DENVER — It hit 99 degrees in Denver on Wednesday. That may leave you feeling a little sluggish, but it’s not just people feeling the extreme heat.
Airplanes also struggle in the high temperatures.
"One of the things about summertime flying is that heat does have an adverse effect on aircraft performance," said 9NEWS Aviation Expert Greg Feith. "The hotter it gets, the worse the performance is on the airplane."
He said extreme heat makes the air less dense or thinner. Pilots call it high density altitude. That makes it more difficult for large airplanes to get off the ground.
He said the planes get lift when the aerodynamically shaped wings come in contact air molecules which force the aircraft upwards. The more molecules there are, the easier it is to take off.
Denver International Airport (DIA) already has some of the thinnest air in the county with its elevation more than a mile above sea level. Add 99 degrees of heat, and air gets even thinner.
Feith said planes fully loaded with fuel and passengers need extra speed to get off the ground. So they need extra-long runways for takeoff on a hot summer day in Denver.
That was a major issue with the city’s old airport.
“Back when old Stapleton was in existence, there were a lot of times where the airplanes were weight restricted," said Feith. "To take off with a full load of passengers and baggage, planes would have to have less fuel, so they would have to stop off somewhere close by like Kansas City to refuel.”
He said DIA was built with high heat and thin air in mind. It has the longest runway in the country at 16,000 feet which is more than 3 miles long.
The other 5 runways at DIA are not quite that big, but at 12,000 feet, they are still much longer than the average runway in America.
Feith said the best time to travel in summer is in the morning or late evening because take-offs are easier and smoother. And you can also avoid a lot of the turbulence, like the wind shear diverted 51 planes on Sunday.
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