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It's Too Hot For Some Planes To Fly In Phoenix (npr.org)
In Phoenix on Tuesday, temperatures were forecast to climb as high as 120 degrees Fahrenheit, causing more than 40 American Eagle regional flights out of Phoenix's international airport to be canceled. NPR reports: American Airlines said in a statement that the Bombardier CRJ aircraft used on some shorter routes have a maximum operating temperature of 118 degrees. For bigger jets, the threshold is higher. The carrier says that, for example, Airbus aircraft have a maximum operating temperature of 127 degrees and that for Boeing, it is 126 degrees. As USA Today reports: "Extreme heat affects a plane's ability to take off. Hot air is less dense than cold air, and the hotter the temperature, the more speed a plane needs to lift off. A runway might not be long enough to allow a plane to achieve the necessary extra speed." Bianca Hernandez, a meteorologist with the National Oceanic and Atmospheric Administration, tells NPR that Phoenix is seeing an unusually strong high-pressure system, which is causing the soaring temperatures.
of global cooling
And that's about 49c for the rest of the world.
This is one effect of global warming no one foresaw.
Time for the city of Phoenix to submit a federal DOE grant to install “goddamn steam” catapults to solve this problem and specify it to be coal fired will be a sure fire way to get approval.
The same phenomenon that allowed hot-air balloons to first lift man to the heavens now grounds him.
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I'd rather be dead in California than alive in Arizona.
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Enjoy it while it lasts!
Wouldn't it be easier to type with your fingers?
It's not like Sky Harbor has short runways. Perhaps they just need to allow the planes to run the whole length.
I wonder how many of these flights could have taken off if the airlines weren't so interested in cramming as many people on as possible.
This actually isn't all that uncommon around the world, at least to varying degrees.
Hot air, at high(er) altitudes is less dense, which will affect the performance of an aircraft to various degrees. The usual effect is that reduces the aircraft's MTOW (Maximum Take Off Weight). If it drops below a certain point, it's either uneconomical to fly the plane, or it can't carry enough fuel to do its job.
Many years ago, Air Canada used to fly to India using Airbus A340s. At certain times of year, it was hot enough in Delhi that they could not take off with sufficient fuel to do DEL->YYZ direct, and instead they would have to make a technical stop in Turkey to refuel the aircraft. This is also one of the reasons why most long-haul international flights fly in and out of Delhi at night. The air is cooler, giving the airliners better performance.
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Nothing but June Gloom this year
https://en.wikipedia.org/wiki/...
Nothing new or myterious. High altitude airports (i.e. Denver) struggle with it all the time. Helicopters, in particular, have to pay close attention to DAlt. A friend told me an entertaining story of spending a week trying to get a chopper to take off from a plateau in Nairobi... combination of a weird pressure change and a heat wave.
Log in or piss off.
If the issue is really air density then how do CRJ planes take off from Denver? Assuming that this page has the physics correctly accounted for then the density of air at Phoenix (331m above sea level) at 49C is 1.059 kg/m^3 whereas the air density in Denver (1600m) is only 0.9978 kg/m^3...and that is if you assume the same air pressure - the density in Denver will actually be a lower than this because the pressure is less.
Perhaps one way to design around this would is to build a longer runway but if that is how they coped in Denver it seems strange that they did not do this in Phoenix given that the effect is far smaller for temperature vs. height so the extension required would be less and 49C temperatures while extreme do not seem to be beyond imagining for Arizona where the record is 53C.
And this is why we need better passenger rail, because it doesn't have this particular issue with heat. We once had a great passenger rail system, but have allowed it to deteriorate to the point of being well behind much of the world. Europe and east Asia certainly have far superior passenger rail systems to the United States. Plenty of trains in those areas travel long distances just like in the United States, so the excuse about having so much area to cover is invalid.
I believe in global warming, got solar panels, hopefully a model 3 someday. The non-stop slashdot stories about global warming is going to cause the end of the world as we know it, is a bit much.
All airplanes have performance charts that you use to calculate takeoff distance, single engine climb gradients, etc. It's not that the airplanes won't technically fly, probably they simply don't have performance data that goes that high. Probably not a big problem in Canada.
Lasted for 3-4 years. She was a co-worker's best friend, I went to Phoenix for a gaming convention (flying buffalo's Starweb) that was held in July and co-worker introduced us.
That's all irrelevant. What got me was crossing the street would melt the soles of my shoes. And I could feel them melting, made me hustle across the street.
We all used to walk to Red Robin's when the convention ended, back then gourmet burgers weren't heard of.
The reason they might not bother in Phoenix is most of the time, it isn't a problem. Also it isn't a problem for the bigger jets with bigger engines, it seems, just the small ones. Well those are a somewhat new phenomena. 20 years ago if you wanted to do a jet a 737 was about as small as they got. You either used that or went with a prop plane for really short routes.
The last big expansion to Sky Harbor was in 1989, before those little regional jets were a thing.
Yep, I was flying into Phoenix 20-some years ago and they were bumping people before boarding acting like the flight was overbooked. I was surprised when I got on the plane and we took off 1/3 full. I think it was a DC-10. I also remember the turbulence on approach to Phoenix being bad from the thermal convection over the desert.
The article is sort of right. What matters more is density altitude, the effective density based on temperature and air pressure. But that's not to say other aspects of the plane are not rated for that temperature because they would then exceed some internal temperature based on temp rise above ambient.
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High temps hurt performance, but no jet magically loses the ability to fly at one specific temperature. They get grounded because they haven't been tested and certified above a certain temp.
Used to love watching F105's taking off at Nellis in summer, Booom! Water injected would add X amount pounds of thrust to get the lead sleds moving fast....
I can understand flying away from Phoenix. But why would anyone choose to live there or go there in the first place? All they have to offer is HEAT. Excessive amounts. Avoid at all costs.
Seriously, does it ever get that hot in Canada regularly? Small wonder the planes underperform in hot places. To be charitable though, they make awesome cold weather planes there, including the only ones that can handle flying into Antarctica in the dead of winter (barely, because you're facing your fuel freezing if you make a mistake)
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I lived there in the late 1980's and it was routine. But slashclimate never misses a chance to spread climate hysteria,
I live in Las Vegas, and we're getting the same high triple-digit temperatures and on top of that most of the Las Vegas valley is at least 2000 feet above sea level vs Phoenix being around 1000 feet. This difference would cause Las Vegas' density altitude to be worse than Phoenix, yet I've heard of no cancelled flights out of Mc Carran airport...
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In the early 1980s, when I was in the Air Force, I worked on jets in Victorville, California.
One hot day (it was only 115 F or so), a buddy of mine brought a fancy digital thermometer with him because he was curious about how hot it was where we worked.
It was 140 degrees.
So yeah, the difference between shade temperature and "on the concrete" can be pretty stark.
The Urban Heat Island effect is most of that - up until 1965, Phoenix was a minor city, and didn't get much past 100,000 until 1950 or so.
Adding people and buildings makes areas a LOT hotter.
All potential pilots learn about "density altitude" in ground school. https://en.wikipedia.org/wiki/...
Got to do my Kegels anyhow...I know what you're thinking, oversized keys.
Hot air is less dense than cold air
If hot air can hold more water vapor than cold air, how is hot air less dense?