In Las Vegas, an airport built for extreme heat: Mc Carran International (KLAS), Nevada

The soaring temperatures that Las Vegas is experiencing this week could cause grief for pilots at other airports, because heat thins the air and makes it more difficult for aircraft to lift at take-off. To deal with that, pilots need to gain more momentum as they roll down the runway before reaching liftoff speed.

But McCarran International Airport has two built-in advantages that help pilots deal with extreme heat: an exceptionally long runway and one that goes downhill just enough -- 1.1 degree over its 14,505-foot-length -- to help jets reach takeoff speed. The airport was designed that way because of our desert environment.

The alternative at airports that aren't built with extreme temperatures in mind: Aircraft might have to take off with fewer passengers to lessen their weight, or with less fuel, requiring a refueling stop along the way to its destination that normally wouldn't be necessary.

So far during the recent heat wave, when temperatures have climbed to near record-setting levels in the 115-degree range, Southwest Airlines, the busiest airline at McCarran, hasn’t had to disrupt any travel plans, though it could if some variables were to change.

“We’re always in communication with the pilot on every flight,” said Steve West, senior director of the operations coordination center for Southwest in Dallas, which operates a dispatch center monitoring every Southwest flight.

“They have onboard computers that monitor the plane’s weight, the temperature, the wind, the runway conditions and the weather along the route,” West said. “We have similar operational performance formulas in our computers for every plane here.”

As the temperature climbs, the so-called “density altitude” rises. That’s an important flight variable, said Jeff Jorgensen, director of academics for Embry-Riddle Aeronautical University’s worldwide campus in Las Vegas and a commercially rated pilot.

Density altitude is calculated with the level of atmospheric pressure and temperature. McCarran is at 2,181 feet in elevation, but on hot days, the density altitude is closer to 5,000 feet, affecting not only an aircraft’s lift capability but its engine performance.

McCarran has the 27th longest runway in the world and the third longest among commercial airports in the United States at 14,505 feet.

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