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FAA Plans to Clean Up the Skies

coondoggie writes "On top of its recently announced plan to reduce flight delays, Federal Aviation Administration officials today launched what they hope will be pan U.S. and European Union joint action plan to cut greenhouse gas emissions from aircraft. Specifically the group announced the Atlantic Interoperability Initiative to Reduce Emissions or AIRE — the first large-scale environmental plan aimed at uniting aviation players from both sides of the Atlantic."

24 of 249 comments (clear)

  1. Re:Bout time we did something about those skies by bobo+mahoney · · Score: 3, Funny

    Forget about the ozone - I want more CO2. I mean the plants really love that stuff and I like my plants to be healtthy.

    --
    Bobo Mahoney
  2. The cult of Global Warming by Spazntwich · · Score: 3, Interesting

    is getting insane. With China the new carbon dioxide emissions leader we need to focus on finding actual new sources of energy. You know, so China will have some economic incentive to stop polluting so much, not that it would hurt for the USA to cut its emissions drastically as well.

    We need to face facts: Assuming the global climate is as fragile as all of the chicken littles claim, the US and Europe ceasing all greenhouse emissions right now would do nothing to save us from our gradual slide into superhurricane seasons and worldwide desert conditions, simply because India and China are still developing and couldn't give two shits about all of our initiatives if any cost them money.

    I'm still waiting on a testable model (no, not a replica of the globe, trolls) before I jump on this "global warming is both horrible and human-mediated" that so many people seem to have blindly latched onto, drawing absurd conclusions after equating correlation with causation and screaming as shrilly as the most terrifying of harpies when someone expresses so much as a single iota of skepticism at their grand new movement.

    My point is this: Cutting our planes' emissions will do nothing but place further financial strains on us, leading to a relative inability to compete with other countries less concerned about the illusory monster of global warming. In addition to this, it will do nothing to make a marked decrease in our own production of carbon dioxide and other gases.

    This is more government micromanagement that will do nothing but further bring us down.

    1. Re:The cult of Global Warming by EaglemanBSA · · Score: 4, Interesting

      I agree that we need vastly more information than we currently have, and further agree that I don't think the government should be micromanaging like this, but what if some companies found it profitable to do so on their own (fuel optimizations, etc.)?

      Surely there is much yet to discover about our planet and the way it works, and I agree that emissions standards must be scrutinized with respect to their economic impacts...I feel that the knee-jerk reaction Al Gore seems to be trying to illicit is not in our best interests economically, but I don't see any harm in people/companies trying to lessen our impact on the world around us...unless it means killing industry as we know it. There must be a balance of some sort.

      --
      Quiz: True or False -- On a scale of 1 to 10, what is your middle name?
    2. Re:The cult of Global Warming by _Sharp'r_ · · Score: 3, Informative

      Happily for us, according to a Canadian climate scientist, based on the sunspot cycles, we're due for global cooling to start in 2020, so I wouldn't sweat it.

      So just maybe, if the "models" are accurate with regards to greenhouse gases, if we try really hard to produce more every year, we can reverse part of the eventual global cooling trend. Somehow I doubt that's likely.

      However, 15 years from now we'll have the FAA talking about their plan to increase greenhouse gas emissions from planes at the behest of the environmentalists and their allies in big oil who want to regulate people into not using so many alternative energy sources that don't produce enough carbon dioxide.

      --
      The party of stupid and the party of evil get together and do something both stupid and evil, then call it bipartisan.
    3. Re:The cult of Global Warming by MarkByers · · Score: 4, Insightful

      > With China the new carbon dioxide emissions leader

      The US is still winning by far if you look at emissions per capita, which is the more relevant figure. You would expect a country with twicce the population to give out about twice the emissions, everything else being equal.

      --
      I'll probably be modded down for this...
    4. Re:The cult of Global Warming by Hal_Porter · · Score: 5, Interesting

      Freeman Dyson on Climate Models
      The first of my heresies says that all the fluff about global warming is grossly exaggerated. Here I am opposing the holy brotherhood of twilight model experts and the crowd of diluted citizens that believe the numbers predicted by their models. Of course they say I have no degree in meteorology and I am therefore not qualified to speak.

      But I have studied their climate models and know what they can do. The models solve the equations of fluid dynamics and do a very good job of describing the fluid motions of the atmosphere and the oceans. They do a very poor job of describing the clouds, the dust, the chemistry and the biology of fields, farms and forests. They do not begin to describe the real world that we live in.

