Talk:Environmental effects of aviation/Archive 1

Simple solution
I can think of a very simple solution not mentioned in the Possible Reduction section.

Don't fly.

I can't be the only one to think of it, why isn't it mentioned?

195.26.62.238 (talk) 06:55, 31 May 2008 (UTC)


 * Find a verifiable reference for that and it can be added! - Ahunt (talk) 11:26, 31 May 2008 (UTC)


 * Plenty of info on this over at Air transport and the environment (United Kingdom). It's an oft quoted remedy by environmentalist campaign groups, but the best source I have come across is the study UK specific, but the principles of using economic instruments to restrict the demand for air travel and thus reduce environmental impacts are pretty much universal I think. --FactotEm (talk) 11:57, 31 May 2008 (UTC)


 * That is a very interesting reference. I have written a new section "Government-imposed reductions in aviation" using it as a ref. See what you think - feel free to expand it. - Ahunt (talk) 18:46, 31 May 2008 (UTC)


 * Having dragged that article unsuccessfully through FAC 3 times, I'm having a bit of a rest from aviation environment related articles for the moment. I would say though that "Government-imposed" reductions is a mis-nomer. In actual fact the UK Govt supports expansion to cater for increased demand. A better title might be "Managing demand".


 * I don't recall whether the paper actually supports the idea that the aviation industry "must be forced by taxation to greatly shrink in size and significantly reduce the number of aircraft operated and passengers flown". The House of Commons Environmental Select Committee supported restricting air transport so that emissions don't rise in absolute terms (i.e. growth is only permitted in line with reduced emissions resulting from fuel efficiencies). The campaign group AEF support increased taxation that is predicted to permit growth but limit it to 2% p.a.


 * Finally, I think you would get the point across more succinctly if you limited the quote you have selected to "Making flying more expensive, by introducing new taxes or charges, offers one of the quickest ways to address the demand for air travel." and finding a way of saying "and thus reducing the impact on the environment". I find the stats bandied around about future demand on the carbon budget by the air transport industry inherently POV, but that's just my opinion. --FactotEm (talk) 19:42, 31 May 2008 (UTC)

It's probably easier if you just go ahead and edit it! - Ahunt (talk) 19:52, 31 May 2008 (UTC)


 * Damn! Didn't fall for my FAC trauma sob story then. --FactotEm (talk) 20:38, 31 May 2008 (UTC)

I like the re-write - it looks good! - Ahunt (talk) 12:39, 1 June 2008 (UTC)

Peripheral effects paragraph
There have been two attempts to remove the paragraph that says:

"In addition to the CO2 released by most aircraft in flight through the burning of fuels such as Jet-A (turbine aircraft) or Avgas (piston aircraft), the aviation industry also contributes greenhouse gas emissions from ground airport vehicles and those used by passengers and staff to access airports, as well as through emissions generated by the production of energy used in airport buildings, the manufacture of aircraft and the construction of airport infrastructure."

with edit summaries "Not clear how this fits in" and "This is not related to aviation per se, and is beyond the scope of this article"

I personally can't see that those comments make sense as the paragraph is clearly discussing how facets of the aviation industry, other than actual flying operations, also damage the environment. The paragraph still needs a reference added but otherwise I can see no argument presented for removing it. - Ahunt (talk) 11:51, 15 July 2009 (UTC)

Non-sentence in section "Potential reductions"
"While ethanol also releases CO2 during combustion, the plants cultivated to make it draw that same CO2 out of the atmosphere while they are growing, making the fuel closer to climate-change-neutral." -Pgan002 (talk) 22:19, 27 July 2009 (UTC)

Alternate Fuels section neutrality tagging
I agree that this section could use some balance, but other than research projects that have not quantified costs or sustainability (see Avgas for some of these) at present I haven't found any refs that could be used. - Ahunt (talk) 14:27, 3 February 2011 (UTC)
 * Okay I added some text and refs on avgas biofuel, what else needs to be done to make this section more neutral? - Ahunt (talk) 15:32, 3 February 2011 (UTC)
 * I've removed some material that was about the general biofuels debate and which didn't mention aviation and have replaced it with something more relevant. Have removed tag. Johnfos (talk) 20:45, 3 February 2011 (UTC)

I have moved the "see also" addition (referring to the Sustainable Biofuels page) to this section to the existing "See Also" section. Also, I believe the Johnfos unjustly removed content because it fit the context; however, I will add some cites specific to aviation before replacing it. Coastwise (talk) 07:23, 4 February 2011 (UTC)

Electrification of nose wheel
Added this line: Another possible improvement is the electrification of the airplane's nose wheel. At present, landing gear are not driven by an engine on the nosewheel's axle. Instead, the taxying is done using the main engines. - EOS magazine november 2011

Perhaps add some more info

Another issue not mentioned is why turboprop engines and jet engines are more environmental: this has to do with the altitude it allows the aircraft to fly on (the higher, the less air resistance). Piston engines don't allow high cruising altitudes. However, at lower altitudes, piston engines (propelling the aircraft using propellers) are allot more fuel efficient than turboprop and jet engines (operating at the same height). Especially radial and rotary engines are extremely fuel efficient, line engines are a bit less efficient than these (though more than turboprop and jet engines at low altitude) but easier to built.

