For a minute there I thought I had to get off my couch, when all the while the fact is we don't have to do anything much but keep things afloat for just a few decades more! In fact, we'd best shut up about PO, because if our offspring finds out we knew about it all along, they'll turn and wring our necks come 2036!
Posted: Wed May 02, 2007 6:45 pm Post subject: Re: Aviation Fuel price record
Avgas, also known as 100LL is close to gasoline. 100 octane, more or less, boosted with a little good-old-fashioned tetraethyl lead. Basically, what you'd get as high-test gasoline in the 1950s, or still gets driven at a NASCAR track. Avgas is used in piston-propeller aircraft only, not jets, not even your regional turboprop. Avgas tracks gasoline, but is only made by a few refineries. The market is small compared to conventional unleaded, and the distribution system is necessarily much more inefficient.
Joined: Apr 05, 2005 Posts: 2395 Location: South of Atlanta
Posted: Wed May 02, 2007 7:51 pm Post subject: Re: Aviation Fuel price record
Lawnchair is correct. Avgas is strictly used for piston/propeller engined aircraft. The general aviation fleet is not a giant consumer but it does have an effect on the economy when cost goes up for avgas.
I added it as another measire of how PO is going to affect us.
Jet fuel is basically kerosene, also referred to as JP-4 by the military. Its used for all jet powered aircraft and turboprops. The hard thing to nail down with jet fuel and the airline market is hedging. Most of the airlines do it or have done it recently. The legacy airlines have had a lot of trouble hedging due to cost as of late. At the monet the amount airlines are hedging is a small amount of the total fuel used.
Joined: Apr 05, 2005 Posts: 2395 Location: South of Atlanta
Posted: Mon May 07, 2007 12:02 pm Post subject: Re: Aviation Fuel price record
This link to PDF ha some very good graphs showing consumption/price/ and crack spread info. The trends dont look good when historically measured. It's interesting to note most of the stuff in here thats PREDICTED doesnt look so bad. A bit of pandering maybe?
Posted: Thu May 10, 2007 12:40 pm Post subject: Re: Aviation Fuel price record
dohboi wrote:
Perhaps our science teacher or others espousing the efficiency of airtravel could let us know what energy is expended lifting mass 35,000 feet? Or accelerating rapidly to 600mph?
And don't forget that for millennia people have been traveling by boat using wind power (and of course good ol' slave power when the breeze dies down ).
The answer is "not enough to alter the great advantage of efficiency in moving people by aircraft". An airliner flies a long way at the end of its flight just gliding on the height and speed built up earlier, so you get most of it back.
Ship resistence at high speed is actually due mostly to the ship trying to lift itself onto its own wake. This is because the wavelength of the wake increases as the ship gets faster, until the stern drops into the trough of the wave. This creates enormous resistance, since a component of the ship's weight is now against it, rather than resting in the water.
Although you are right that people have sailed for millennia, it was only in the last 150 years that any scale of long distance travel has been possible, due to steam ships. This is what Brunel was pioneering. Sailing ships (almost) never carried more than a handful of wealthy passengers as the icing on top of the cargo trade. Until the last 30 years, long distance travel was a once or twice in a life time experience for all but the top of the middle class and the upper class. Only with cheap air travel as pioneered by Laker in the mid 1970s has regular long distance travel been affordable for "the masses". This world of easy mass travel has developed amazingly quickly. It would be quite spectacular if it disappeared even more quickly, I must say.
The proof of the pudding will be the disappearance of the cruise liner market when oil prices go through the roof. Cruise liners are definitely a "nice to have", not a "must have".
Joined: Apr 05, 2005 Posts: 2395 Location: South of Atlanta
Posted: Fri May 11, 2007 7:20 am Post subject: Re: Aviation Fuel price record
Avgas is up to a national average of 4.25 gal. Since this is really a "boutique" fuel I'm kind of surprised by the rise. Usually refineries only do runs of this on an infrequent basis. I wonder If the concentration on gasoline will cause this to rise disproportionally over time. Usually this fuel trends similar to gasoline, but doesnt move as much up and down.