      The real world is muddy and messy and full of things that we do not yet understand. It is much easier for a scientist to sit in an air-conditioned building and run computer models than to put on winter clothes and measure what is really happening outside in the swamps and the clouds. That's why the climate model experts end up believing their own models.

      There's no doubt that parts of the world are getting warmer, but the warming is not global. The warming happens in places and times where it is cold, in the arctic more than the tropics, in the winter more than the summer, at night more than the daytime.

      I'm not saying the warming doesn't cause problems, obviously it does. Obviously we should be trying to understand it. I'm saying that the problems are being grossly exaggerated. They take away money and attention from other problems that are much more urgent and important. Poverty, infectious diseases, public education and public health. Not to mention the preservation of living creatures on land and in the oceans.


      He also worked out a way to reverse global warming quite cheaply.

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
    5. Re:The cult of Global Warming by LarsWestergren · · Score: 4, Insightful

      India and China are still developing and couldn't give two shits about all of our initiatives if any cost them money.

      Of course they will, if continuing emissions will in the long run be more expensive, and lead to a decrease in living standards.

      For instance - much of Asia gets it fresh water from snow melting in the mountain ranges during the summer. Last couple of years, less snow has fallen, and much of it melts during the winter. Then when spring and summer comes, and it is time to plant crops - droughts.

      I'm still waiting on a testable model (no, not a replica of the globe, trolls) before I jump on this "global warming is both horrible and human-mediated"

      Do you reject all science that doesn't have a complete testable model behind it? In science we can never be 100% sure about anything, but there are other ways to tackle a problem. For instance, we can discover that some gases absorb solar radiation better than others (180 yrs ago), postulate that if this warms stuff on a small scale, perhaps it might also affect thing globally, (110 yrs ago) then we can discover that climate is really really complicated, and we can continue to examine interactions and say with increasing confidence over many decades that humans do in fact effect thing globally (too much to link to, sorry).

      that so many people seem to have blindly latched onto, drawing absurd conclusions after equating correlation with causation and screaming as shrilly as the most terrifying of harpies

      Yeah, you are clearly the rational and un-biased one here. ;)

      --

      Being bitter is drinking poison and hoping someone else will die

    6. Re:The cult of Global Warming by LarsWestergren · · Score: 4, Insightful

      Here I am opposing the holy brotherhood of twilight model experts and the crowd of diluted citizens that believe the numbers predicted by their models. Of course they say I have no degree in meteorology and I am therefore not qualified to speak.

      Do I detect the smell of burning martyr? Let me guess, another one who takes scientific scrutiny of his claims as attempts at censorship.

      It is much easier for a scientist to sit in an air-conditioned building and run computer models than to put on winter clothes and measure what is really happening outside in the swamps and the clouds.

      Lie, some countries have kept records of climate ever since the invention of the meteorological instruments in the 17th century, today we have over 7000 stations that measure land temperatures, we also use satellites to measure sea levels, water and troposphere temperatures.

      --

      Being bitter is drinking poison and hoping someone else will die

    7. Re:The cult of Global Warming by spectrokid · · Score: 3, Insightful

      Is global warming going to kill us? No. Is it the end of civilization as we know it? No. But what is the cost of doing nothing? If you americans need to evacuate long island, who is going to pay indemnities? Who will decide which houses get protected by dikes and which ones are given up? Are you going to tell all these sea-side home owners "too bad, shouldn't have been driving that SUV around.."? Because if you do, I can't predict the climate, but I can predict the lawyers are going to be more busy than the engineers... This has NOTHING to do with tree-hugging. This is like choosing whether we pay for fire-insurance. We can choose to pay a little now, or run the risk of paying a hundred thousand times as much 30 years from now.

      --

      10 ?"Hello World" life was simple then

    8. Re:The cult of Global Warming by LarsWestergren · · Score: 3, Interesting

      Happily for us, according to a Canadian climate scientist, based on the sunspot cycles, we're due for global cooling to start in 2020, so I wouldn't sweat it.

      Sadly, this has also been refuted many times.

      --

      Being bitter is drinking poison and hoping someone else will die

    9. Re:The cult of Global Warming by Biotech9 · · Score: 5, Insightful

      Cutting our planes' emissions will do nothing but place further financial strains on us, leading to a relative inability to compete with other countries less concerned about the illusory monster of global warming.

      this is a ridiculous argument that keeps being brought up as a reason to defer or cancel any planned control of pollution.