91.182.172.157 (talk) 10:54, 30 March 2012 (UTC)

Merger of text from Aviation and climate change
As discussed at on the Aviation and Climate change talk page the text from that article has been merged into the text from this stub article, leaving the text from this article as the introduction. Much more work needs to be done to integrate the two articles and expand it to cover such subjects as noise and air quality. - Ahunt (talk) 13:47, 29 December 2007 (UTC)


 * LINK TO THE "TALK" PAGE FOR THE OLD ARTICLE TITLE: Talk:Aviation_and_climate_change


 * Also, I noted shortly after the title of this article was changed that the number of views had dropped dramatically. They have never recovered, so there may be some unresolved multiple redirects from major WP articles on climate.  This goes back quite some time now, so those links in other articles may no longer exist, but if someone knows how to check this, it may be worthwhile. Coastwise (talk) 18:55, 27 November 2012 (UTC)


 * Looking at Special:WhatLinksHere/Environmental_impact_of_aviation I am not seeing any problems there. There are a lot of links into this page within Wikipedia. - Ahunt (talk) 20:43, 27 November 2012 (UTC)

Bias?
I think for the purposes of making the article more encyclopaedic and neutral (certain groups love to attack the aviation industry), there should be a comparison between the effects of the aviation industry with others, such as automobiles, electricity generation etc. I seem to recall from somewhere that per annum commercial aviation only contributes 2-3% of total human carbon emmissions, but there is no suggestion of this in the article.

Another quick point related to this is the article's main picture of an aircraft producing contrails. I think the caption should make it clearer that the trails are composed of water or else find a less damning picture. — Preceding unsigned comment added by 82.239.20.172 (talk)

I don't think this article is aiming for neutral. Quoting research from writers, including their "It's amazing how stupid these people are!" (Paraphrased, of course, but people with an axe to grind often use "cognitive bias" to talk down to those who don't change their minds when presented with a one-sided argument.) 130.76.96.145 (talk) 22:05, 28 January 2013 (UTC)

Could there be more bias in this article?
This article mentions all of the "bad" that aviation does, yet it completely fails to mention the vast numbers of next generation aircraft that are on order (787, 737, A320, A350, A380, and C-Series) to replace the current fleet of aircraft. It doesn't take "decades" to phase out these aircraft as the article suggests, it takes a technology shift which just occurred. Apparently the environmental movement so hell bent on pointing out all the bad of aviation just missed the tectonic shift that took place this year with regard to aircraft engines without even being forced into doing it.

What's it like to be asleep behind the wheel? — Preceding unsigned comment added by 71.154.210.199 (talk)


 * This sort of information can be added, but as per WP:V it needs to be able to cite reliable sources. So if you can point to such sources then it can be added. - Ahunt (talk) 13:28, 27 October 2011 (UTC)


 * Well, here's one that shows that not a single US carrier has average aircraft ages in the decades (20+ for pluralization). http://airsafe.com/events/airlines/fleetage.htm  This site agrees with average age being under 20 (though it mentions some a/c from the 60s), and states that the US has some of the oldest planes running.  http://articles.cnn.com/2010-02-01/travel/planes.age.dreamliner_1_plane-oldest-fleets-passengers?_s=PM:TRAVEL  Talks about retiring gas guzzlers for fuel economy, pointing out it has one of the older fleets in America.  http://blogs.wsj.com/middleseat/2011/07/20/trading-in-gas-guzzler-planes-at-american/  Gas guzzler aircraft losing value.  http://www.flightglobal.com/news/articles/older-aircraft-values-heading-south-223602/  Fuel-sipping 787 best selling new twin aisle ever.  http://earth911.com/news/2011/09/28/boeing-787-dreamliner-fuel-efficient-airplane/  Google A-350, 787, 737 MAX, or A-320 NEO.  Not only will it bring up dozens of articles on them, they almost always say "fuel efficient" or something similar as the adjective in the title.  Heck, look em up on Wikipedia.  You'll see record sales for them.  Nevermind the articles on the Next Gen aircraft control systems, which are designed to reduce emissions...  If you can't find reliable sources, you haven't looked.  And that is precisely the point the people talking about bias are saying...  Nobody who has contributed to this flame piece have looked at the other side. 130.76.96.145 (talk) 22:24, 28 January 2013 (UTC)

New aircraft designs
Perhaps new aircraft designs such as blended wing body aircraft and other airplanes with other improvements can be mentioned in the article (new article section). Notable are:
 * the MIT silent aircraft
 * the SUGAR Volt (a hybrid aircraft)
 * the MIT Double bubble D8 MIT Double bubble D8

109.130.138.81 (talk) 11:12, 16 January 2013 (UTC)