Jet fuel is actually down slightly to 2.08 a gallon national average. once the summer schedules crank up in June, I expect a spike in this price. As gasoline gets uglier I expect a larger premium on the crack spread due to that.
Jet Blue's CEO David Neelman proposed a huge government program subsidizing many plants to do just this late last year, but so far I haven't heard anything come of it yet. His plan was announced some time last year. I believe presently the cost of the plants is the sticky issue.
It is very interesting to note at the bottom of the article above, the author falls into the common trap of saying there are "hundreds" of years of coal..............."AT PRESENT RATES OF CONSUMPTION".
I guess they think once we start doing all this magical stuff with coal that number isn't going to change. How totally ignorant and blissfully cornucopian!
Posted: Fri May 11, 2007 9:51 am Post subject: Re: Aviation Fuel price record
malcomatic_51 wrote:
The answer is "not enough to alter the great advantage of efficiency in moving people by aircraft". An airliner flies a long way at the end of its flight just gliding on the height and speed built up earlier, so you get most of it back.
I don't think thats correct. With a glide ratio of somewhere near 17:1 and a cruising altitude of say 30,000ft a modern airliner would only be able to glide maybe 100 miles (and turns will cause you to lose altitude even faster). That would not qualify as getting "Most of it back" .
malcomatic_51 wrote:
Although you are right that people have sailed for millennia, it was only in the last 150 years that any scale of long distance travel has been possible,
I see no reason why large scale sailing is not possible. And a large portion of those who sailed back and forth on the Atlantic were hardly what I'd call rich. It was cheap enough that England even exported criminals to Australia and America. As well as refugees and indentured servants.
-G _________________ All right, you primitive screw-heads, listen up!
Joined: Apr 05, 2005 Posts: 1619 Location: Springsteen Country (NJ)
Posted: Fri May 11, 2007 1:36 pm Post subject: Re: Aviation Fuel price record
AirlinePilot wrote:
It is very interesting to note at the bottom of the article above, the author falls into the common trap of saying there are "hundreds" of years of coal..............."AT PRESENT RATES OF CONSUMPTION".
I guess they think once we start doing all this magical stuff with coal that number isn't going to change. How totally ignorant and blissfully cornucopian!
Here's a handy, dandy calculator that can tell you how much it will change.
http://peakhumanity.com/resourcecalculator.php _________________ Joe P. United Political Debate
"Only when the last tree is cut; only when the last river is polluted; only when the last fish is caught; only then will they realize that you cannot eat money." - Cree Indian Proverb
Joined: Apr 28, 2005 Posts: 3431 Location: West shore Lake Eire, MI, USA
Posted: Fri May 11, 2007 7:36 pm Post subject: Re: Aviation Fuel price record
Hey AP, IIRC E-85 has a very high octane rating and is sold at a subsidized price, how hard would it be for a decent aircraft engine mechanic to switch an engine over to use it? You won't get the same power to weight ratio, but if you save over a buck per gallon it might be worth it, and the engine would still be able to burn Avgas. _________________ Oxygen: - An intensely habit-forming accumulative toxic substance. As little
as one breath is known to produce a life-long addiction to the gas, which addiction invariably ends in death.--Isaac Asimov
Joined: Apr 05, 2005 Posts: 2395 Location: South of Atlanta
Posted: Fri May 11, 2007 8:00 pm Post subject: Re: Aviation Fuel price record
Well first you would have to get the FAA and the aircraft manufacturere to ok it. Basically you and or a mechanic and some other folks test it for the manufacturer. With the proper documentation and review by the FAA its possible, but it would take a while and a good bit of resources to do it. My Cessna 150 can burn auto fuel right now. Not all aircraft are certified to do that.
