Torrid weather in the US spread across major US cities, triggering calls to action for airlines to prioritize traveler and operational safety measures. In an effort to guarantee optimal flight safety and efficiency, the US is urging airlines to recalibrate their operations amid ongoing extreme temperatures. 

The purpose of reducing passenger numbers, luggage, or curtailing fuel is to optimize aircraft performance. As the country grapples with a severe heatwave, temperature records were projected to soar to new highs across about 40 cities. 

High temperatures have been persistent in places like Las Vegas, recording 47 degrees Celsius on July 16, beginning from mid-June, and temperatures in Phoenix reached 48 degrees Celsius, pushing meteorological authorities to make extreme heat warnings in affected states. 

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According to the National Weather Service, the current heatwave phenomena in the southern US are "the strongest" yet. Additionally, experts indicate that the majority of regions are affected by what is described as a "heat dome." 

Airlines taking measures

Moreover, temperatures are reaching unprecedented levels in the US southwest, and Allegiant Airlines, a subsidiary of Allegiant Travel Co., is taking a stance to prioritize travel safety by delaying flights when necessary. 

The region has experienced temperatures soaring above 38 degrees Celsius since June 30, according to NWS data. 

Due to thinner air, as a result of high temperatures, plane engines are not functioning properly, and the upward force generated while maintaining a certain speed is also affected. That means that planes must weigh less, which explains why airlines are reducing the number of passengers and baggage. 

Delta Air Lines flight from Las Vegas to Atlanta experienced delays on July 17 due to aircraft weight caused by the heat. Consequently, passengers willingly left the plane. 
 
“Additional protocols have been put in place to address the operational impacts extreme heat has on aircraft, including loading less fuel to account for weight and balance and schedule refueling along the route when needed,” Delta Airlines said.

American Airlines Group Inc. CEO Robert Isom confirmed that the company is taking action in response to concerns about high temperatures. The airlines upgraded the cooling systems on jet bridges that link the planes and performed early maintenance on the onboard systems.

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