 * In my view these concepts are speculative and not appropriate for the article. Similar concepts have existed for decades, but there has been no move toward even a prototype. I think the article should be about the environmental impact of aviation in its present state, including technology that has been demonstrated and could be widely implemented within several years. Even something like the Boeing Dreamliner won't have a measurable effect on the impact of the industry for decades, since most existing airliners will still be airworthy for quite some time. Coastwise (talk) 18:09, 16 January 2013 (UTC)


 * Decades? With mild increments in the 2-3% range in fuel efficiency, most airlines have been retiring their gas guzzlers before they hit 20. With 20% fuel efficiency improvements, airlines will be retiring them younger and younger.  It isn't about airworthiness for commercial aircraft, it's about financial decisions, and with the operating costs on fuel alone...  The 787, A-350, and upcoming A-320 NEO and 737 MAX are going to upend the apple cart. 130.76.96.145 (talk) 22:31, 28 January 2013 (UTC)

Extra things to implement to article
Some things that need to be implemented in the article are: KVDP (talk) 12:56, 19 February 2013 (UTC)
 * Continuous descent approach (I placed this at the see also section, yet should be explained in text)
 * Assisted take-off: Airbus presented this option in his Smarter Skies proposal. Should reduce fuel consumption considerably, especially for jet-engine powered aircraft (these operate only efficiently at high altitude)
 * Use of aircraft with Contra-rotating_propellers: aircraft with propellers (contra-rotating ones as the regular ones allow too slow a speed to be attained, in order for the airline companies to use their plane economically) seems to be on the rise. The airplanes discussed in the section above (MIT silent aircraft, SUGAR Volt, MIT Double bubble D8 ) btw use propellers too, so it shows this is going to be where the industry is working towards. Propeller aircraft are much more fuel-efficient than jet-aircraft (well, atleast at a lower altitude, and at a slightly lower speed).

Increased impact of night flights
The contrails themselves create a significant short term cooling effect during the day/morning and warming effect during the night/evening. This was observable on Sept 12, 2001 when were few commercial flights. World average temperatures were 0.5C higher that day. Not only is this alarming that the world average temperature is actually 0.5C higher than we think, but it also means that by encouraging flights during the morning rather than evening would help reduce world temperatures.Cam Forman (talk) 12:14, 22 June 2013 (UTC)


 * As per WP:V we need references to add this to the article. - Ahunt (talk) 21:57, 22 June 2013 (UTC)

Environmental impact statements
Mention what environmental impact statements are required in regards to the. Jidanni (talk) 03:14, 20 November 2013 (UTC)


 * Not sure what you are suggesting here. Can you explain? - Ahunt (talk) 13:08, 20 November 2013 (UTC)

Environmental impact on aviation
Do we need a new article for this or could this be incorporated into this? i.e. Climate change to increase flight turbulence http://rt.com/news/climate-change-air-travel-science-transatlantic-541/ prokaryotes (talk) 09:24, 29 December 2014 (UTC)
 * That could go in this article. I will add it. - Ahunt (talk) 13:09, 29 December 2014 (UTC)
 * ✅ - Ahunt (talk) 13:20, 29 December 2014 (UTC)

Monbiot article
Hi, are there any alternatives to the Monbiot quotations? The article is not very good from a technical perspective. For example, It is my opinion that the article is very heavy-handed, and has cherry picked to support a point. There are kernels of truth in the article, but it synthesises very heavily, and rarely considers all the alternatives. If there are any substitutes, such as from some kind of academic or government literature, this would be far better 129.67.86.87 (talk) 20:48, 24 August 2015 (UTC)
 * He offhand quotes a figure for hydrogen energy density, but does not consider that liquid hydrogen, or high-pressure hydrogen, will have different (and much higher!) densities.
 * He states that as planes are bigger they have more drag and thus they must fly faster, which is not true at all (think a C-130, vs say, a blackbird), and is completely nonphysical (drag must balance thrust, and lift must balance gravitational force) - I assume he is vaguely thinking of scramjets, but is somewhat confused. As an extreme counter-example, rockets have been used on planes for added lift (there is a good video somewhere on wiki showing rocket-assisted short-runway takeoff).
 * He assumes that there is no way to close the demand equations to account for additional demand due to dditional capacity (it could well be (and probably is!) convergent)
 * He assumes the only way to decrease fuel consumption is to ground planes. This is not true, they could fly much slower, and reduce consumption that way (eg Solar Impulse)

Update needed on Int'l GHG regulation
There are two outdated sections, Kyoto Protocol and Emissions Trading. These should be revised and put under an overarching section, International Regulation of Aviation GHGs. The existing material (with some revision) can be historical subsections. The more recent news that needs to be included is the failure to initiate the European ETS scheme a few years ago due to pressure from China and others, and the fact that aviation emissions were once again not included in the most recent COP, in Paris. One article that may contribute to this is: "Omission of aircraft pollution in Paris deal worrisome: EU climate boss" at, and surely there is other coverage. I am short on time for taking this on, so am hopeful that someone else will -- not a very big task. Coastwise (talk) 17:46, 3 January 2016 (UTC)

