For years now fossil fuel passenger vehicles have been under emissions control reduction policies (stricter over time) by various government agencies. Then it was heavy trucks, heavy construction machinery, and such. Costs and reliability issues have arisen from these emission control mandates. So, when are these same agencies going to start requiring some type of emissions control devices in quantity on fossil fueled aircraft?
Aircraft pollution emission control
- Thread starter Electromotive
- Start date
As you probably already know there are some rather strict criteria in place for gas turbine engines.
www.epa.gov
It's good to understand that modern engines are far more efficient, produce lower NOx emissions and have far more complete combustion than the engines of just a few years ago.
It's also good to understand that modern jet transport aircraft achieve fantastic passenger MPG, often well over 100pmpg, and some aircraft top 120. You'd have to work really hard to do that well with a Prius. As driving takes 25% more miles than flying (on average).
The GE passport engine on the Global 7500 is actually white ceramic inside. It runs so cleanly, you can't smell the exhaust and the white components don't discolor.
Regulations for Greenhouse Gas Emissions from Aircraft | US EPA
EPA and the National Highway Traffic Safety Administration (NHTSA) are taking coordinated steps to enable the production of a new generation of clean vehicles, through reduced greenhouse gas (GHG) emissions and improved fuel use from onroad vehicles.
www.epa.gov
It's good to understand that modern engines are far more efficient, produce lower NOx emissions and have far more complete combustion than the engines of just a few years ago.
It's also good to understand that modern jet transport aircraft achieve fantastic passenger MPG, often well over 100pmpg, and some aircraft top 120. You'd have to work really hard to do that well with a Prius. As driving takes 25% more miles than flying (on average).
The GE passport engine on the Global 7500 is actually white ceramic inside. It runs so cleanly, you can't smell the exhaust and the white components don't discolor.
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I think the first attempt was started 35 years ago. Commercial jet used to leave trailing brown smoke during take off and flying to altitude. I believer laws were passed to eliminate that and jet engines were designed to be more efficient, which at least minimized the acid rain caused by the unburnt fuel. I'm not sure if any thing done from a legal standpoint since then but, jet engine efficient has improved, I've read.
As far as aircraft piston engines having catalysts, there are actually a few experimental Honda based engines that retain the cat. They, of course, require unleaded fuel. They have had a few problems with melt down and exhaust clogging. Probably not the best idea...
Here is a Viking (Honda based) aircraft engine with cat:
Here is a Viking (Honda based) aircraft engine with cat:
I had to do it:
Someone please post a link to the no carbon emission Ammonia fueled jet airliner that was on some thread here the other day. I could not find it.
Also note that hydrazine would also work as a zero emission fuel, but would probably weight about the same for the same energy content, though it probably would be more compact. I also wonder which of the two would be easiest to handle, safest, and most cost effective. That is an area of the two that I have no experience to draw any conclusions about.
Note that if either of those are ever actually put into use, simple, but big, emergency cold water showering systems to dilute leaks would be a very good idea to have around.
One thing, such systems would rule out emergency fuel dumps over populated land.
Also note that hydrazine would also work as a zero emission fuel, but would probably weight about the same for the same energy content, though it probably would be more compact. I also wonder which of the two would be easiest to handle, safest, and most cost effective. That is an area of the two that I have no experience to draw any conclusions about.
Note that if either of those are ever actually put into use, simple, but big, emergency cold water showering systems to dilute leaks would be a very good idea to have around.
One thing, such systems would rule out emergency fuel dumps over populated land.
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We've talked about this regarding other topics, but there may be a mandate for certain biofuels because the reduce certainly polluting emissions, and often by a lot.
There are already very strict emissions regulations on jet engine aircraft. Noise regulations are very exacting.
Look, airlines run the airplanes, on average, for 10 hours per day. Saving fuel, when fuel is over 40% of your entire operations cost, more than labor, is big.
Aircraft operators, like airlines, are very into saving fuel - because the fuel costs more than the airplanes, which cost between $100 and $350 million each.
So, reduced APU usage, single engine taxi, route and altitude optimization are all saving fuel. Emissions are managed by that savings.
If you’re talking about piston airplanes, they use so little fuel compared with automobiles, about 0.14%, that regulating them accomplishes nothing, really. Cars use nearly a thousand times the fuel, annually, that piston airplanes do, so, there is very little gain to be had by regulating piston airplanes.
And at $6.00/gallon, most piston airplane owners and operators are into saving fuel as well…
Look, airlines run the airplanes, on average, for 10 hours per day. Saving fuel, when fuel is over 40% of your entire operations cost, more than labor, is big.
Aircraft operators, like airlines, are very into saving fuel - because the fuel costs more than the airplanes, which cost between $100 and $350 million each.
So, reduced APU usage, single engine taxi, route and altitude optimization are all saving fuel. Emissions are managed by that savings.
