[AirlinePilot]

$this->bbcode_second_pass_quote('Tanada', 'N')ew questions for AP

I have been watching a series of lectures on AGW and the section on contrails caught my attention. You are the obvious person to ask about them so here we go.

What is the highest practical cruising altitude for the commercial passenger jets you are rated to fly? Cargo jets too if any are applicable.

Is it true that Contrails rarely form above flight level 390 and are very rare above 450?

If not what level does the formation of contrails start to fall off at and what aircraft can cruise at those levels?

I know that when a jet takes off at max weight it has a hard time reaching a high flight level, but I am given to understand that within two hours enough fuel is consumed to remove this limit. Is that a good rule of thumb or am I misunderstanding something about the physics of flight?

How much extra fuel does a commercial aircraft burn at say FL430 vs FL 350?

Other questions will depend on the answers to these so I will eagerly await your answers.

[Tanada]

$this->bbcode_second_pass_quote('AirlinePilot', '
')An aircraft's altitude capability is determined by its aerodynamics(wing), thrust available, and fuel/passenger/cargo load. Two hours is NOT a good rule of thumb to use as far as being able to continue a climb after weight is burned off due to fuel consumption.

[AirlinePilot]

There really isnt any rule of thumb. Some aircraft can fly up to their design cieling limits at full weights. I'd say that for most aircraft before they travel half the distance of any longer range route, they are capable of climbing to their maximum altitude. Probably a pretty safe bet, but Im basing this on assumption really and my experience.

[TheDude]

passenger plane contrail global warming - Google Scholar

Here are some interesting quotes from "Transport and climate change: a review":

$this->bbcode_second_pass_quote('', 'I')n addition to passenger aircraft, approximately 18% of aircraft
are military where performance requirements ensure
that they will produce significantly more emissions (RCEP,
2002).

[NeedsBetterName]

I've always assumed that when contrails hang around for a long time, the air above my head is moist, and if the contrails disappear quickly, the air is dry.

I would assume a "flying wing" type aircraft would be more efficient then current designs?

Air travel is going away for most of us, so i doubt much will be spent on new designs. I would think they'll just cram ever more amounts of humans on each flight.

[Graeme]

Can Flying Ever Be Green?

$this->bbcode_second_pass_quote('', 'C')an the aviation industry ever be sustainable? Aviation may only be responsible for 2 percent of global CO2 output,1 but that’s 13 percent of the world’s transportation fuels each year,2 or 670 tonnes (metric tons) of CO2 annually.3 It would take roughly 23,680,000 trees planted per month to offset all the aviation carbon produced each year.4 The International Civil Aviation Organization (ICAO) predicts that aviation will continue to grow globally by 5.6 percent per year through 2024, but the urgency in finding a solution is even more apparent when we consider the Centre for Asia Pacific Aviation’s projections for passenger growth in India and China over the next 20 years. Less than 2 percent of Indians fly domestically each year. This is forecast to increase sevenfold in the next 20 years. China’s domestic air traffic is five times that of India’s, with a fivefold increase predicted in 20 years. Such figures are alarming, yet their contribution to greenhouse gas emissions comprises only a fraction of global output. To have any marked greenhouse gas reduction, developed nations must lead the way.

There are no simple answers for achieving the International Air Transportation Association’s (IATA) target of carbon-neutral growth by 2025, but the introduction of more fuel-efficient aircraft, the balanced implementation of a global emissions trading scheme, the development of alternative fuel sources, and the upgrading of air traffic control through more efficient air traffic management procedures could be major steps toward a more ecofriendly sky.

[Pretorian]

sorry for oof top, which trees they supposed to be planting? Bamboo? Something with a crazy growth?

[scas]

Airlines are always teetering on the verge of bankruptcy. Peak oil will see the reduction in volume of air travel long before other industries collapse. What will remain is travel only for the elite, much like in the early years of aviation.

I spent 6 years flying commercially, and the amount of fuel and infrastructure required for a cattle-class transportation industry is just incredible. It's a bubble industry, like any other.

Reduction will come in two ways - an inability of governments to prop up airlines, and the inability of people to afford air travel anymore.

ransportation Association’s (IATA) target of carbon-neutral growth by 2025, but the introduction of more fuel-efficient aircraft, the balanced implementation of a global emissions trading scheme, the development of alternative fuel sources, This is feel good garbage that achieves nothing. Perhaps it may raise costs so that people fly less.