What about the "clean-up / reorganize" tag?
A clean-up/reorganize tag was placed at the top of the article in December 2014. No specific problems have been pointed out here on the talk page, nor has any discussion taken place. In the absence of that, can the tag be removed? What is the policy on that? Coastwise (talk) 22:44, 17 February 2016 (UTC)
 * If there was no explanation or clarification given and it no longer seems justified then it can just be removed. - Ahunt (talk) 17:44, 18 February 2016 (UTC)

Fuel use per passenger?
This article would be greatly improved with a breakdown of kg/l of fuel per passenger km/mile for various types of aircraft and routes. It is good that there is much on CO2 emmissions per passenger for distance travelled but it could benefit from a more basic comparison of amount of fuel used in addition as opposed to only concentrating on one resulting emmission from the burning of fuel resources.

For example:

149.241.194.134 (talk) 17:29, 23 January 2014 (UTC)


 * We would need sources to add that. Do you have any? - Ahunt (talk) 19:36, 23 January 2014 (UTC)


 * I think it is a bit complicated, since cabin arrangements (e.g. amount of 1st class & business class as well as seat spacing generally), load factor and number of stops enroute to a destination are significant factors. Also, the operations protocols of various airlines. So it is an airline thing as well as an aircraft thing. One stab at this has been made by CarePlane.org (now either down for service or inoperative, see ), which has a beta CO2 calculator. This was based on an extensive proprietary database of actual airline practice (kinds of factors above as well as aircraft type), and also took into account the delays at specific airports at various times of year. If the service is still available, it is interesting. However, try several of the recommended web browsers as one or another gives spurious results at different times (apparently a problem with keeping up with changes to browsers or their use of Javascript). The range of emissions performance was quite broad, even for different times of day for the same equipment and route on the same airline. Of course all results were an estimate based on average estimated performance within some block of days or weeks. Coastwise (talk) 05:15, 24 January 2014 (UTC)


 * I agree it would be far more useful taking into account all of the various factors and including breakdown by class travelled etc. I am curious because to arrive at a figure for CO2 emitted in the article surely the ammount of fuel used to create the emissions has been taken into account prior to factoring and adjusting for engineering and design efficiencies, weather, routes etc. So the data must be around somewhere and it would be useful to include more thorough workings of equations used to arrive at definitive data sets. 149.241.203.47 (talk) 13:27, 24 January 2014 (UTC)


 * For italian national trains (run by the FS Trenitalia company) the comparison of private car / airliner / train travel is printed on the backside of the cardboard ticket, in terms of kilograms of CO2 greenhouse gas emitted per capita. For example: Milan to Naples, 775km / 481 mi journey, it pollutes 31kg to go by train, 76kg by car and 115kg by airplane. (It should be noted that Italy obtains a large part of her electricity needs by importing it from french nuclear power stations, so the electrified italian railway mainlines can be very CO2 lean compared to fossil fuelled cars and airplanes.)
 * Furthermore, italian railway mainlines like Milan-Naples are served at 250 to 320km/h high-speed, city center to city center, so the door-to-door travel time is equal or less compared to airplanes, which need to take off from e.g. Malpensa or Bergamo runways, both of which are ~70km apart from Milan city center. So the situation with intra-national "modal split" of train and plane travel is not hopeless in most european countries.
 * The big problem is trans-national train travel losing ground to low-cost air carriers, even in unified Europe. That's because all railways want freight and freight for maximized profit and only serve those profit-neutral or even lossy pax trains which the national government forces down their throats via laws and ordinances. The EU currently doesn't force national railway companies to accept trans-national pax carrying trains unconditionally. This creates a bonanza for highly polluting short-hop, low-cost flights, which all EU nations are forced to accept under "European Free Skies" treaty.
 * (E.g. the Budapest-Venezia direct train has been running for 120 years, last 50 of that throughoutly electrified and then in 2011 Trenitalia suddenly sold its Venice head station track-time slot to a french private railway, game over. Overnight, Ryanair and WizzAir jumped in to fly Budapest-Hungary to Treviso a.k.a. Venice low-cost airport. Except that a single train of 7 carriages carried 560 pax on nuclear volt-amps, straight to the canal bank, while a single low cost A320 or B-737 plane carries just 188 pax on fossil fuel, to the middle of nowhere, i.e. rural countryside .91.82.39.56 (talk) 21:30, 20 August 2016 (UTC)

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Operations_efficiency
One option that I have not seen mentioned is in regards to the aircraft engine preheating phase (the aircraft engine is normally run on the ground well in advance of take-off to preheat the engine). See also here. The thought I'm having is that this fuel could be fed to the aircraft via a fuel line connected to the aircraft. That way, storage space in the the fuel tanks isn't wasted (some of the fuel in the tanks will otherwise be spend even before take-off). In practice, it means that the aircraft is made to carry an extra tank (which increases the aircraft's weight causing a slightly higher fuel consumption).

