Emission control devices on aircraft?

[A2G]

Have some time to kill, thought I'd start a discussion on here cus I was thinking about this. Since aircraft are some of the worse vehicle polluters(only after big ships I believe) and most of the pollution is at altitude, it would make sense to start installing emission control devices.

I imagine the main reasons they have been left out so far, is the added cost and weight(and maybe slight performance decrease). But an EGR system and catalytic converters can't add that much weight! This is obviously for piston engines only. Not sure what can be done to turbines tho.

So I figure this could be a good discussion for here?

[E-Flyer]

Only if airbus was german and would use the blue tech technology on planes like they used on cars and we wouldn't be talking about emissions.

Honestly though, doesn't a Honda Civic with 1 person in it have a larger emission / person ratio than a fully loaded 747 ?

[iflyforpie]

Actually, the large turbine engines have drastically reduced harmful emissions over the years through better fuel nozzle and combustion chamber designs; including unburned particulates (smoke), NOX, and CO.

It comes down to several factors why you don't see it on small aircraft.

First, they are a very tiny fraction of the polluting vehicles out there. Given that the most popular light aircraft has yet to break 50,000 sales and most fly a fraction of the hours that cars are in operation, they can be given some leeway.

Leaded fuel is still required to run many aircraft engines, which would destroy catalytic converters.

Catalytic converters are heavy, expensive, hot, and would be difficult to mount on an aircraft.

A PCV would be another thing to potentially clog and cause an engine failure.

An EGR requires additional plumbing and a control system to ensure the engine isn't being 'choked out' by excessive exhaust gasses, but not burning hot enough to produce NOX. The basic carburetor and hydro-mechanical fuel injection systems don't lend themselves to this.


For most of the places I fly to, I wind up burning less fuel than I would if I drove.

[iflyforpie]

On a side note about diesel powered vehicles....

The fact that I can create IFR conditions behind pretty much any modern diesel truck by pressing down the gas pedal leads me to believe diesel emissions requirements aren't as strict (again, not as many produced). The great mileage you get is because diesel has a higher energy density than gas--not because the diesel engine itself is any more efficient.

[baby_fly]

On a side note about diesel powered vehicles....

The fact that I can create IFR conditions behind pretty much any modern diesel truck by pressing down the gas pedal leads me to believe diesel emissions requirements aren't as strict (again, not as many produced). The great mileage you get is because diesel has a higher energy density than gas--not because the diesel engine itself is any more efficient.

You are partly correct, IFFP. It is true that diesel does have a higher energy density than gasoline, and this does contribute to the higher mileage you get in diesel cars. But, the diesel engine itself is the most efficient of all internal combustion engines.

http://en.wikipedia.org/wiki/Diesel_engine

[A2G]

On any modern diesel vehicle, black smoke indicates a problem, usually an airflow issue due to a broken turbo wastegate. Black smoke means unburned fuel, and on new direct injection diesels, and even newer indirect injection(my truck engine) you should never see black smoke. Unburned fuel also raises EGT's which can destroy a turbo, or even melt a piston! Don't ask me how I know

I don't know the math on per person emission ratio for aircraft, but I have heard many people(scientists too) say it is high. The other important fact is that these emissions are released at high altitude, therefore the Earth's natural filtering(organic elements, like plants and trees) is drastically reduced.

[goldeneagle]

I don't know the math on per person emission ratio for aircraft, but I have heard many people(scientists too) say it is high. The other important fact is that these emissions are released at high altitude, therefore the Earth's natural filtering(organic elements, like plants and trees) is drastically reduced.

Oh here we go again, the infamous 'scientists' who never seem to have a name when they get quoted on such things. If it's truely been published by a 'scientist', then it's out there in a peer reviewed journal, and, there is a name attached. They depend on that name attached to the journal as a publishing credit, and, without publishing credits, the career is over.

Why is it then, folks are always quoting 'the scientists', but can _never_ seem to say just _which one_.

If you want to quote 'the scientists', then, go learn how to do the math, find the journals in which they are published, confirm the math, and report back with a name. Oh, btw, it's not going to be easy, because what you will find, _most_ of such rubbish attributed to the 'scientists' is actually second had interpretation by folks who are clueless, and never have read an academic paper in thier life.

[iflyforpie]

Oh, btw, it's not going to be easy, because what you will find, _most_ of such rubbish attributed to the 'scientists' is actually second had interpretation by folks who are clueless, and never have read an academic paper in thier life.

