It's Too Hot For Some Planes To Fly In Phoenix (npr.org) 286
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.
120 whatchyamacallit (Score:5, Insightful)
And that's about 49c for the rest of the world.
Re:120 whatchyamacallit (Score:5, Funny)
To be honest, it mostly doesn't.
Re:120 whatchyamacallit (Score:5, Informative)
And you're perpetuating a common falsehood, that's been thoroughly debunked.
It's a nice story, but it's not true. The origin of the scale comes from Ole Romer who set freezing of water at 7.5, and human body temperature at 23.5, and boiling point at 60. Fahrenheit didn't like this scale because of the fractions so he just bumped everything up by 0.5. Freezing at 8, body temperature at 24. Later on he multiplied everything by 4. Freezing now becomes 32, body temperature 96, boiling at 212.
But there's probably more to the story, since 1oF increase in temperature increases the volume of Mercury by 1 part in 10,000. Did this play into it? No one knows.
Interesting story. I highly recommend Veritasium's video on the subject:
https://www.youtube.com/watch?... [youtube.com]
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But there's probably more to the story, since 1oF increase in temperature increases the volume of Mercury by 1 part in 10,000. Did this play into it?
No more so I guess than the length of a 1-second pendulum being near as dammit 1 metre or atmospheric pressure at sea level being near as dammit 1 bar.
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But there's probably more to the story, since 1oF increase in temperature increases the volume of Mercury by 1 part in 10,000. Did this play into it? No one knows.
Actually, we do know. That "multiplied everything by 4" was due to the introduction of the mercury thermometer, which allowed for more accurate measurements than the alcohol thermometers that had been used previously.
Fahrenheit increased the numerical scale to match the resolution of his measurements for the same reason he rounded off numbers before; he preferred using integers.
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Arizona is only habitable by humans because of very wasteful technology. Without that technology the vast majority of the inhabitants would flee.
You would be the first to go if you couldn't use air conditioning.
Re:120 whatchyamacallit (Score:5, Informative)
The core value of metric is not just the decimal calculations, but that the units for different measures, such as weight and volume, fit together in an easily comprehensible way. No more medieval mess of fluid ounces, cups, pints and gallons.
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Planck units work much better.
C = 1
G = 1
Kb = 1
etc
https://en.wikipedia.org/wiki/... [wikipedia.org]
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But the Planck scale includes no convenient equivalent of the metric shitload, or stere. Volumes would be expressed in inconvenient huge numbers, like Zimbabwean hotel bills.
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I don't know if this is a common UK thing - and possibly age related as younger people here mostly use celcius - but I think of low temperatures in celcius and high temperatures in fahrenheit.
So for me, 0 is freezing, negative numbers are really cold (-5C to -6C is about as low as I've seen it get here), 0 - 10 is varying degrees of chilly - all in celcius.
I still think of hot as 80s and 90s though, and if someone tells me it's 30C I do the mental conversion to fahrenheit to get a sense of just how hot tha
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I hate it when I get a hotel where I can't set the temp to 21.5C. 21C is too cold.
What are you, some kind of lizardman? Anything over 10C is too hot.
Re: 120 whatchyamacallit (Score:5, Insightful)
Garbage. You think it's "easier to relate to temperature in F" simply because that's what you are used to. Nothing more.
It would be the same reasoning to claim "It's so much easier to say this in English. Why do those foreigners insist on speaking their miserable language?"
Celsius is the international standard. The USA is a muddled backwater because it clings to outdated measurements.
Re: 120 whatchyamacallit (Score:5, Insightful)
I'm intrigued by "not precise enough", the difference is less than a factor of two. If precision is actually required then you'll be using decimals no matter what.
Re: 120 whatchyamacallit (Score:5, Interesting)
One admittedly minor advantage of Celsius is that most of the temperatures humans are interested in only need two digits. So your air-con can save on an extra 7-segment LED module, or you can have 3 and go to 0.1C precision which is over 5x better than a 3 digit Fahrenheit scale.