If the aircraft would instead be connected to a tank on the ground, using a fuel line, this extra tank in the aircraft wouldn't be needed (otherwise put, if you were to fill up all tanks in the aircraft, all fuel would actually be spend on propulsion, and so the aircraft would be able to fly a bit further -which could be important for long-haul flights-).

Besides this -and here comes the intresting bit-, the fuel fed via the fuel line to the aircraft warming up its engine on the ground, could be hydrogen. Hydrogen could be generated on-site, and as such does not need to be stored. Since it doesn't need to be stored, there's no need for a tank that is able to withstand very high pressure (important !, as aircraft tanks are not able to withstand the pressure needed). Also, hydrogen is both emissionless, and it will also be far cheaper than aviation fuel (like kerosene).

Perhaps that we could mention this in the article, if there are any notable reports that detail this idea.

KVDP (talk) 10:37, 19 March 2017 (UTC)


 * The Aopa preheating article refers to piston engines apparently. Airliners engines are started after the pushback, when the aircraft is disconnected and moving. Turbofan startup times are quick, the Pratt & Whitney PW1000G was bashed for being over 150 seconds at introduction. The taxi fuel isn't even that important (e.g. for an A320, 400kg max for 22t fuel capacity, %) EGTS was an electric taxiing system to save fuel, but now fuel is cheap again its cost couldn't be justified.--Marc Lacoste (talk) 13:35, 19 March 2017 (UTC)


 * I agree, turbine engines require very little warm-up time, unlike piston engines. I have had PT-6s from start-up to airborne in under a minute with everything "in the green" at lift off. It just isn't a factor, so you are unlikely to find refs about this. - Ahunt (talk) 13:39, 19 March 2017 (UTC)

EMALS: new aircraft designs
Just read the article on EMALS, see http://www.treehugger.com/aviation/civilian-airplanes-could-one-day-take-off-electric-catapults.html and http://www.economist.com/news/technology-quarterly/21598325-electromagnetic-launchers-hurling-objects-electrical-energy-giving

I'm wondering whether we shouldn't mention that the catapults could allow the plane designers to make aircraft designs with far smaller/less powerful engines (hence also burning less fuel). The idea I have is that the engines currently need to be quite powerful to allow the plane to get airborne, but if the plane is helped into the air with the catapult, that won't be needed any more, and the engines only need to be powerful enough to help it "stay in the air" (and propel it at say 800 km/h) instead.

Also, I haven't made up from the articles on whether they intent to use a new plane design (with strengthened airframe) or just strengthen existing plane designs, or whether they'll use an extra frame/trolley or something instead (this is important because in the case a new plane design is needed anyhow, integrating less powerful engines would certainly be an option). KVDP (talk) 17:38, 9 June 2016 (UTC)


 * All that really doesn't matter. When flying at 11km altitude, an A-320 or B-737 (typical low cost airline's plane that carries max. 180-189 passengers) generates app. 60000 horsepower equivalent with its jet engines, to maintain a typical cruise speed of 850 km/h versus the drag. In contrast, a TGV-like bullet train that carries 500 people, generates about 15000hp in its electric motors at 320km/h sustained top speed. That is, in the bullet train 3x more people are carried with just 1/4th of the energy consumption at roughly 1/3rd of the speed.
 * But one must also consider that up to 750 / 1000km distance, a 300 / 350 kmph top speed bullet train has better or equal door-to-door travel time compared to planes, since it runs from city center to city center, while most airfields are located far from urbanism, due to noise problems. Railways are also free from the time consuming post-9/11 personal screening hassles. Thus, in a properly taxed and regulated world, airplanes would still be much disadvantaged environmentally and economy-wise for personal travel, even if they used EMALS to get airborne. 91.82.39.56 (talk) 21:49, 20 August 2016 (UTC)


 * So you're saying its better to take the train than the airplane ?
 * I don't think it's up to use to decide what mode of transport they should take. The only thing we can try to do is make the transport options available more environmental.
 * KVDP (talk) 10:19, 19 March 2017 (UTC)


 * No, you're way off. A single aisle needs 60000hp only at takeoff but 15000 in cruise, but propulsive efficiency vary, and a TGV isn't at max hp every time either, so hp isn't a good comparison point. Plus you have to factor in the efficiency of the powerplant and the electric network to power the train. And a TGV isn't the best case everywhere : the infrastructure is heavy and isn't needed for low traffic : when you have 10M pax/year, a HSR line could be justified, but small planes could be more adapted to thinner routes. Total cost including the infrastructure amortisation is the real deal breaker, not the energy consumption.
 * EMALS won't help much, it isn't the takeoff which consumes energy, but the climb - but the potential energy is going back in the descent. The subject of the (original source, treehugger is just a sensationalist blog, not a serious tech reference) economist article isn't airliners but jet fighter carriers.
 * Above this, Wikipedia talk pages aren't a forum to discuss that (go to airliners.net or similar) and certainly not a soapbox to voice your tax and regulations opinions.--Marc Lacoste (talk) 14:03, 19 March 2017 (UTC)