      It's flawed in two ways. One, it presumes that any prevention of pollution benefits us only globally, if at all. That if we reduce our pollution by damaging our economy we do it to ward of the *possible* spectre of global warming, and that other nations that might ignore our work (thereby gaining an economic advantage) will damage the environment just as much as we would have done. This is ignoring the fact that pollution may end up being global, but it starts local. Countries with the strictest controls on pollution have the cleanest air, the cleanest water, the lowest incidences of environmental disasters. The benefits aren't that you *might* reduce global warming (if it exists or not), but that you *will* increase the quality of your citizens lives.

      Flaw number two, is that we will be damaged economically by reducing CO2 through legislation. For a start, the US has seen a decrease in CO2 per GDP dollar over the last few decades. Americans are making more money, and doing it cleaner. And it can't be blamed solely on the loss of manufacturing jobs from the US either, as Germany is the worlds largest exporter, and has a much lower pollution level per dollar of goods exported than the US or China.

      in the EU, where environmental legislation is toughest, CO2 per GDP is the lowest in the world. The top rankings show that the countries with least CO2 per GDP are also those with highest productivity in the world. Norway and Luxembourg both have higher GDP per hour worked than the US and still manage to have much lower CO2 per GDP unit.

      The fact is, that it is ABSOLUTELY possible to have stricter pollution controls in place, and yet to be competitive with countries that do not comply to the same high standards.

      This is more government micromanagement that will do nothing but further bring us down.

      As a fellow living in one of the most micromanaged, government intrusive counties in the world, and also one of the richest, cleanest and with the highest standard of living in the world, I would like to say that it is clear to me the US could do with some more open government intervention and less supposedly invisible hand market control. If anything has bought the US down in the last decade, it's been corruption and abuse from large corporations not kept in check by government.

    10. Re:The cult of Global Warming by cheezus_es_lard · · Score: 4, Insightful

      What kills me about these arguments is pretty basic. IF there is an impact from our emissions on our planet, which MAY be negative, and which CAN be avoided, or perhaps lightened, by the decrease in output- why not decrease output? The economic argument is hogwash- these same companies (auto/truck manufacturers, jet engine/aircraft manufacturers) spend millions of dollars in R&D on their products; the spur of forced investment into this field will encourage economic growth, as this cutting edge field matures in whichever country pioneers it. In addition to creating an entire new sector, much as the Ethanol push has done in the USA, and while some companies may suffer, much as with the Prius and other hybrid cars, offering an alternative to the standard high emission models will appeal to some consumers and drive the development of this field and the advancement of technologies and the companies bringing them to market. Forced adoption of these technologies will further spur growth and investment. Again, while some incumbent companies may suffer due to their lack of foresight or corporate dexterity, any loss to these companies in jobs will be made up, likely with gains, in the new industry.

      The argument that other nations are advancing and will surpass our output is also pointless. As a market leader, the USA has the ability to establish products worldwide. The adoption of these products here will spur copycat import products, and likely will result in their use in these developing first-world nations. In addition, the USA can use it's trade imbalances and leverage with these countries to spur their adoption of these technologies- where they're not already leading us, that is, as in India with their 100% natural gas taxi and bus fleets.

      A few technological innovations which could help stem or prevent the devastating impacts of global warming are listed below; some are really basic concepts, too.

      -Zero-emissions gasoline engines via gas/emissions recovery and storage (exchanged for empty containers at gas stations)
      -Biodiesel-producing algae capable of processing the CO2, waste heat, and other emissions from coal-fired power plants and growing from it (already under testing in labs)
      -Battery-powered cars (big capacitors, big nanotech batteries, potentially fuel cells, no problems)
      -Zero-emissions factory environments (heat, water vapor, co2, etc recovered and reused/processed/stored)

      All of these technologies can bring American companies into the 21st century and revolutionize the entire world's concepts of how to deal with emissions- and potentially save a large percentage of the human race while doing it, and reaping enormous profits.

      I like to show people this chart: Wikipedia CO2/Temp Chart because most people, when they see exactly how far off of the normal scale we are, understand that doing ANYTHING is better than saying 'we don't know enough to do anything about it yet!' We all bear a shared responsibility for this planet, and we should do what we can to attempt to preserve it for our descendants.

      love and peace.