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The most obvious relevant use case would be body temperature. Having a few degrees between healthy and dead seems like a useful thing. Meat cooking temperatures can also be subtle. Done versus dried out is a pretty thin line in some cases.
Re: 120 whatchyamacallit (Score:3)
That's just Canada in a nutshell.
Here in the Canadian Prairies, we measure distance in time (hours & minutes).
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Don't forget tyres. The hole in the middle (actually the object that goes in the hole) is measured in inches and the width is measured in millimetres with the height being a ratio of the width. My tyres, 15/70/235, 15 in, 70% height of width and 235 mm wide.
Re: 120 whatchyamacallit (Score:2)
The handy thing about that is that there are no similar numbers to muddle up as the units are so different.
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Mostly true, but I have come across 15/75/235 tyres, just a little taller, and easy to forget if yours are 70 or 75. There is also a surprising difference in different brands that claim to be the same size but when you compare by putting them side to side, one can be an inch taller then another, not good if putting them on the same axle or different ones on a 4x4.
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ABS MIGHT help, but it is generally better to avoid the risk if your life depends on it.
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Re:120 whatchyamacallit (Score:5, Informative)
The original measurement was that 0C was the freezing point of water at sea level. This has since been changed so that 0.01C is the triple point of water, exactly -- or more specifically, 273.16K . (The triple point of water is the temperature and pressure at which water can exist in all 3 states simultaneously, which is 273.16 K (0.01 C) at 0.611657 kPa (0.00603659 atm)).
This was chosen because the triple point is at an exact temperature AND pressure. If either the temperate or the pressure are changed then water cannot exist in all 3 states. There's no "at sea level" here, as that can be somewhat arbitrary, thus leading to a fluctuating 0C.
https://en.wikipedia.org/wiki/... [wikipedia.org], if you want to read more.
The vast majority of SI units are specified so that they can be measured in a lab -- the kilogram being an obvious exception to this, but that is something that should be resolved soon. The definitions of all of the SI units is actually fairly fascinating, and I recommend reading at least the Wikipedia article about them.
https://en.wikipedia.org/wiki/... [wikipedia.org]
This lists the original measurements (such as the metre being 1/10,000,000 of the distance from the North Pole to the Equator (through Paris, for some reason)), and how the definition changed until the current definition was reached (a metre is the distance light travels through a vacuum in 1/299,792,458 seconds).
It gives reason to all of the measurements, and shows how they are all (mostly) interlinked, again with the obvious exception of the kilogram.
Incidentally, the inch, which is the basis for all imperial units of measuring, is 25.4mm exactly. So all measurements in the US are actually based on SI units. https://en.wikipedia.org/wiki/... [wikipedia.org]
All weights are also based on SI units: https://en.wikipedia.org/wiki/... [wikipedia.org]
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Indeed - 10cm x 10cm x 10cm = 1 litre. Fill this with 'standardised water' at 4C (the maximum density of water) and you get the original definition of the kilogram. But again this would vary depending on the water you used and the percentage of it that was heavy (hence the 'standardised'). For normal day-to-day usage, 1l of water from the tap is a kilogram. For science, 1l of water is _approximately_ a kilogram, and approximately isn't good enough.
So they switched to the current reference, the Internati
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You mean how like a pint (16 fluid ounces) weighs a pound?
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The UK uses miles and mph still, but use kilograms for weights.
Ireland, on the other hand, used kilometres and mph for many years, until we finished switched to km/h a few years ago. Over a (long) period of time (like, since 1970 or so -- around the time we entered the EU), all road distance signs were switched from miles to kilometres, with all new signs being in kilometres. Speed limits (and car speedometers) were in mph, so we all got really good a calculating five-eights in our heads so convert km to
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Applies to car tires too. 225/xx R16 means 225mm wide and 16inches wheel size. two different units on the same product...