Alternative ways to travel added under "Reducing air travel"?
Would it not be relevant to add a paragraph about alternatives to airtravel under the section about Reducing air travel? I am thinking of mainly trains, but also ferries, even buses could be included. Discussing how these could become more attractive alternatives in comparison to airplanes. This could include all from promoting nighttrains where one can sleep, faster train connections between major cities, subsidies, easier ways to connect travels where one need to change train/ferry/bus, ways to make it more affordable. When I took the train to Paris from Gothenburg(Sweden) I had to walk around several hours in the cold in the middle of the night in cities while waiting for a connection, and it cost more than twice what it cost to fly. It is not so strange people decide to fly then. Another possibility for making people choose slower means of transportation could be to reduce workweeks per year, so that people don't feel stressed to get to their destination, but have time to let the travel itself take some time. — Preceding unsigned comment added by 78.70.95.57 (talk) 03:18, 13 August 2017 (UTC)

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On the positive side
Notwithstanding negative impact of aviation on the environment, as a concept it has to be given credit for the general efficiency in use of its seating capacity (80% by Lufthansa in 2017) as opposed to trains and cars (around 30%-45%). When in cruise flight no significant noise reaches the earth surface and only 3 KM runway (and further airport infrastructure) at departure and arrival point is required for any mileage flown in between. — Preceding unsigned comment added by Guppiebugs (talk • contribs) 17:00, 1 July 2018 (UTC)

Press article offers new, unsettling commercial aviation CO2 emissions data "from the horse's mouth".
https://www.theguardian.com/business/2019/oct/10/british-airways-offset-domestic-flight-emissions-from-next-year

British Airways to "offset" domestic flight emissions from next year, carbon neutrality pushed back to 2050. Article by Gwyn Topham, transport correspondent, The Guardian, 2019 October 10

The gist: British Airways states their domestic air travel impact is 400 kilotons of CO2 gas emissions per annum. The entire IAG (BA parent company) global impact is 29.9 megatons of CO2 exhaust / year. Entire global aviation industry is 915 million tons (!) of CO2 emissions / year. A single London-Toronto flight consumes 70 tons of jet fuel in a B-747 Jumbo Jet, which continues to serve until 2024, versus 43 tons in a new A350-1000 twinjet plane.

BA boss states they consider 3.2m euros (3m UKP), i.e. 1/40th the price of a single new Airbus 321 jet airliner, as full voluntary off-set compensation for their 400kT british domestic CO2 emissions. They refuse to compensate globally, because kerosene-fuelled long distance aviation has no alternative and people are societally entitled to fly and other airlines of the world should also act. Greenpeace UK's spokesperson has expressed distress about those statements. 80.99.111.252 (talk) 10:18, 11 October 2019 (UTC)


 * WP:NOTFORUM--Marc Lacoste (talk) 10:41, 11 October 2019 (UTC)


 * The new data from IAG British Airways, as quoted in the press repor, should be incorporated in the Wikipedia article, that's why I entered it here. 80.99.111.252 (talk) 11:41, 18 October 2019 (UTC)


 * Be WP:BOLD, do it. Others will correct mistakes if any.--Marc Lacoste (talk) 18:49, 18 October 2019 (UTC)

Non-CO2 radiative forcing effect, reference quality
Hey friends,

I've been researching this topic a bit. In a few places here the article refers to the actual radiative forcing effect of aviation to be several times worse than from just the CO2 emitted (presumably from carbon particulate, NOx generation, and water vapor). However, i can't find a source for these numbers and am worried it is inconsistent with the current scientific consensus.

Reference 38 in the article says the IPCC says it's several times higher: A round-trip flight between New York and Los Angeles on a typical commercial jet yields an estimated 715 kilos of CO2 per economy class passenger, according to the International Civil Aviation Organization. But due to the height at which planes fly, combined with the mixture of gases and particles they emit, conventional air travel has an impact on the global climate that’s approximately 2.7 times worse than its carbon emissions alone, says the Intergovernmental Panel on Climate Change. As a result, that roundtrip flight’s “climatic forcing” is really 1,917 kilos, or almost two tons, of emissions ..but there is no citation.

Here's what i found in IPCC WG3 AR5, p.611: Relative to CO2, major short-term impacts stem from black carbon, indirect effects of aerosols and ozone from land vehicles, and aerosols and methane emissions associated with ships and aircraft. Their relative impacts due to the longer atmospheric lifetime of CO2 will be greatly reduced when integrated from the present time to 2100 ipcc 2018

It's possible the author of ref 38 is referring to this 1999 IPCC study and the associated radiative forcing bar charts. ipcc 1999

But more recent publications are more circumspect about the impacts of non-CO2 aviation emissions. Here we do not include the effects of aviation emissions on contrails and cirrus clouds. The IPCC estimates a RF of 10 mWm−2 for the contrail effects (2), although the impacts of aviation emissions on cloudiness are highly uncertain nasa 2010