Where is your source for this information?

[Driving Rain]

We put catch cans on our float planes.

[A2G]

The scientist part was just taken from news reports, where people are introduced as scientists. If I cared enough I could probably dig up the article to quote the persons name, but it's not really that important.

But I do agree with you about some bogus scientist claims, mainly the ones a few years back who said there was no global warming/climate change. Turns out they were in fact scientists, but they hadn't written a paper in decades, and were paid by big oil to make those statements.

Anyways, back to the topic. All we need to find out is how much Co2 an aircraft emits. I'm going to do a search later, but I bet that info isn't too hard to find.

[PanEuropean]

Since aircraft are some of the worse vehicle polluters (only after big ships I believe)...

Eh? What substantiation do you have for that statement? I doubt that it is correct.

Fuel costs money. Any unburned hydrocarbons that come out of the back end of an aircraft engine represent 100% wasted money to the company operating that aircraft.

My guess is that the improvement in fuel efficiency (which is directly correlated to a decrease in hydrocarbon pollution) in the aircraft engine industry over the past 30 years has been far, far better than the improvement in fuel efficiency in automobiles, buses, trains, or any other form of public transport.

The air carriers have tremendous incentive to buy only the most fuel efficient aircraft possible, simply because fuel is the single biggest non-capital expense that they have. The marketplace has demonstrated the truth of this - look at how many perfectly serviceable (but fuel-inefficient) aircraft have been withdrawn from service and parked in the desert over the past 15 years.

Michael

[fortis risk]

Ship is the most efficient way to transport. Here is the breakdown of different modes of passenger transport and their energy load. It does not consider small airplanes but a person, if so inclined, can simply do the math and quickly see that small airplanes are very inefficient in general.

Aircraft like the Q400 bring the energy load close to train level. Aircraft like 727s used in cargo operations....

But if we really want to find a culprit its the Bizjet, anyone who has worked on this side of things knows how ridiculous it is for one or two people to board an aircraft that is better suited as a regional jet.

This is measured in BTU's

Air, certificated carrier
Domestic operations 3,098
International operations 3,691
Highway
Passenger car 3525
Other 2-axle 4-tire vehicle 4016
Motorcycle 1754
Transit motor bus 3262
Amtrak 2100

Source:http://www.bts.gov/publications/nationa ... 04_20.html

[A2G]

Since aircraft are some of the worse vehicle polluters (only after big ships I believe)...

Eh? What substantiation do you have for that statement? I doubt that it is correct.

http://gas2.org/2009/06/03/one-containe ... lion-cars/

and http://peakoil.com/environment/pollutio ... 52590.html

Ships use bunker fuel, the worst types or diesel fuel there is.

[goldeneagle]

Oh, btw, it's not going to be easy, because what you will find, _most_ of such rubbish attributed to the 'scientists' is actually second had interpretation by folks who are clueless, and never have read an academic paper in thier life.

Where is your source for this information?

I actually read enough of the original reports in journals to see how they get twisted and 'spun' for the popular press. You should try it some time, it's a very enlightening experience.

[iflyforpie]

Oh, btw, it's not going to be easy, because what you will find, _most_ of such rubbish attributed to the 'scientists' is actually second had interpretation by folks who are clueless, and never have read an academic paper in thier life.

Where is your source for this information?

I actually read enough of the original reports in journals to see how they get twisted and 'spun' for the popular press. You should try it some time, it's a very enlightening experience.

Of course it gets spun by the press. I stopped watching and reading regular news sources for reliable information long ago...

But reading reports by similarly accredited professionals with complete opposite theses leads me to question the soundness of any of the material. I prefer to study history where 90% of these great-sounding theories have been debunked by the simple passage of time....


The end of oil will be most likely be marked with the same significance as the passing of the 8-track or the square rigged sailing ship. By the time it happens, nobody will care.

[SuperchargedRS]

You want to worry about pollution go to the big companies they are the major players in the smog game, ever hear of a car or plane with a Global Emissions Credit?

China (the mexico of the east) doesnt even have a EPA! nor do most small countries

Also ever see the size of the battery in the back of a prius? that would be the same car that gets the same millage as a corolla? lol

I think people get tunnel vision on this whole emissions thing and dont look at the real and major causes.

It seems like the same guy that will go out and buy a BS hybrid will have a job at a styrofoam factory lol