Re: 120 whatchyamacallit (Score:3)
That's not a knife, this is a knife.
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Get out of that polar expedition sleeping bag and say that again.
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It was 16C yesterday and I was going around in shorts. All this means is that different people are comfortable with different temperatures. It also varies by activity level, and time of year. When you've been in -20c to -30c for a few months, a day at 0-3c you'll see people shedding their coats and hats to walk outside and enjoy the warm sunshine. Works just the opposite in summer too.
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It doesn't matter if it's arbitrary. None of the key units in a measurement system can be defined by a universal constant that people in the street can relate to (wavelength of cadmium light anyone?).
It's designed to be rational, not meaningful.
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It doesn't matter if it's arbitrary. None of the key units in a measurement system can be defined by a universal constant that people in the street can relate to (wavelength of cadmium light anyone?). It's designed to be rational, not meaningful.
So when I'm working in decimal inches, you find that to be equal to the metric system?
As for rational, sure. the relationships between units is nice. One of the reasons I prefer to use the metric system. But in here, and where perfectly normal posts get modded to oblivion because they propose any other view than that the metric system is unquestionably superior in every way....
I'm not convinced that being rational is all that important to the metric warriors.
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The least arbitrary scale would probably be Kelvin, which at least defines a non-arbitrary zero. Find a second non-arbitrary point and divide the space in between them in a sensible way and you're set.
Dividing by a multiple of 10 makes the most sense. Why? Because most people use a decimal number system. It would be something most people would immediately intuitively understand.
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This has already been done: The triple point of water, which defines the Kelvin scale by putting it at 273.16 K. It also defines degrees C, by using the same scale as Kelvin, but translating it 273.15 degrees down.
For historical reasons, though, this doesn't use your arbitrary divide by tens scheme. The w
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My argument isn't that dividing by ten doesn't make sense. It certainly does for people who have ten fingers. It does raise the question of why we don't use units of 20 with our toes and all.
It has more to do with the base-10 decimal system for numbers than with the number of fingers. Dividing by 10 is better, because it only involves moving the decimal point.
Of course, for temperatures, this point is irrelevant, because we don't usually divide or multiply them, or convert them to other units (and if we do, we use Kelvin).
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How are we defining arbitrary? There was a reason that boiling and freezing were selected as measuring points, but they didn't HAVE to be so does that make the measurement arbitrary? What measuring system which needs to cover an infinite set of possible cases isn't arbitrary by that definition?
And you have uncovered the the answer. They are all arbitrary. Even the boiling and freezing points. The composition of the water and atmospheric pressure and even supercooled water make for some head scratching standards.
The thing is, metric isn't better because it's "not arbitrary", and it's proponents don't prefer it because they can't work in imperial. It's just easier to use, which is surely the only method by which a measuring system can be judged given use of the decimal point and a complete specification of what is being measured.
What the metric system has going for it is the systematic relationship within it. tens hundreds thousands, and so on. And when I can work with it, it is my preferred measurement system. But the arguments for superiority of one over the other are just wrong. I'll concede it is better whe
Coal Powered Steam Catapults (Score:5, Funny)
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.
Isn't it ironic? (Score:4, Insightful)
Re: Isn't it ironic? (Score:2)
Not exactly the same phenomenon. Heat outside a hot air balloon will ground it even more easily than it grounds an airplane. That's why hot air balloons usually fly in the mornings.
Re: Isn't it ironic? (Score:5, Informative)
I'm up at 0315 for a training flight in a balloon this morning. Sunrise is at 0450. I intend to have landed by 0730, and this has little to do with the heatwave we're experiencing.
The reason balloons operate near sunrise and sunset is not specifically to do with the temperature, but actually to avoid thermals, which are generate by temperature differences (strictly, different heating rates of areas on the ground). Thermals that would be fairly pathetic for a glider pilot (which I used to be), say anything up to 200 ft/min up or down, would be enough to cause issues for balloons. Meaningful thermals (more than 200 ft/min up or down) would make the balloon very hard to control, since up and down control is the only way a balloon pilot can steer and uncommanded up and down movements (especially on landing!) mean you don't know where you're going to end up.
