacles after Phoenix set an all-time record of 122 degrees on June 26, 1990. Flights had to be canceled back then because airline performance charts were not available. Pilots use these charts to predict takeoff, climb, cruise and landing capabilities of a plane. Today, many airlines have performance charts with data for up to around 122 degrees.

To avoid the heat, many destinations that experience extremely high temperatures, like in the Middle East and Central America, schedule flights to take off during the late evening when temperatures are cooler.

In 2013, US Airways canceled 18 flights to and from PHX after temperatures reached 119 degrees.

Brittany is a reporter at Yahoo Finance. 

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