  3. Re:impact by Spazntwich · · Score: 3, Interesting

    It seems somewhat counterintuitive that airlines would ignore such an obvious way to save fuel if there weren't tradeoffs involved, considering its one of their single greatest expenditures.

    I've got family of my own in the industry, and I've never heard of any easy fixes for fuel consumption, but I do know airlines have implemented fuel-saving procedures such as taxiing with only one engine on. Given the meager fuel savings that provides but their strong advocacy of it, it just doesn't stand to reason that they would ignore other such easy ways to conserve.

    Do you have any data, studies, reports, anything to back up your claims besides some appeals to authority?

  4. In Other FAA News by Bob9113 · · Score: 5, Funny

    Federal Aviation Administration officials today launched what they hope will be pan U.S. and European Union joint action plan to cut greenhouse gas emissions from aircraft. Specifically the group announced the Atlantic Interoperability Initiative to Reduce Emissions or AIRE

    Additionally, the FAA announced that their agency would be renamed the 'American Institute for Regulation of Pilot Licensing and Aeronautical Navigation and Engineering' (AIRPLANE) to satisfy new federal requirements for cutesy acronyms.

  5. Re:Lead In Fuels? by TopSpin · · Score: 4, Informative

    What about the lead thats in General Aviation Fuel? Are they doing anything to reduce that? To be clear; the fuel burned by jets is not leaded. This accounts for the vast bulk of aviation fuel consumption. Leaded fuel is used by most piston engined aircraft.

    --
    Lurking at the bottom of the gravity well, getting old
  6. Yes by BBCWatcher · · Score: 3, Interesting

    There has been literally decades of research, and research is ongoing. There's no single good answer. High compression piston aircraft engines may be able to run on fuels with other additives, but all the reformulations discovered so far are much more toxic than the current 100LL formulation.

    Some of the technical solutions include shipping 100LL without the lead (which mid-compression engines can probably run OK), electronic ignition systems, and diesel (jet fuel) retrofit with new engines. Whole new, small aircraft, particularly from Diamond Aircraft, run on Jet-A. The lead additive (TEL) is getting more expensive, so price is encouraging some movement in this direction anyway, particularly outside the U.S.

    It's important to keep some perspective here, though. The amount of lead released into the atmosphere by piston aircraft engines is incredibly miniscule, and it's not released in the ways automobiles did (i.e. near the ground, in lung-concentrated ways). There are about 5,000 public airports in the U.S., and the vast majority of those have very limited numbers of aircraft operating on the ground for very brief periods of time. So unless you live on a taxiway at a busy small aircraft airport, and breathe deeply for some years, you're OK.

    There are many, many places where environmental protection money would be more wisely spent. The simple act of burning coal, for example, is incredibly, vastly more dangerous than anything the entire piston aircraft engine fleet could do. That said, it would probably make sense for the government to give the engine industry (mainly Lycoming and Continental) a bit of a nudge, telling them to find any solution they wish to stop producing new aircraft engines that run only on leaded fuels by a date certain (say, 10 years out). In all probability they can recertify with a combination of electronic ignition and the same 100LL formulation but without TEL, and they can do that relatively inexpensively. If the feds made every aircraft owner who replaced their engines eligible for fuel tax rebates for a period of, say, 5 years from date of installation, that'd probably get the job done to get the fleet converted. But nobody is in a rush to do this because nobody at the EPA sees a public health problem here.

    1. Re:Yes by GooberToo · · Score: 3, Insightful

      In all probability they can recertify with a combination of electronic ignition and the same 100LL formulation but without TEL, and they can do that relatively inexpensively. If the feds made every aircraft owner who replaced their engines eligible for fuel tax rebates for a period of, say, 5 years from date of installation, that'd probably get the job done to get the fleet converted. But nobody is in a rush to do this because nobody at the EPA sees a public health problem here.

      But its a catch-22. Aviation piston engines cost anywhere from $18,000 - $60,000 to replace, as is. No tax rebate is going to cover the cost of engine replacement; especially once you add in the cost of a newly certified engine technology. Certifying an engine with the FAA easily costs $1,000,000 and up. Because the FAAs moto is, "We're not happy unless you're not happy", they keep various technologies unavailable simply because the price for entry is far, far too high, despite it being a proven technology. Worse, most of their regulations are based about 1940s and 1950s technology assumptions; as that's the technology base most of the guys that created the regulations could relate to. The Beech Starship is a classic example. They truly innovated but the FAA tied them up with red tape for so long during the certification process, it was cheaper for Beech to buy back every plane and DESTROY THEM than it was to hope they could make their money back on their investment.