As far as temperature is concerned, the balloon flies a bit better in summer but can carry less weight. The balloon is less buoyant in hot air which is thinner as the parent(s) point out, so in general you can carry more weight in winter (or at lower altitudes - "pressure altitude" is still a relevant thing to look up). The big deal with temperature for me is actually that the fuel pressure drops a lot with falling temperature (liquid propane expands and contracts far more than water does). This means that in winter, less fuel is supplied each time I burn, meaning less heat output per burn. I have to burn more frequently to maintain level flight, or constant climb/descent rates.
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*fist bump*
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I think what's ironic is that the company that built the planes is known for building snowmobiles
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I ski what you did there.
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Nearly like rain or your wedding day.
I'd Rather (Score:3, Funny)
I'd rather be dead in California than alive in Arizona.
-Lucille Bluth
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Arizona overall isn't a hot state, it's just Phoenix which happens to reside in a valley. If you actually go south to Tucson, it's generally about 5 degrees cooler, and to the north lies Flagstaff, which this year had the longest duration ever for its popular snow skiing resort being open (from October til May.) It also snows much of the year at Four Peaks, which is about a 1 hour drive from Phoenix.
You may as well say that California is a hot state because of Death Valley, which is always hotter than Phoen
Not that uncommon worldwide (Score:5, Informative)
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.
Re: Not that uncommon worldwide (Score:2)
I've never been to India, but I've been close. Either way, this is also pretty common in the Middle East and North Africa. I've had flights delayed, had to take off at odd hours, and have been aboard planes where the pilot chickened out and they got like a dozen people to get off. I am kinda sure that I have had a delayed flight in Mexico, for the same reason, as well.
Re: Not that uncommon worldwide (Score:2)
I know it was probably meant tongue in cheek, but "chickened out" is a little harsh.
For those not familiar with aviation, calculating takeoff performance is some fairly simple maths. If the data says you won't take off in the allotted space no amount of hope will help.
As others have mentioned, some data didn't go above about 50 C (122 F), so whilst a pilot could extrapolate takeoff performance, flying into the unknown probably doesn't make them happy (and is very likely to be illegal). In that case, I'd be
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Buncha pussies! ;-)
YYZ (Score:2)
Good song.
You can send the Heat to Seattle, Please (Score:2)
Re: You can send the Heat to Seattle, Please (Score:2)
It hit 78, at my house, today. It was also really humid. I thought I was going to melt.
I used to live in much warmer climates. It sure as hell wouldn't bother me when it is 78f outside. But, I have acclimated and this touches on a broader point.
I don't care for the heat. I start getting pissy at about 90. I get pissy at lower temps, but only if it is humid.
I do have a point...
Anyhow, you're possibly more correct than just from having the AC issues. We adapt to our environs. At least, we seem to. If our temp
Re: You can send the Heat to Seattle, Please (Score:2)
...
You can Google this. The record is -50 and this year was -43.4. That is at a lower elevation.
You can be as skeptical as you want. It's not hard to look it up.
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You weirdo.
Density altitude (Score:5, Interesting)
https://en.wikipedia.org/wiki/... [wikipedia.org]
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.
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Well both heat and cold can do some major screw-ups to other mass transport systems. Here in Canada you see cases where in the summer train speeds are either heavily reduced or the trains are stopped from going down the tracks. Usually only happens when the temps hit 30C for more then a couple of days. Rail deforming and causing derailments is a problem, but on top of that the rails are also susceptible to the cold. So if we see a period of -30C several days in a row they also have to slow down.
Think it
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I once took the train across Canada in winter. We were delayed several times in Manitoba and northern Ontario because they had to wait for crews to come out and weld in new sections of rail because a flat spot on a wheel of the freight in front of us had shattered the rail.
