On the night of June 18th, the National Weather Service declared an excessive heat warning in Central Arizona, covering areas from Phoenix west to the Arizona-California border. With temperatures expected to exceed 120°F (48.9°C) on Tuesday, going out is not for the faint at heart, however this extreme heat forecast has also affected operations at Phoenix’s Sky Harbor International Airport, with 20 departures operated by American Airlines already cancelled for Tuesday afternoon and possibly more as the day comes.

American Airlines released a statement earlier on Monday, June 19th, that stated that certain American Eagle flights operated by carriers such as Mesa Airlines and Skywest use Bombardier CRJ aircraft, ranging from the CRJ-200, which carries 50 passengers, to the CRJ-900, which carries 76 passengers. However, these aircraft have a maximum operating temperature of 118°F (47.8°C), and temperatures are expected to exceed 118°F between 3 and 6pm.

An American Eagle CRJ-700 at DFW Airport. These aircraft, along with the longer CRJ-900 are unable to operate in the extreme heat that this week’s weather will bring. Photo Credits: Fort-Worth Star Telegram

This isn’t the first time that heat has impacted operations at the airport; on June 26th, 1990, Phoenix experienced its hottest recorded temperature, which was 122°F (50°C). During this time, the airport was closed, with multiple sources citing two factors: the runway’s asphalt construction, which led to unsafe conditions to takeoff, and the fact that the pilot’s flight manuals (which tell pilots how aircraft will perform in different weather conditions or temperatures) did not reach that high. Another heat incident last year involved United Express flight 6186 from Houston to Phoenix, operated by an Embraer E175 aircraft, which had to turn around after reaching Phoenix airspace. The temperature in Phoenix at the time was 120°F (48.9°C), and the aircraft was not rated to land in temperatures above 118°F (47.8°C).

Heat impacts a plane’s ability to take off, as hot air is less dense than cold air. The higher the temperature is, the more speed a plane needs to takeoff, and runways and engines may not be able to accommodate the extra strain that the heat puts on an aircraft’s performance. American Airlines has also announced additional resources for their staff working the next few days in Phoenix, including additional breaks and cooling stations. The temperature on the tarmac can be up to 15-20°F higher than the air temperature due to all the equipment on the ground.

An American Airlines Boeing 787-8 Dreamliner. American’s mainline fleet should be unaffected by the heat. Photo Credits: Nick McGowan

Flights will be cancelled starting with American Eagle flight 3040 to Yuma, AZ at 1:40pm local time tomorrow, and the last scheduled cancellation at the moment is with American Eagle flight 5745 to Santa Barbara, CA. All the flights affected are operated by Bombardier CRJ-700 and CRJ-900 aircraft, and no Airbus- or Boeing-operated flights have been cancelled yet due to the heat; their more powerful engines allow for higher operating temperatures than other regional jets. According to American Airlines, the maximum operating temperature for their Airbus aircraft is 127°F, while for their Boeing aircraft, it is 126°F.

American Airlines is allowing passengers flying during “peak heat times” through Wednesday to change their flights without any additional fees. Contact the airline for more information.

Categories: Flyer Talk