[KingM]

I don't think the airline model works. One year they lose billions, the next they make billions. They require massive subsidies in the form of air infrastructure and rely on fossil fuel. I could conceive of a future where people flew using some sort of biofuel while all other transportation had been converted to electric, but this is a future where air travel is a niche luxury, as it was several decades ago.

I could be wrong, but this is the optimistic view of the future. The pessimistic view is that people sitting around camp fires in two or three hundred years will hear stories about flying metal tubes and scoff.

[Revi]

I don't know if it can ever be "green", but it could be done in a way that uses a lot less oil. Boeing is coming out with a plane that uses signifigantly less.

Why not use it for what it's good for and put people on high speed rail for intercity travel?

It seems like the way we are doing airlines now won't make it, but maybe a stripped down plane might be able to fly across the Atlantic or the Pacific for a while longer.

[dinopello]

$this->bbcode_second_pass_quote('Graeme', '[')b]Can Flying Ever Be Green?

[jmnemonic]

I was thinking dirigibles might make a comeback. Much slower, but more fuel-efficient. I could even see building them out of some solar-absorbent material and running electric engines. For things that could be shipped slowly, I don't see why that couldn't be done. If a thousand refrigerators take three months to cross the ocean, who cares? Just extend the supply lines. Ditto sailboats on making a comeback for sea travel.

[hillsidedigger]

I suppose a limted amount of jet fuel could be produced from biomass.

[Ferretlover]

Hawker Beechcraft will be acquired by China's Superior Aviation
By KSNW News, KSNW-TV, updated 7/9/2012 7:51:43 PM ET
$this->bbcode_second_pass_quote('', 'W')ICHITA, Kansas — Hawker Beechcraft announced Monday that Superior Aviation Beijing Co. will acquire the company for $1.79 billion.
Should the sale be complete, Superior intends to maintain Hawker Beechcraft's existing operations while also investing substantial capital in the company, and its business and general aviation product line.
The transaction with Superior would not include Hawker Beechcraft Defense Company, which would remain a separate entity.
"Superior has had a long-standing interest in the commercial aircraft business of Hawker Beechcraft, having first approached the company several years ago regarding a potential strategic partnership. With Superior's previous experience operating a U.S. business and its demonstrated ability to quickly restore a business to profitability after emerging from Chapter 11, we believe a transaction with Superior would maximize value for Hawker Beechcraft and its stakeholders," said Robert Miller, Hawker Beechcraft CEO. "Importantly, this combination would give Hawker Beechcraft greater access to the Chinese business and general aviation marketplace*, which is forecast to grow more than 10 percent a year for the next 10-15 years. We look forward to working toward a definitive agreement."

[Timo]

That's Gov. Brownback, for you, selling homegrown and successful staple industries to the Chinese. He's following the Romney model to at T, only the venture capital is public interest, not his own private company. Distract the public's atention with inane, trivial, but hyper-emotional issues. Use those issues to get elected, and then wreak havoc over the public's best interest, all in the name of personal profit. That's the American Way!

[Ferretlover]

We can be sure that it is Mittwit's way. Kansas is about as Republican as it can be, and when it comes to politics, its citizen wear the biggest blinders you can imagine!

[Tanada]

$this->bbcode_second_pass_quote('KingM', 'I') don't think the airline model works. One year they lose billions, the next they make billions. They require massive subsidies in the form of air infrastructure and rely on fossil fuel. I could conceive of a future where people flew using some sort of biofuel while all other transportation had been converted to electric, but this is a future where air travel is a niche luxury, as it was several decades ago.

I could be wrong, but this is the optimistic view of the future. The pessimistic view is that people sitting around camp fires in two or three hundred years will hear stories about flying metal tubes and scoff.

[Keith_McClary]

$this->bbcode_second_pass_quote('Tanada', 't')hey fill up with thousands of gallons of Kerosene which they do not pay a fuel tax on.

[Tanada]

$this->bbcode_second_pass_quote('Keith_McClary', '')$this->bbcode_second_pass_quote('Tanada', 't')hey fill up with thousands of gallons of Kerosene which they do not pay a fuel tax on.