They actually run a (small) electric current through the rails, and can detect breaks pretty quickly and narrow it down in time to stop the following train.
More than Air Density? (Score:2)
Perhaps one way to design around this would is to build a longer runway but if tha
It may just be runway length (Score:2)
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.
Re:More than Air Density? (Score:5, Interesting)
I have a few guesses as to why they don't have this problem in Denver but they do in Phoenix. One you point out is that Denver likely has longer runways. Why not extend the runways in Phoenix then? Likely because this happens so infrequently that they did not want to go through the expense of extending the runway. I got to talking to an engineer that works on airports. As I recall the runways are dug something like 30 feet into the dirt and filled with concrete. That's a lot of concrete to make up for a few hours of inconvenience every few years. This is not your typical concrete and the surface is engineered for keeping traction in all kinds of weather. Every extra foot of that runway must be very expensive.
Another possibility is that airports in Phoenix are older and with improvements in optimizing airframes over the years for some norm the margins got slimmer. This means that over time the airplanes needed longer runways but the airport couldn't extend the runway even if they wanted to. Old airports tend to have the city build up around it and pen it in from expanding.
It could also be that nothing changed physically but the rules under which they operate did. It could be that somewhere in the world an airplane didn't quite make it off the runway in the heat so the FAA decided that the rules on the safety margins had to be changed. It's quite possible every aircraft that wanted to take off could do so, and in the recent past the FAA would have allowed it. But because of a desire to maintain an abundance of caution the FAA grounded those flights.
I recall someone pointing out that we have not seen a commercial jet crash that resulted in fatalities since 2001. We've seen big planes crash since then but no deaths. We've seen people die in plane crashes but not on a major airline on a regularly scheduled flight. I think the FAA would like to keep it that way as long as possible.
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https://en.wikipedia.org/wiki/... [wikipedia.org]
Re:More than Air Density? (Score:4, Funny)
On the radio today, they said this heatwave (7 days of 49C IIRC) is a one in 200 year thing and hasn't happened since last year.
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On the radio today, they said this heatwave (7 days of 49C IIRC) is a one in 200 year thing and hasn't happened since last year.
And there probably won't be another summer like this until next year.
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I found a cool source:
https://www.pilotsofamerica.com/community/threads/max-operating-temperature-for-airplane.104126/
According to these guys, there is probably no physical limit that absolutely prevents the CRJ from operating safely above 118 degrees, given runways that are long enough for the gross weight. The problem is that pilots and airlines are not allowed to use the laws of physics, such as the ideal gas law, to calculate the required runway length to takeoff at a given weight and temperature. Ins
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Yes.
On top of that aircraft engine cooling systems also don't work as well when the ambient temperature is high.
An extreme example of that was very early QANTAS aircraft (Royal Aircraft Factory B.E.2 - 67kW/90HP) where on hot days they didn't have enough power to make it out of ground effect and had to avoid trees. They were operating in an area as flat as the prairies but drier, so not very many trees.
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Denver is always high up. Phoenix isn't always so hot.
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You're on the right track. The ability to get airborne is one constraint; you also have to maintain a certain minimum rate of climb if you lose an engine.
Tire speed is another constraint. The higher the density altitude, the faster the airplane has to go to develop lift. If that speed is above the maximum safe rotational speed of the tires, it doesn't matter how long the runway is.
Slashdot global warming doomsayer (Score:2)
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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.
The problem is not global warming, or at least not the primary one. The problem is it is currently more profitable to lie and pretend it doesn't exist, is a scam from china, isn't our fault anyway, there is nothing we can do, etc, etc.
The problem is those lies, like so many others work remarkably well quite often, well that and the fact that people care about the near term. Sacrificing, well, anything, for the long term, or the planet, is, well, not particularly American. It is all rather sad.
If we had c
Sort of (Score:4, Informative)
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Yes, they warn you about taking off from high airstrips on warm days. Everything feels OK, except the airspeed is not increasing very fast and the end of the runway looks mighty close...