If you’re talking about piston airplanes, they use so little fuel compared with automobiles, about 0.14%, that regulating them accomplishes nothing, really. Cars use nearly a thousand times the fuel, annually, that piston airplanes do, so, there is very little gain to be had by regulating piston airplanes.
And at $6.00/gallon, most piston airplane owners and operators are into saving fuel as well…
That is interesting--is there a difference between piston and turbine? I mean, I know there is... but aren't most piston engines running leaded gas still?
Perhaps this isn't an issue with turbines but maybe it is with the piston setups. Then again, down in the noise, given much lighter usage, but not really the issue. The big jets, if they really do hit 100+mpg in service, clearly aren't part of the problem. [add in the lower rate of accidents per mile and one should almost encourage air travel by comparison.]
Perhaps this isn't an issue with turbines but maybe it is with the piston setups. Then again, down in the noise, given much lighter usage, but not really the issue. The big jets, if they really do hit 100+mpg in service, clearly aren't part of the problem. [add in the lower rate of accidents per mile and one should almost encourage air travel by comparison.]
It averages that much. That doesn't mean it's ideal. Takeoffs use a lot of fuel, so obviously more aircraft flying shorter distances will bring down the average. Another is that the efficiency comes from cruising at high altitude. And aircraft engines are generally operating closer to maximum power than most cars. Plus the way airports are set up, the passenger will still need to access ground transportation.
It's actually pretty simple to achieve higher efficiency in ICE cars. Just make them smaller and lighter, with smaller engines operating closer to maximum power and maximum thermal efficiency. But how many people want cars that feel unsafe next to larger, heavier vehicle and take forever to get up to freeway speeds? Plus have low top speeds?
If we could get full loads, electric trains could probably be more efficient than aircraft in equivalent passenger MPG. Especially if we moved to a lot of the stuff that being done for aircraft such as use of composites and other lighter materials.
Not sure if I agree, I mean, just make it a hybrid. Wife's Camry is supposedly around 40% efficient around 2k rpm, and I think the ECU is going to do what it can to eek out what it can. Use the battery as an averaging device, that way if the engine has to run, it can be run under load, dump power into the battery, the shut off and draw off. All a numbers game, in determining what is the best approach. Apparently it works, around town with low a/c usage she was (is?) getting low 60's for mpg. [No idea yet what winter and high speed highway cruising would do though.] And it is still something like 200hp if WOT is required.
But I do mostly agree, uber small engine pushing as little as possible, live with low power to weight, should reap mpg. And you're right, I wouldn't put with it either.
Well yeah. A hybrid works by supplementing the power of the engine. And using an underpowered engine isn't a strict requirement (think Ferrari), but it generally helps when trying to improve efficiency. Still - that's a balance. There's a lot of stuff that's done too including regenerative braking. Still - most hybrids have high fuel economy at freeway speeds, and that's not necessarily a matter of it being a hybrid, but from using a more efficient engine. If that was your sole concern, a more efficient engine while scrapping all the weight of the battery and hybrid drivetrain would probably be more efficient.
Another thing about commercial aircraft is that they operate most of their time cruising, so obviously they're geared to be most efficient doing that. But we need our cars to operate in a real world where they might even need to stop at every block and then go on the freeway. Our cars have to do everything acceptably rather than just do one thing well.
Yes, but the lead content is 50% or less of what it was in leaded auto gas from decades ago.
That may be true but it's still putting lead into the air.
I question this. The standard avgas is 100LL, with "LL" = "low lead", but that's only in comparison with past aviation gasoline grades. Read years ago that even 100LL has four times the lead of the highest-lead automotive gasoline ever sold to the public, which was Sunoco 260.
The US EPA wanted to phase out 100LL 40 years ago in favor of unleaded. The light aircraft industry dug in its heels, nothing was done, and the same aviation engines requiring the same leaded fuel remained in production.
This does not make the industry look good, and now it is becoming a target for the greens. Massachusetts has proposed a $1,000 landing fee for noncommercial private aircraft at airports there for environmental reasons. That's more about carbon, but the lead issue doesn't help.
Unleaded Fuels Testing Temporarily Suspended, Next Steps Being Developed
By Megan Esau, EAA Assistant Editor
July 22, 2018 - The Piston Aviation Fuels Initiative (PAFI) is
currently considering next steps for the development of unleaded fuels
for the GA aircraft fleet after the FAA announced in June that it was
temporarily suspending testing of the two fuels in the program, giving
the fuel developers an opportunity to address some of the findings
from the exhaustive testing.
Those two fuels, from Shell and Swift, have been studied since 2016
and were the final candidates of 19 fuels to advance to full-scale
engine and flight testing.
PAFI was developed as a collaborative program between the FAA and the
aviation and petroleum industries to find a satisfactory high-octane
unleaded replacement for 100LL avgas, which is currently used by the
vast majority of piston aircraft in the U.S. GA fleet.
Full-scale engine and aircraft testing has been temporarily suspended
to allow time for fuel developers to assess and potentially address
differences between the unleaded fuels and 100LL. As satisfactory
mitigations to these differences are developed PAFI will continue to
evaluate the fuels further.
