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-   -   Pollution by Big Jets - curious (https://www.pprune.org/questions/162954-pollution-big-jets-curious.html)

eden 11th Feb 2005 14:38

Pollution by Big Jets - curious
 
Please help.
I am interested to know where I might find out .... the precise truth about the pollution caused by Jet aircraft? I'd just like to know where to look for some pukka figures and maybe some comparisons to things such as car traffic and other industrial polluters. Thanks in anticipation

gashcan 11th Feb 2005 14:47

I always find it a bit sobering to think that the 50 tonnes or so that a 330 will drink on a pond-crossing will keep an average family car going for about 25 years.

(Give or take a bit - calculation done very very roughly on the back of a fag packet - I expect that there are many far cleverer than me who could come up with something more accurate with regard to fuel burn and CO output etc - I just like the family car simile!)

brabazon 11th Feb 2005 15:57

Try starting from the ICAO engine emissions databank which can be sourced through the UK CAA:

http://search2.openobjects.com/kbrok...ne%20emissions

GreatMe 11th Feb 2005 16:07

The big problem with the pollution caused by jets is less to do with how much pollution is released relative to things like cars and industry, but rather where it is released. This is because the atmosphere is far less active (and wet) at high altitude and so the pollution, especially the particulates and water soluble compounds such as sulphur dioxide that are usually removed by rain, stay there far longer.

The particulates help nucleate high altitude ice formation and so reduces the amount of sunlight reaching the earth. This could be seen after 9/11, when temperatures across the US rose by a couple of degrees. Strangely, this means that in the short term aircraft slow global warming, but increase it in the long term through carbon dioxide emmisions.

cortilla 11th Feb 2005 16:54

i can't remember the exact link but there is a paper written by HM treasury called 'Aviation and the environment using economic instruments' written in 2003 together with the department for transport. Has quite a bit of data in it. There's also a section in the aviation white paper on the environment. If you're looking for anything specific pm me. I've written a few papers around the subject (although not specifically on pollution but i do look at it a few times).

There was a programme about global dimming a few weeks ago on channel four, the topic Greatme talks about.

FlightDetent 11th Feb 2005 18:28

Some info may certainly be derived from here .

Cheers,
FD

Piltdown Man 11th Feb 2005 20:28

Roughly two tons of CO2 for every ton of fuel burnt - the same as a car! (or steam engine, diesel etc...). However, to achieve the same fuel economy as a car, you would have to run around with at least five people (and the modern jet does this as 500 MPH). When motorised transport is considered, ships are probably the most efficient, followed by trains, then us and along way behind, you family car.

And we also have to be careful about the the type of polution generated. All transport generates polution. Bicycles generate poo! Aircraft generate the same polutants as all other fossil burners but with the difference in so much that we dump it out at altitude. Apparently this has an effect as discussed earlier. And don't foget that an electric train can be run by nuclear energy!

It all depends what you want to prove and who pays for the research because I'm sure that anything could be proved.

bealine 12th Feb 2005 07:54


Cortilla Wrote:- i can't remember the exact link but there is a paper written by HM treasury called 'Aviation and the environment using economic instruments' written in 2003 together with the department for transport.
Link Here

(It is in Adobe Acrobat Reader .pdf format but if you haven't got it, you can download Acrobat Reader free from here

eden 12th Feb 2005 14:59

Hey - thanks for the responses, much appreciated.

It gives me plenty to look into - All the best!

Salty123 13th Feb 2005 00:50

One more thing to add are VOCs, a main cause of smog. The fuel used in aircraft is lighter than that used for a car and thus evaporates at a higher rate. These vapours (known as a type of Volatile Organic Compound) react with NOx compounds to create ground level ozone, a main component of smog (cars do the same but fuel is not as volatile). Not sure what the burn efficiency is low level, but it certainly doesn't help wrt pollution.

Add on to this the CO2 created at altitude being a contributor to Enhanced Greenhouse Effect, aviation causes pollution at several levels. Let's not even go into fuel dumping.

Sorry 'bout the chem mumbo-jumbo. Just wrote a paper and exam on it.

palgia 13th Feb 2005 06:49

Salty123


One more thing to add are VOCs, a main cause of smog. The fuel used in aircraft is lighter than that used for a car and thus evaporates at a higher rate. These vapours (known as a type of Volatile Organic Compound) react with NOx compounds to create ground level ozone, a main component of smog (cars do the same but fuel is not as volatile).
Are you sure that the "fuel used in aircraft" (Jetfuel) is more volatile that automotive gas??? ::\

Did you already hand in that paper/exam??? :uhoh:

palgia

one dot right 13th Feb 2005 07:34


Roughly 2 tons of CO2 for every ton of fuel burnt
Eh? Sounds like magic to me,or am I missing something?

aerolearner 13th Feb 2005 08:55


Eh? Sounds like magic to me,or am I missing something?
You pay for the C in the fuel, but you get O2 free of charge from the air.

one dot right 13th Feb 2005 09:09

Thanks for clarifying that for me!

bealine 13th Feb 2005 12:23


but you get O2 free of charge from the air.
Don't let the government know - they'll want to tax it!:p

404 Titan 13th Feb 2005 13:25

I always love this little debate about aircraft pollution. The reality is that if you took one A330 with 300 pax and 75 cars with 4 pax each, and made them travel 9000 km, who do you think will burn more fuel. The A330 is going to take about 9.5 hrs to travel the 9000 km. At about 6 tonnes an hour it will burn 57 tonnes or 72900 ltrs of fuel. The 75 cars will each burn on average 1 ltr of fuel per 7 km's. Therefore over the 9000 km's each car will burn about 1285 ltrs of fuel or 96375 ltrs between the lot of them. This makes the cars 32% less efficient over the same distance or 32% more polluting than the A330.

ManAtTheBack 13th Feb 2005 16:31

Eden

You might like to read "Towards Sustainable Aviation" edited by Paul Upham, Janet Maugham, David Raper and Callum Thomas for a varied selection of views of aviation's effects on the environment, including emissions, noise and health.

palgia 14th Feb 2005 05:53


but you get O2 free of charge from the air.
and


Don't let the government know - they'll want to tax it!

They DO know and they ARE taxing it!!!:{
Thats what you are paying with every gallon of fuel;)
And what corporations (should) pay when polluting the atmosphere:ugh:
The problem is that the price is still too cheap...


palgia


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