This paper on contrail radiative forcing says this: The global net radiative forcing of contrail cirrus is roughly nine times that of young contrails, making it the single largest radiative forcing component connected with aviation. It is important to note that contrail cirrus have a much shorter lifetime than long-live greenhouse gases. This difference in lifetime influences the relative importance of contrail cirrus and other forcing agents for climate change when estimating their impact for remote time horizons. Nature 2011

Thoughts? Any experts lurking on here? < Wes Hermann (talk) 03:01, 2 December 2019 (UTC)


 * I'm less experienced than you on this subject, but good references are always good to add, and they could balance a current bias.--Marc Lacoste (talk) 21:00, 2 December 2019 (UTC)

Merger proposal

 * Support as very closely related Chidgk1 (talk) 17:08, 5 January 2020 (UTC)


 * Oppose if you are talking about merging Mitigation of aviation's environmental impact into this article then that is not a good idea. Both are already long articles and the resulting article would be very long. See Article size for guidance. This article is already 98 kb and the other is 17 kb. As noted, articles of 100 kb should be considered for splitting into shorter articles, not combining into longer ones. What would be gained from combining them? - Ahunt (talk) 20:03, 5 January 2020 (UTC)


 * Support I proposed the merge to to multiple redundancies between them. A merge would avoid maintenance problems. If the resulting article is too long, the largest subsection may be split appropriately, not obviously this Mitigation part.--Marc Lacoste (talk) 21:36, 5 January 2020 (UTC)


 * Support It would likely increase page views, and it makes more sense. Also both these articles I think should be seriously condensed. MurrayScience (talk) 19:53, 8 August 2020 (UTC)


 *  Support In line with popular views to condense both articles while reducing the multiple redundancies between them, I pledge to undertake the task Omolisa (talk) 19:10, 28 August 2020 (UTC)


 * I agree we should go ahead. We can split the workload, but I'm not available before next tuesday.--Marc Lacoste (talk) 18:43, 1 September 2020 (UTC)

Bias issues
I have read through this entire page and there appears to be an anti aviation bias in some areas. Given wikipedia is meant to be a neutral information provider this should be looked into and corrected. — Preceding unsigned comment added by 150.143.83.232 (talk) 17:44, 18 October 2020 (UTC)


 * If you can cite reliable sources it would be great if you could correct it. If you have any technical problems editing please ask. Chidgk1 (talk) 09:25, 19 October 2020 (UTC)


 * I'll agree the article in its current state is a difficult to digest aggregate of main facts and low-importance factoids, with references sometimes difficult to verify, and upper limits of the statistical range presented without the lower limit. It would be a great thing to do to go through it and revamp it.--Marc Lacoste (talk) 07:39, 20 October 2020 (UTC)
 * The article is in quite a state indeed. I don't think there is anti-aviation bias on average (anymore?). The article contains biases both ways, with sentences like : Airport neighbours' sleep is facilitated by night flying restrictions including night flight bans. Not all airports do this, so should be framed neutrally. Femke Nijsse (talk) 12:39, 27 November 2020 (UTC)


 * You can try to rephrase it neutrally. By now, I went through most of the article, leaving the "CORSIA" and "Alternative fuels" parts to revamp. The final part will be to revamp the lead section.--Marc Lacoste (talk) 13:36, 27 November 2020 (UTC)

I'm always so happy when I see people have the guts to bin large chunks of overly specific text. Thanks for your efforts. I reworded and found a source for the statement. Femke Nijsse (talk) 16:48, 27 November 2020 (UTC)

Airlines arguing they are carbon neutral
Given the fact that carbon offsetting schemes are almost never as effective as they hope to be, we cannot state in wikivoice that these airlines are carbon neutral, at least not with these sources. In 2008, these discussions were not yet developed. The websites of these airlines themselves are inappropriate here, and probably too specific for this article. Femke Nijsse (talk) 14:09, 2 December 2020 (UTC)
 * It's a claim then.--Marc Lacoste (talk) 18:01, 2 December 2020 (UTC)

Alarmist POV and references verifiability
Hello,

An alarmist WP:POV maybe given WP:Undue weight, borderline obfuscation, with references from scientific papers giving them an argument from authority with lengthy and intimidating WP:DOI identifiers, but difficult to verify: convoluted academic writing using jargon, sometimes behind WP:PAYWALLs, sometimes cherrypicked by extracting the information an aviation-critic wants but not giving the other side.

Please try to be flawless with your reference mining. Thanks.--Marc Lacoste (talk) 09:46, 12 May 2021 (UTC)

Assumptions and other issues
This article makes the critical assumption that the environmental impact is wholly composed of in-flight emissions. While in-flight emissions do account for the lion's share of aviation emissions this should be explicitly stated. Other contributers such as infrastructure and manufacturing of airplanes should still be addressed. Mining of metals and particularly rare earth minerals used for electronics and electricity requirements of airports are particularly obvious environmental impacts. It would be interesting to see also what the environmental impact of end-of-life aircraft is.

