I have been reading about 100LL AVGAS. The EPA and therefore the FAA wants to ban 100LL due to lead content, in 2010.
What do you guys think?
Chris
What do you guys think?
Chris
100LL AVGAS to be phased out in 2010!
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might force the engine manufactures to come out of the 1930's
Originally Posted By: wileyE
might force the engine manufactures to come out of the 1930's
What makes you say that?
Unleaded racing fuels are very, very toxic. More so than leaded racing fuels. For power production, we use leaded for uniformity, not for some kind of design problem.
100LL is consistent for safety. In flight, safety is a huge concern for the pilot/passengers as well as those below. A whole lot different than slowing to the side of the road way.
I don't see that anyone has found a reasonable alternative that provides the consistency of 100LL. If there is data that says otherwise, I'd be interested in links to it.
might force the engine manufactures to come out of the 1930's
What makes you say that?
Unleaded racing fuels are very, very toxic. More so than leaded racing fuels. For power production, we use leaded for uniformity, not for some kind of design problem.
100LL is consistent for safety. In flight, safety is a huge concern for the pilot/passengers as well as those below. A whole lot different than slowing to the side of the road way.
I don't see that anyone has found a reasonable alternative that provides the consistency of 100LL. If there is data that says otherwise, I'd be interested in links to it.
why do AC recip. engines still require lead but automotive engines haven't needed it for 30 years?
Originally Posted By: tom slick
why do AC recip. engines still require lead but automotive engines haven't needed it for 30 years?
The EPA mandated that lead not be present in street fuel.
As for 100LL, it's consistent across the country and at different altitudes.
Put lead in a car now, and it will ruin the cat.
why do AC recip. engines still require lead but automotive engines haven't needed it for 30 years?
The EPA mandated that lead not be present in street fuel.
As for 100LL, it's consistent across the country and at different altitudes.
Put lead in a car now, and it will ruin the cat.
Is the lead what makes it consistent?
Originally Posted By: tom slick
why do AC recip. engines still require lead but automotive engines haven't needed it for 30 years?
I don't really know, but there are still a LOT of 50+ year old planes out there flying, and if they gotta have lead, then they gotta have it, period.
I'm all for helping the environment but I hate the EPA.
why do AC recip. engines still require lead but automotive engines haven't needed it for 30 years?
I don't really know, but there are still a LOT of 50+ year old planes out there flying, and if they gotta have lead, then they gotta have it, period.
I'm all for helping the environment but I hate the EPA.
The only ones that really need it are the high performance turbocharged engines. However, a lot of low performance aircraft were certified on 100/130 or 100LL. The real old ones were certified for 80/87 that is no longer made. Each one needs an STC to run on auto gas. Try and buy straight unleaded auto gas with no ethanol in California, so we are still stuck using leaded avgas in planes that dont really need it.
No matter what the EPA says, only about 30% of our current piston fleet can use low octane fuel. And, those numbers are in decline. Current production engines are biased towards higher octane needs.
One possible answer is synthetic Avgas.
http://www.aviationweek.com/aw/blogs/bus...d1-d72c04948405
One possible answer is synthetic Avgas.
http://www.aviationweek.com/aw/blogs/bus...d1-d72c04948405
wow, that will ground all the historic restoration aircraft like the connies, DC6 and DC7 that are still flying. Also all the CAF aircraft and those Martin Mars flying boats the Canuks use for fire bombers.
R-2800s and 3350s won't run on the lower octane stuff.
R-2800s and 3350s won't run on the lower octane stuff.
When you say aircraft engines will come out of the 1930's, I completely agree. Regardless of the quality of 100LL, a typical new engine in a light, general aviation aircraft is really from a 1930's design and engineering mentality. They're huge displacement engines making low amounts of power. Compared to the amazing advances in automotive engines and turbine engines, the piston aircraft world has a long, long way to come to even reach 1970's technology.
The lawyers are likely to blame. Everything in aviation is overly expensive and has to be "certified" to be used. Right down to the $50 light bulbs that are $0.50 for your Chevrolet (and likely exactly the same) but the liability factor brings the price up. Because everything needs certification, it takes a long time to make it "airworthy" so it becomes easier to just keep on making what has worked and was certified before. This is to the point that if you invented and NDB, or a lycoming engine for that matter, it might not pass certification today because by today's engineering standards, it's old technology. It only keeps being used because it's proved technology. But this means little advancement.
Getting back to the topic of the thread, I have heard from a chemical engineer that 100LL is actually a very crude, poorly refined product compared to other fuels in use today. But since the aviation market demands old and low-refined fuels to go with its old style engines, they keep making it.
100LL's demise probably will cause a new era of conversion kits to allow most light aircraft to use 87 octane pump gas. Hopefully it becomes much cheaper and more easily accessible. As prices rise, the future may be with these diesel conversions.
The lawyers are likely to blame. Everything in aviation is overly expensive and has to be "certified" to be used. Right down to the $50 light bulbs that are $0.50 for your Chevrolet (and likely exactly the same) but the liability factor brings the price up. Because everything needs certification, it takes a long time to make it "airworthy" so it becomes easier to just keep on making what has worked and was certified before. This is to the point that if you invented and NDB, or a lycoming engine for that matter, it might not pass certification today because by today's engineering standards, it's old technology. It only keeps being used because it's proved technology. But this means little advancement.
Getting back to the topic of the thread, I have heard from a chemical engineer that 100LL is actually a very crude, poorly refined product compared to other fuels in use today. But since the aviation market demands old and low-refined fuels to go with its old style engines, they keep making it.
100LL's demise probably will cause a new era of conversion kits to allow most light aircraft to use 87 octane pump gas. Hopefully it becomes much cheaper and more easily accessible. As prices rise, the future may be with these diesel conversions.