Joined: Apr 28, 2005 Posts: 3431 Location: West shore Lake Eire, MI, USA
Posted: Fri May 11, 2007 8:01 pm Post subject: Re: Aviation Fuel price record
Found some AVE-85 info on Wikipedia,
Quote:
E85 has been repeatedly shown to produce more power than a comparable gasoline fuel, especially in engines that need high octane fuels to avoid early detonation.[3] Ford Motor Company found that power typically increased approximately 5% with the switch to E85 [4]. Researchers working on the equivalent of E85 fuel for general aviation aircraft AGE-85 have seen the same results with an aircraft engine jumping from 600 hp on conventional 100LL AV gas to 650 hp on the AGE-85. Recorded power increases range from 5% to 9% depending on the engine. [5][6]E85 Wiki
_________________ Oxygen: - An intensely habit-forming accumulative toxic substance. As little
as one breath is known to produce a life-long addiction to the gas, which addiction invariably ends in death.--Isaac Asimov
Posted: Sun May 13, 2007 7:41 pm Post subject: Re: Aviation Fuel price record
Malcomatic wrote:
"Although you are right that people have sailed for millennia, it was only in the last 150 years that any scale of long distance travel has been possible, due to steam ships. This is what Brunel was pioneering. Sailing ships (almost) never carried more than a handful of wealthy passengers as the icing on top of the cargo trade."
Hmmm. Ever heard of the Vikings? How do suppose the Pacific islands were populated?
"Until the last 30 years, long distance travel was a once or twice in a life time experience for all but the top of the middle class and the upper class. Only with cheap air travel as pioneered by Laker in the mid 1970s has regular long distance travel been affordable for "the masses". This world of easy mass travel has developed amazingly quickly. It would be quite spectacular if it disappeared even more quickly, I must say."
Good point here. I'm afraid I lost the source, but as late as 1970, only some 10% of Americans had ever flown. You are still wrong about the efficiency of air travel (you have not addressed the enormous drag at 600mph even at high altitudes, given drag's nonlinear relationship to speed).
But the main point is exactly the one you infer here: Even if air travel were equal to or slightly more efficient than other forms of travel (which it is not), the fact that it makes long distance travel so easy, fast and cheap means that more people are more likely to go further more often than if this option were not available. There is no possiblity of a livable future with most people taking multiple long distance trips of any sort, unless we all become as daring and gifted as the Vikings and Pacific islanders.
George Monbiot, though, has concluded in a recent article that dirigible flight may be one form of flight that could be sustainable (though it is hardly rapid).
Posted: Sun May 13, 2007 9:19 pm Post subject: Re: Aviation Fuel price record
dohboi wrote:
You are still wrong about the efficiency of air travel (you have not addressed the enormous drag at 600mph even at high altitudes, given drag's nonlinear relationship to speed).
Was there really a need to address it? We know the passengers carried, distance traversed, and the fuel consumed. Those are the only relevant numbers. And, for lightweight but bulky cargo (people), especially cargo that gets bulkier the longer the voyage takes (sleeping quarters, food, fresh water), flying is more efficient than fossil-fueled ships.
Sailing, is of course, a different matter. But, well under 1% of people ever sailed pre-steam, and for most of them it was a one-way never-to-return trip. Quite regularly also a never-to-make-it-there trip.
Posted: Mon May 14, 2007 1:12 pm Post subject: Re: Aviation Fuel price record
Even after allowing for food etc., if we reverted to the liners ala pre world war II style with limited space per passenger etc. air travel will not be more efficient. Water can be gained by using waste engine heat for desalination so no need to carry that around. Ships can also utilize much more efficient powerplant configurations like combined cycle diesel/steam or fuel cell/turbine etc. and may even be able to use wind, solar sails to advantage. _________________ For ionizing radiation “…the human epidemiological evidence establishes—by any reasonable standard of proof—that there is no safe dose or dose-rate…the safe-dose hypothesis is not merely implausible—it is disproven.” Dr. J.W. Gofman 4
Joined: Apr 05, 2005 Posts: 2395 Location: South of Atlanta
Posted: Mon May 14, 2007 9:32 pm Post subject: Re: Aviation Fuel price record
Avgas up to 4.26. jet fuel basically unchanged. Doesnt seem to be mirroring regular crude or gasoline for now. I am actually quite surprised at how stable Jet Fuel is. Avgas i can understand becuase its very similar if not almost identical to auto gas in many cases, just a slightly higher octane.
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