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Time to bring back water injection! (Score:2)
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....
Phoenix? (Score:2)
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.
Funny... (Score:2)
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...
Re:Global warming. (Score:5, Interesting)
This is one effect of global warming no one foresaw.
Uh, it's actually a pretty well-known issue. Lots of flights in the Middle East tend to be scheduled at night or in cooler parts of the day to avoid such problems. Larger planes with more powerful engines can often cope with higher temperatures, but it's a problem for less powerful planes that can't accelerate enough to get off the ground with a short runway.
It's a known issue. But so far not a common-enough one to extend runways or do expensive plane redesigns.
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Waiting to fly at night is one solution. Another solution is to lighten the load, by limiting the number of passengers, or carrying less extra cargo. Shorter flights can still take off in the heat since they have less fuel to weigh down the aircraft.
Lighter loads (Score:2)
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buillshit.
over 20 years ago it was hotter in Phoenix, 122 degrees.
second of all, jet aircraft regularly operate in parts of the world that get hotter than that
Re: Global warming. (Score:2)
There used to be special hot&high versions of an aircraft, with somewhat overpowered engines. They don't make this kind of aircraft anymore because too powerful engines are not economical.
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over 20 years ago it was hotter in Phoenix, 122 degrees.
Yes, also related to global warming. Local temperatures are a noisy signal on top of a gradual rising trend.
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So yes, they can fly, but airlines are in the business of making money with getting passengers somewhere as a secondary consideration.
In those hotter places they have planned for it and they know they can make a return.
Re: Global warming. (Score:5, Informative)
Phoenix has only had three previous days with a temp of 120F or higher, all occurring in 1990 or later. Such temps were not recorded there any other time since 1890s.
Urban Heat Island (Score:3, Interesting)
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.
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Re:Global warming. (Score:5, Informative)
Re: Global warming. (Score:2)
Not going to argue as the GP probably misremembered. However temperature is measured as ambient air temperature, and in the shade.
A runway in direct sunlight is likely to heat the air above it, providing there's no wind continuously replacing the air mass. It'd be interesting to work out by how much.
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...in the shade. Not on a runway that is by the very definition of what a runway has to be like is right in the glaring sunlight, with airplanes pushing their hot exhausts right across it.
One might imagine that temperatures could probably be a bit higher in those circumstances.
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Unless the runway length is too short for the reduced performance, pilots care about the Density Altitude, more so aloft at the altitude they plan to fly. It also affects:
Reduced rate of climb.
Increased TAS (but same IAS) on approach and landing. TAS = true airspeed, IAS = Indicated airspeed
Increased landing roll distance.
https://en.wikipedia.org/wiki/... [wikipedia.org]
And from a FAA safety pamphlet:
Why Does Density Altitude Matter?
High Density Altitude = Decreased Performance
The formal definition
Re: Global warming - not really (Score:2)
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.
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And this is why we need better passenger rail,
Yeah. Good luck with that in the heat [news.com.au].
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And it's cheaper and more comfortable for the passengers, too, while allowing the train service to still operate at a fat profit.
It takes longer? Yes. But realize that you can travel in a sleeping wagon for the price of a sardine can ticket on a plane. Yes, that still takes 8 hours instead of 2, but it's 8 hours you have to sleep anyway. Check in at 9pm, sleep in your own cabin with your own toilet and your own washing facility, wake up refreshed, take half an hour or hour at your own leisure to refresh, pu
Re:its because... (Score:5, Funny)
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Offloading passengers on hot days is normal practice. Some people get pissed off, and you have to compensate them, but at least you make something on the flight. Cancel it altogether and you make nothing.
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4 out of 5 doctors approve: https://i.redd.it/wfbt456v0wqy... [i.redd.it]
Re: (Score:2)
You owe me a keyboard and an explanation to my boss.
Could you at least put a NSFW next to it?