Originally Posted By: Tremo
Also all the CAF aircraft..
What are CAF aircraft?
Also all the CAF aircraft..
What are CAF aircraft?
Originally Posted By: Gannet167
Originally Posted By: Tremo
Also all the CAF aircraft..
What are CAF aircraft?
http://www.commemorativeairforce.org/
Originally Posted By: Tremo
Also all the CAF aircraft..
What are CAF aircraft?
http://www.commemorativeairforce.org/
Originally Posted By: tom slick
http://www.commemorativeairforce.org/
When did they change their name?
http://www.commemorativeairforce.org/
When did they change their name?
Originally Posted By: Gannet167
...
Getting back to the topic of the thread, I have heard from a chemical engineer that 100LL is actually a very crude, poorly refined product compared to other fuels in use today. But since the aviation market demands old and low-refined fuels to go with its old style engines, they keep making it.
100LL's demise probably will cause a new era of conversion kits to allow most light aircraft to use 87 octane pump gas. Hopefully it becomes much cheaper and more easily accessible. As prices rise, the future may be with these diesel conversions.
100LL is hardly a poorly refined product. It is primarily isopariffins and aromatics, the same light alkylates used in reformulated automotive gasoline and toluene with a shot of butane to adjust vapor pressure.
Some non-turbocharged piston engines originally certified for 100/130 to have Supplemental Type Certificates to run legally on unleaded automotive gasoline. Unfortunately, that is no longer an option due to ethanol mandates. E10 does not qualify. The same goes for antique aircraft that were designed for 80/87, no longer made, which was probably the "crude" straight-run gasoline that he may have been referring to.
Aircraft diesels have not gotten very far, yet. Thielert has turned out to be an expensive disaster. Maybe that will change with further development.
...
Getting back to the topic of the thread, I have heard from a chemical engineer that 100LL is actually a very crude, poorly refined product compared to other fuels in use today. But since the aviation market demands old and low-refined fuels to go with its old style engines, they keep making it.
100LL's demise probably will cause a new era of conversion kits to allow most light aircraft to use 87 octane pump gas. Hopefully it becomes much cheaper and more easily accessible. As prices rise, the future may be with these diesel conversions.
100LL is hardly a poorly refined product. It is primarily isopariffins and aromatics, the same light alkylates used in reformulated automotive gasoline and toluene with a shot of butane to adjust vapor pressure.
Some non-turbocharged piston engines originally certified for 100/130 to have Supplemental Type Certificates to run legally on unleaded automotive gasoline. Unfortunately, that is no longer an option due to ethanol mandates. E10 does not qualify. The same goes for antique aircraft that were designed for 80/87, no longer made, which was probably the "crude" straight-run gasoline that he may have been referring to.
Aircraft diesels have not gotten very far, yet. Thielert has turned out to be an expensive disaster. Maybe that will change with further development.
What exactly makes 100LL required, vs using 93 auto gas? Is the lead for lubricating the valves? They're not really high compression engines when compared to auto engines using lower octane fuel.
Someone should just make a small, cheap turbine replacement for pistons.
Someone should just make a small, cheap turbine replacement for pistons.
Originally Posted By: Tremo
wow, that will ground all the historic restoration aircraft like the connies, DC6 and DC7 that are still flying. Also all the CAF aircraft and those Martin Mars flying boats the Canuks use for fire bombers.
R-2800s and 3350s won't run on the lower octane stuff.
I saw the Martin Mars working this summer with all the fires in Calif. It watered up in Lake Shasta and it is a good size plane. Looks real nice.
wow, that will ground all the historic restoration aircraft like the connies, DC6 and DC7 that are still flying. Also all the CAF aircraft and those Martin Mars flying boats the Canuks use for fire bombers.
R-2800s and 3350s won't run on the lower octane stuff.
I saw the Martin Mars working this summer with all the fires in Calif. It watered up in Lake Shasta and it is a good size plane. Looks real nice.
Wouldn't the aluminum heads have to have valve seat inserts any way?
Originally Posted By: Gannet167
What exactly makes 100LL required, vs using 93 auto gas? Is the lead for lubricating the valves? They're not really high compression engines when compared to auto engines using lower octane fuel.
Someone should just make a small, cheap turbine replacement for pistons.
What do you mean they're not "high compression"? Those old radials are all supercharged! With 100LL. a Wright R-3350 can be run up to 52 inches of manifold pressure. But, those engines were designed to run on the no longer available 115/145, where they could boost them to 59 inches. That's a LOT of supercharger boost. At 59 inches, a 3350TC put out like 3400 horsepower at 2900 RPM. Same engine on 100LL and 52 inches is like 2800 horse.
Airplane engines, unlike car motors, are designed to produce all their power at LOWER RPMs. They do not turn 5500 to 6500 RPM. More like 3000. Most are undersquare strokers.
What exactly makes 100LL required, vs using 93 auto gas? Is the lead for lubricating the valves? They're not really high compression engines when compared to auto engines using lower octane fuel.
Someone should just make a small, cheap turbine replacement for pistons.
What do you mean they're not "high compression"? Those old radials are all supercharged! With 100LL. a Wright R-3350 can be run up to 52 inches of manifold pressure. But, those engines were designed to run on the no longer available 115/145, where they could boost them to 59 inches. That's a LOT of supercharger boost. At 59 inches, a 3350TC put out like 3400 horsepower at 2900 RPM. Same engine on 100LL and 52 inches is like 2800 horse.
Airplane engines, unlike car motors, are designed to produce all their power at LOWER RPMs. They do not turn 5500 to 6500 RPM. More like 3000. Most are undersquare strokers.
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