Posted on 07/14/2015 2:41:12 PM PDT by Oldeconomybuyer
Edited on 07/14/2015 3:25:30 PM PDT by Sidebar Moderator. [history]
Long-haul flights are getting longer due to stronger winds caused by global warming, according to a study.
Scientists linked a small increase in return-journey times of long-haul flights with an increase in the variation of the jet stream, the high altitude air that flows from west to east.
Just one minute's extra flight time would mean jets spend approximately 300,000 hours longer per year burning roughly a billion additional gallons of jet fuel, they said.
Kris Karnauskas, associate scientist at Woods Hole Oceanographic Institution, said: "Longer flight times mean increased fuel consumption by airliners. The consequent additional input of CO2 into the atmosphere can feed back and amplify emerging changes in atmospheric circulation."
"We already know that as you add CO2 to the atmosphere and the global mean temperature rises, the wind circulation changes as well - and in less obvious ways.
The study, published in the journal Nature Climate Change, analysed return flights from Hawaii to Los Angeles, San Francisco and Seattle by four different airlines. They found that when an eastbound flight became 10 minutes shorter, the corresponding westbound flight became 11 minutes longer.
Pull that cork and see what happens!
Aside from a few obscure Russian sites, the only pages a google search turns up for "Korkinass" are versions of this article.
That doesn't inspire confidence in the existence of this person or his friends, Oliver Klozoff, I.P. Freeley, Maya Normusbutt or Heywood Jablome.
Long flights — they never stop creating new fears.
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Headwinds add more time to your upwind leg than you gain with the same tailwind on the return (downwind) leg.
Yeah... on Mars.
Come ON! You don’t expect us to believe any real person is named Korkinass? They say the truth can be stranger than fiction, but that beats ‘em all!
Korkinass. That’s the Old German name.
It translates to Analretentive.
Doesn’t this entire ‘study’ presume that aircraft are flying at full throttle ALL THE TIME?
Don’t the pilots just punch in a speed, and relax. If there a discrepancy of a minute, its more likely due to some turning movement required leaving the airport, etc.
Lies, lies, and more lies.
They appear to assume that fuel consumption for a given airline route with an airplane is constant over time, which it isn’t.
The main reason is, jet engine technology is improving all the time, and newer high-bypass turbines have MUCH better economy than engines of previous generations, sometimes 25 percent better for the same thrust (not to mention they’re quieter).
Another reason is, computer wind modeling is much better, and the uploading of those winds happen real-time over SATCOM, enabling modern technology-equipped airliners to much better select altitudes and routes for wind optimization, reducing fuel consumption and flight times. Only a few years ago the infrastructure wasn’t there to do this. Pilots reported their positions over scratchy HF radios and there was no wind uploading, and few airplanes had flight computers that could handle wind optimization anyway. They had simple INS’s for navigation (the DC-10 for example).
Only a few years ago most transcontinental airliners had three or four engines; now because of reliability increases with more modern engines, ETOPS rules for extended overwater operation have allowed for competing two-engine aircraft to dominate the market, because of their increased fuel economy (thus increasing the competitiveness of the two-engine configuration airplanes, such as the 777). Two engines have lower maintenance costs that four. Observe how badly the A380 (four engines) is doing in the market — they’re about to shut down production. It’s too big for too many airports, and not competitive enough for enough routes, partly because of it’s four-engine design.
Flight times don’t necessarily equate with fuel consumption. It’s better to fly slower with a tailwind, closer to best endurance speed. The longer you can take advantage of the tailwind, the more of a “free ride” you get from the winds. Into a headwind, you fly faster, but fuel economy quickly diminishes, so you pick a different route or different altitude. That’s why the NAT tracks across the North Atlantic (set routes for airliners) tend to be at one latitude for eastbound, and a different latitude (north or south) for the other direction. Or you pick an optimized random routing, with altitudes and circuitous routes picked by a computer with knowledge of temperatures and altitudes at all waypoints. So you seldom fly the exact same route into the wind from point B to A as you did with the tailwind from A to B.
The point is, this article seems to be equating flight times directly to overall fuel consumption without publishing the actual fuel consumption data, a dishonest practice intended to mislead their readers and the public.
How they eliminated the variables in this study must have been a wonder to behold. They would have had to assume that both legs of the flight left at the same time of day, encountered the same wind speeds at all different times of the journey, they must have had available the exact - to the second - time of lift off and wheels touchdown, flown exactly the same flight paths, encountered exactly the same stacking, carried exactly the same fuel loads etc etc etc.
It would be very interesting to see their data and methodology.
westerly winds have existed for ever
Test flights were made by an Asiana flight crew consisting of Captain Sum Ting Wong, Wi Tu Lo, Ho Lee Fuk, and Bang Ding Ow.
Seriously, a headwind WILL increase the round trip time. It is because the plane will fly for a longer period of time fighting a headwind than the time it will have with a tailwind.
That approach has long since been left behind. If it validates "globull warming", then it has to be taken on faith without questioning.
I get the distinct impression that all these "studies" are coming out suspiciously close to the meeting of the congregation of the faithful in Paris in September adding to the "overwhelming evidence". Luckily the heathen Australians are going to be there to p*ss in their Punch bowl.
Seems to me that higher speed wings from west to east would increase east to west flying time but decrease west to east flying time by the same amount. It has always taken longer to fly NYC to LA than LA to NYC. It did in the late 1950s when I worked for the airlines and I don’t believe globull warming has changed the fact.
“Stronger winds mean longer flight times one direction but shorter flights the opposite.”
Actually, if you do the math, you’d find that having winds in one direction will shorten the flight in that direction - say taking it from 10 hours to 9 hours. But if you go the other way with the same wind, the flight time will increase a bit more, from 10 hours to 11.5 hours. So the round trip time is a bit longer.
On the other hand, for long flights where there is a choice of directions (such as halfway around the world)...then a strong wind actually helps all around as you can, for example, go west from NYC to Australia, but instead of back-tracking, you continue to go west from Australia to NYC...so you get a tailwind in BOTH directions - so a stronger (tail) wind helps out overall.
If the hypothesis is true then east to west flights would be slightly longer however west to east flights would be slightly shorter. No problem.
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