      Heck, manual adjustment of the air/fuel mixture is common place in GA. Something as common as fuel injection is still considered a big step up and the fuel inject is decades behind what is commonly found in cars. And, even with fuel injection, manual control of the air/fuel mixture is still the norm.

      Another example is something as simple as a clock. The FAA regulations require a certified clock (think of time/distance navigation where time is very important for safe operation). That made sense during the 1940s and 1950s when a precise time piece was uncommon. Likewise, it made sense as a clock to be mounted is required to maintain accuracy with various vibration and pressure changes, and would be hard to find back then. These days, the FAA certified clocks cost hundreds of dollars yet are less accurate, BY FAR, than what most people can pick up for $5 bucks at the local dollar store. Some of the old certified clocks will actually lose a minute or more over a four hour flight. And they can get worse with age. Worse yet, they are renowned for their unreliability. As a result, most pilots violate the regulations because they want something that is accurate, safe, and reliable rather than something that is certified. And yes, the FAA does ding people for using something that is safe and reliable rather than something that is certified.

      Long story short, the ONLY thing preventing piston airplanes from becoming faster, cheaper, safer, and more environmentally friendly is the FAA. If the goverment would clean house and restructure the FAA, forcing them to revamp their certification process, the world of air travel would be a much, much better place.

  7. Re:impact by DieByWire · · Score: 4, Interesting

    It's actually really surprising how much airlines currently *don't* do to optimize fuel costs....

    Actually, they go to great lengths to minimize fuel burn. The reason they're often not at optimum altitude or speed is due to ATC constraints. At most (not all) airports, you'll have a much earlier than optimum descent from cruise altitude, followed by being high on the downwind leg (leaving enough space for departing aircraft to get out under the arrivals), followed by a tight, slam dunk, high drag approach or a loooong downwind while you do a low level fuel annihilation run due to the amount of traffic arriving.

    Oceanic routes have huge spacing requirements due to the lack of radar coverage. Because of that, it's often difficult to get a clearance to a new altititude while over the pond. It's not uncommon to cross the ocean at one altitude for the entire crossing, even though the optimum altitude will go up as the aircraft gets lighter.

    So, airlines do the best they can with the constraints they face. Improving the ATC system will be a big help.

    --
    Never shake hands with a man you meet in a fertility clinic.
  8. Re:Happy to see government agencies doing right by vought · · Score: 3, Insightful

    I loath flying in the commuter planes; slow, noisy, cramped.

    Unfortunately for you, (and me) most flyers care more about schedule convenience, and perceive all aircraft as the same noisy, cramped environment.

    I would think that larger planes would also improve efficiency.

    Sure, I'd prefer to stuff medium to high density routes with nothing but 767s, 787s and 777s flying 1-2x a day instead of the 5-6 flights each day between say, SJC and DFW. But it ain't gonna happen. It's easier to sell a ticket on a 50-seat Canadair to someone who wants to leave in mid-afternoon than to convince them to wait several hours to take a more efficient, larger jet. And the efficiencies of scale aren't all that bad for small jets, either.

    (Even when I did try to shoehorn my schedule around so I could fly United's 777 service instead of yet another aging 737 or claustrophobic 757, United screwed up and I got to watch the 777 push back as the jet I was in taxied to the gate over an hour late. I ended up on the smelly, cramped 737 I was trying to avoid.)

    Most people don't fly high density routes because the hub-and-spoke system puts lots of people on lots of planes going to a handful of airports. It's easier to service the system with lots of small to medium sized airplanes.

  9. Re:I'm all for cleaning up by Swoopy · · Score: 3, Informative

    Stop speculating.
    The waste per passenger, but most of all the method and place (high in the sky) of combustion ensure that greenhouse effects of aviation fuel are far worse than those of motorcars' combustion engines.
    http://www.csmonitor.com/2005/0210/p14s02-sten.htm l
    If you're planning to travel, want to do it the way that's most environmentally friendly and the consideration whether to drive instead of fly is a realistic option (e.g. both take about a day of travel, no large body of water to cross), then drive.