In the meantime, PAFI, through the FAA, has also reached out to other
fuel developers with proposed fuels that emerged after the program was
established, or who had previously declined to participate in the
initial competitive process, to determine if further examination of
any of those fuels is warranted.
“The collaborative FAA-industry PAFI program has done exactly what it
was designed to do — take promising fuels and subject them to
rigorous, standardized materials, engine, fuel system, and aircraft
testing, developed and agreed to by the full breadth of industry, to
determine their performance characteristics and any limitations they
might pose in satisfying the general aviation fleet,” said Doug
Macnair, EAA’s vice president of government relations. Macnair has
been EAA’s representative to the PAFI program from its inception.
He said finding a fuel that safely and cost-effectively meets the
requirements of the GA fleet, and has the confidence of aircraft
owners as well as engine and airframe manufacturers, is PAFI’s
priority, and it does not intend to introduce fuels to the market that
do not meet these goals.
“What this process tells us is what EAA has maintained for the past 30
years: Finding a high-octane unleaded avgas replacement is a daunting
technological challenge,” Macnair said. “EAA joins everyone in the
industry in welcoming all potential solutions to take part in this
standardized and industry-accepted testing protocol, so together we
can find the best and broadest possible solution for the GA fleet.”
Representatives from Shell (Booth 450 in the Main Aircraft Display)
and Swift Fuels (Booth 461 in the Main Aircraft Display) are
exhibiting at AirVenture and available to answer questions about their
proposed fuels.
The PAFI program’s efforts to evaluate high-octane unleaded
alternatives to 100LL will continue into the future and will include
facilitating the eventual deployment of any future fuel.
Full commercialization and deployment of a replacement for 100LL will
only occur through the collaboration of the aviation and petroleum
industries, along with environmental and aviation regulators. Macnair
said the strength of the PAFI program is in bringing all of the
necessary resources and knowledge together to work toward a common
understanding and potential solutions.
By Megan Esau, EAA Assistant Editor
July 22, 2018 - The Piston Aviation Fuels Initiative (PAFI) is
currently considering next steps for the development of unleaded fuels
for the GA aircraft fleet after the FAA announced in June that it was
temporarily suspending testing of the two fuels in the program, giving
the fuel developers an opportunity to address some of the findings
from the exhaustive testing.
Those two fuels, from Shell and Swift, have been studied since 2016
and were the final candidates of 19 fuels to advance to full-scale
engine and flight testing.
PAFI was developed as a collaborative program between the FAA and the
aviation and petroleum industries to find a satisfactory high-octane
unleaded replacement for 100LL avgas, which is currently used by the
vast majority of piston aircraft in the U.S. GA fleet.
Full-scale engine and aircraft testing has been temporarily suspended
to allow time for fuel developers to assess and potentially address
differences between the unleaded fuels and 100LL. As satisfactory
mitigations to these differences are developed PAFI will continue to
evaluate the fuels further.
In the meantime, PAFI, through the FAA, has also reached out to other
fuel developers with proposed fuels that emerged after the program was
established, or who had previously declined to participate in the
initial competitive process, to determine if further examination of
any of those fuels is warranted.
“The collaborative FAA-industry PAFI program has done exactly what it
was designed to do — take promising fuels and subject them to
rigorous, standardized materials, engine, fuel system, and aircraft
testing, developed and agreed to by the full breadth of industry, to
determine their performance characteristics and any limitations they
might pose in satisfying the general aviation fleet,” said Doug
Macnair, EAA’s vice president of government relations. Macnair has
been EAA’s representative to the PAFI program from its inception.
He said finding a fuel that safely and cost-effectively meets the
requirements of the GA fleet, and has the confidence of aircraft
owners as well as engine and airframe manufacturers, is PAFI’s
priority, and it does not intend to introduce fuels to the market that
do not meet these goals.
“What this process tells us is what EAA has maintained for the past 30
years: Finding a high-octane unleaded avgas replacement is a daunting
technological challenge,” Macnair said. “EAA joins everyone in the
industry in welcoming all potential solutions to take part in this
standardized and industry-accepted testing protocol, so together we
can find the best and broadest possible solution for the GA fleet.”
Representatives from Shell (Booth 450 in the Main Aircraft Display)
and Swift Fuels (Booth 461 in the Main Aircraft Display) are
exhibiting at AirVenture and available to answer questions about their
proposed fuels.
The PAFI program’s efforts to evaluate high-octane unleaded
alternatives to 100LL will continue into the future and will include
facilitating the eventual deployment of any future fuel.
Full commercialization and deployment of a replacement for 100LL will
only occur through the collaboration of the aviation and petroleum
industries, along with environmental and aviation regulators. Macnair
said the strength of the PAFI program is in bringing all of the
necessary resources and knowledge together to work toward a common
understanding and potential solutions.
I'll take lead in the air over radioactive isotopes any day.