In terms of operating emissions, what proportion arise from take-off, landing, cruising and taxiing? Philipp.governale (talk) 03:59, 24 May 2021 (UTC)

Two removed sections
I have moved these two sections from the article to here for further work as they are not ready for mainspace. I had tried to edit them to fix the awful grammar and sentence structure, but in fact I think, even with that all repaired, most of these additions add up to very little substance and some duplication, and I am not convinced there is much here that can or should be saved.

If any editor would like to propose new versions of these please add your version below, or alternatively, discuss: {{talk quote block|

Stages of Flight
There are many stages in a flight that have different amounts of carbon emissions such as take offs, landings, and taxiing around to different terminals and gates at the airports. Some misconceptions of emissions from aviation is that a majority of the emissions come from take off and landing, but a study in 2010 showed that taxiing and idling is the largest source of emissions in the landing-takeoff cycle. About twenty-five percent of emissions come from this landing-take off cycle, which means that connecting flights are actually worse for the environment than direct flights that might be longer because with connecting flights there are more frequent landings, taxiing, idling, and takeoffs that are unnecessary.

Often times there is a queue of aircrafts that are waiting to take off, while stopped in this queue on the taxiway, about 18% of the aircraft's fuel is being consumed. Data taken in 2012 showed that 18m metric tons of C02 is released just in the taxiing portion of flight takeoffs. Aircrafts taxiing accumulate for about 76% of fuel consumption in the take off process while accelerating only takes about 3%, other factors include making turns on the taxiway which requires about 6% of fuel consumption, and the rest of the 15% of fuel consumption is used when the aircraft is idling on the taxiway.

While short term solutions would include more efficient trafficking on runways, as well as enhanced tools for ground and local controllers to control traffic, the long term solution has to come from the aircraft manufactures themselves. }} and {{talk quote block|

Integrating Modeling
With the improvement of scientific knowledge and integrated modeling the FAA can better understand the environmental effects of aviations and can set regulations and goals for the organization to meet to become more environmentally aware. The FAA will only make decisions after seeing that they are backed up by scientists, so creating models that can take into account the cost-benefits analysis of potential solutions it will help the FAA's advanced decision making process

Center of Excellence (COE) is a partnership that the FAA has been working with almost two decades. The COE complies of 75 universities around the United States that has helped the FAA by advancing aviation science and technology to help bring solutions to the problems that are being created in this industry, while also helping the FAA have a return on their investments.

Airport Cooperative Research Program (ACRP) is another research program which is managed by the Transportation Research Board (TRB) of the National Academy of Science. Although they are managed by the National Academy of Science they are funded by the FAA to help research and create new practical solutions to airport operations. A number of the research that the ACRP has done has included the environmental concerns of aviation as well as proposed some practical guidance for airports to incorporate to reduce their emissions. Since this program is authorized in the FAA it is anticipated that this program will continue to perform research projects and grow in the future leading airports in more guidance on how to improve their environmental performance. }}

- Ahunt (talk) 03:15, 27 November 2021 (UTC)


 * Hello Adam, thanks for your scrutiny! Indeed those sections aren't top notch. The 1st one, Stages of Flight, could be interesting as it focuses and savings that can be done on the ground ops, but it's not very precise technically, and does not demonstrate a good understanding of the underlying parameters. It could be enhanced, though. The 2d one, Integrating Modeling does not really makes sense. OK, the FAA has a program of some sorts. But there are no dates, no data, no goals, no results: no real info. Useless as it is now.--Marc Lacoste (talk) 07:40, 27 November 2021 (UTC)
 * That was pretty much my take on these as well - plus the grammar is so bad it makes them hard to figure out what was trying to be expressed anyway. Perhaps the first para could be re-written and the second just omitted. - Ahunt (talk) 13:23, 27 November 2021 (UTC)


 * The two editors involved, user:Tjpratt24 and user:Haleyferraris, are both Wiki Education student editors from Wiki_Ed/Bentley_University/NASE_337-1_Global_Climate_Change_(Fall_2021). Not the standard of quality I expected.--Marc Lacoste (talk) 08:56, 28 November 2021 (UTC)


 * Oh, I had figured these must be editors working in a second language and was going to suggest that they might be more comfortable working on the version of Wikipedia that is in their first language. Bentley University is a private university focused on business and located in Waltham, Massachusetts ... - Ahunt (talk) 15:01, 28 November 2021 (UTC)


 * Sorry it seems I'm the only non-native english speaker right now :D --Marc Lacoste (talk) 19:55, 28 November 2021 (UTC)


 * - Ahunt (talk) 20:15, 28 November 2021 (UTC)

Wiki Education Foundation-supported course assignment
This article was the subject of a Wiki Education Foundation-supported course assignment, between 8 September 2021 and 17 December 2021. Further details are available on the course page. Student editor(s): Haleyferraris, Tjpratt24. Peer reviewers: Fcatauro.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 20:41, 16 January 2022 (UTC)