  10. Re:Cant they wait... by Walt+Dismal · · Score: 3, Funny

    Call me crazy, but I think we could reduce air pollution a lot by banning coal-fueled aircraft engines and use horses instead. It just might work.

  11. Hurry Up and Wait for Inefficiency by Doc+Ruby · · Score: 4, Interesting

    If they just improved their flight scheduling infosystems to eliminate wasteful delays and wasteful rushing to catch up, they'd burn a lot less fuel per mile traveled.

    How many times have we arrived above an airport, just to fly in circles until the terminal is ready to let us get to the gate? How long have we spent burning fuel on the runway, waiting for our turn to take off? All that extra fuel burned to go extra miles between our points.

    And then the pilot tells us they'll pour on the speed to catch up to schedule, or get us ahead of schedule - so we have to wait longer for a gate to open when we arrive. That extra airspeed might improve their ontime arrivals/departures stats, but once out of the maximum efficiency range, that 4th power of wind resistance per area drag really multiplies the inefficiency out of the engine's peak efficiency RPM.

    But if their logistics just mapped the arrivals/departures to the capacity of the airports, most of that waste would be unnecessary. I wouldn't be surprised to see >10% fuel efficiency gained right there, plus the extra efficiency from less refueling infrastructure.

    --

    --
    make install -not war

  12. Please, take your head out of the sand... by WIAKywbfatw · · Score: 4, Informative

    Great post. If you want to hide your head in the sand, that is. Let me just shatter the myth that you're perpetuating in your first paragraph.

    1. The US is by far the biggest polluter per capita.

    Compare apples with apples, instead of of apples with oranges, by looking at per capita figures. The CIA World Factbook lists the population of China as 1,321,851,888 (July 2007 est.) and the population of the US as 301,139,947 (July 2007 est.).

    You wouldn't compare the carbon dioxide emissions output of the US with that of a tiny nation like Bermuda, so play fair and use the most sensible measure to compare who's contributing how much.

    A quick mental calculation will show you that, in carbon dioxide terms alone, the US produces four times as much domestically as China does.

    2. China makes goods for the US, not the other way around.

    All those goods that China makes that the US consumes (clothing, electronics, etc) have an associated cost in terms of carbon dioxide and other pollution. But, of course, the figures that you've latched onto don't attribute those to the country of consumption, only to the country of origin.

    Put simply, when a Chinese factory makes something that an American will buy, it's at least partially (if not fully) pollution caused by the American consumer. So, a large chunk of the pollution caused by China, etc is due to the US (and other consumer nations) as well.

    The US has five percent of the world's population. The US consumes roughly 25-30 percent of the world's goods, and hence is responsible for 25-30 percent of the pollution. To sustain everybody on the planet at the current US level of consumption would take five to six Earth's worth of resources and create a similar amount of pollution.

    Now do you see why the US plays such a big part in this and should be taking positive, proactive steps to try to address the issues instead of trying to shift the blame to others?

    As for your closing complaint that "This is more government micromanagement that will do nothing but further bring us down", well, I could not disagree more. The free market alone will never make the necessary steps to do what's necessary by itself, no matter what you might think. Want an example? Then just look at how car manufacturers fought tooth and nail against mandatory installation of seatbelts in cars. Same shit, different decade, that's all.

    Please take your head out of the sand for a minute to think about it.

    --

    "Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
  13. Re:Lead In Fuels? by Gordonjcp · · Score: 4, Informative

    Fuel should be leaded!

    Indeed it should. We'd be a lot better off without the filthy menace of unleaded petrol pumping benzene vapours into the atmosphere. Lead is toxic - massively toxic in certain compounds (lead acetate was what did in the Romans, from making a sweet by boiling wine in lead pots), but practically inert in the form that comes out of petrol engine exhausts. Furthermore, the lead carbonate that you get mostly settles out on the first 18" or so of exhaust pipe.

    By comparison, unleaded petrol uses benzene instead of tetraethyl lead as an anti-knock agent, which is highly toxic and carcinogenic. Then on top of that we've got the eco-disaster that is catalytic converters, belching out dense clouds of hydrogen sulphide unless they're run at extremely high exhaust gas temperatures - which produces massive amounts of nitrogen oxides. By a nasty little quirk, catalytic converters make car exhaust *more* polluting when driven at low speeds (such as in towns, where they'd be most useful) than when driven at motorway speeds.