Aircraft Pollution

[G-Foxtrot Oscar 69]

I recently had a discussion with someone about aviations contribution to global pollution.

It was down the lines of aircraft are big and burn loads of fuel so create lots of pollution!

I was trying to agrue about the gas turbine being extremly efficent and clean. I also tried to argue about the fact that fuel costs money and is heavy so the aim is to squeeze every last joule of energy out of the combustion.

My best tech lecture was not to be taken.

Can any one give me some hard facts and figures I can quote to defend aviation, or to prove me wrong!

I am not talking about noise pollution but chemical.

Thanks for your help.

[GlueBall]

Whatever those figures may be; for a comparative reality check: When Mt. St Helen blew its top in...1980(?) it spewed more carbon dioxide into the atmosphere than all the CO2 from the exhausts of all the World's automobiles in the past 100 years.

[Trash Hauler]

As aircraft spend most of their time above the environment any polution effect can be discounted....................TIC

On a serious note aircraft in the US consume approximately 5% of the total fuel used by the nation. While not an accurate indicator in CO2 terms this equates to 5% emitted.

Cheers

[Hay Ewe]

I think you will find that flying is, excluding solar power, the most efficient form of transport.

The fuel consumed to move 300 people across the atlantic by 767 is much less than a boat or equivilent distance by car. Of course the number of people on the airplane would affect this but then they carry less fuel due less weight.

And then point out the number of cars occupied by a single person in the M25 or your local stretch of traffic jam, all with the engines running and big engines at that and aircraft pale into insignificance!!

And then when they say, ahh, the electric car, you can counter with, "and where does the electricty come from to charge the batteries?" and when they say about fossil fueled power stations, suggest Nuclear, they are clean and have minimal pollution except when it goes wrong. How many times have there been major accidents over the whole time they have been producing commercial electricty?

Last year in Australia was highlighted because per capita it produces more gas pollution than any other developed country, the simple reason is that Australia only has a population of around 20 million, and the amount of smelting and conversion form raw to refined materials that occurs, per capita it isnt so good.

remember there are Statistics, damn statistics and Lies, back it up with good arguments and youcan get most of the greenies to back down.

Enjoy, Hay Ewe

[G-Foxtrot Oscar 69]

Thanks to all who have posted. I have cycled all the arguments about cars etc. I even tried to apply some school chemistry to bond energies ie Breaking and Making bongs in Petrol Vs Jet A1. But hey greenines are not interested in hard science but like Hay Ewe said stats damb stats.

I also used the Bus is more efficent than a car as it carries more peole etc etc etc. Then there was the argument but of course aircraft pollute more they go faster. Try giving a lecture on fluid dynamics to a tree hugger

I will try showing said offender your replies. If all else fails I suposed I could always brand "SAY YES TO A SECOND RUMWAY AT BIRMINGHAM" on said offender

[Noise Unit]

Now I am not an expert, but do have an opinion.

While I agree with much of what has been said above, I believe that the main reason that commercial aviation has been under pressure is that the environmental impact per unit weight of fuel used is greater.

This is because much of the aircraft exhaust gases are placed directly into stratosphere. This means that it stays there for a long time (measured in 10s of years I believe; it could be as long as 100 years) as there is little mixing of air layers. The CO2 and Nox are also placed closer to the Ozone layer. The high altitude cirrus and contrails formed by water vapour in the exhaust are another concern for the 'greenhouse effect'.

I'm interested to hear further views on this and learn some more

[HotDog]

Now I am not an expert, but do have an opinion.

Nor am I but in all my flying hours in commercial aircraft, we never managed to get out of the Troposphere. U2, Concorde and Blackbird may support your argument to a small degree, certainly enough to convince the Greenies and the Chemtrailers and yourself.

[Noise Unit]

I too have seen some places defining the start of the stratosphere as 20km (66kft), but my understanding of the ISA is that the stratosphere starts at the tropopause (11km or 36089ft), and this gets lower and high latitudes.

Don't believe the word of a pom? Try the following Australian link

http://www.ae.su.oz.au/aero/atmos/atmos.html

[G-Foxtrot Oscar 69]

Noise Unit, that is a really handy link. Beats giving the text books a bashing. It will contain the answer to another question I have been mooting.

Thanks