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FAA: Unleaded fuel by 2018


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3 hours ago, Mooneymite said:

Actually my post concerning electric planes was not motivated by any sort of environmental zealatry, but just from a performance standpoint.

Can you imagine electric flight where the ellectricity is beamed to the aircraft.  No batteries, no avgas, no internal combustion engine.  Just a smooth, lightweight servoed electric motor propelling a next-gen efficient Mooney!

Well... let me dream.  :rolleyes:

Hey, most of those electric power transmission schemes involve microwave beams.  For 100 hp, you're talking 75 kilowatts of microwave power.  That's the output of 75,000 microwave ovens :unsure: a little nervous about that...

On the other hand, you'd have no problem with in flight snacks.  Popcorn anyone?

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Its interesting to think about where we will be in 50 years considering the advances in all other fields other than aviation, which seems to be stuck around 1960. The internal combustion engine hasn't really changed much since the 1900s in reality. We modify the control mechanisms (fuel, electrics, etc) but the basic piston going up and down remains the same.

Jet power is the only thing that changed the SAFETY equation for the airlines. Reliability from failure of the old round motors was the biggest  safety improvement for the traveling public in the history of aviation.  And that was almost 70 years ago.

Where will we really be in 50 years?

Here's a question I have (I know a little off subject, apology offered) -

Who's making the money in wind farms?  Has anyone ever tried to find out about the financials of a wind farm investment? It can't be found.  Where's the money being made? Lots of building but where's the money? What's the old saying? "Follow the money?"

True cost per KW produced is yet another factor.

Its been said that a wind generator will never recover the TOTAL cost to produce the unit.

Lots of interesting questions.   Sorry for the drift it just comes to mind at odd times. 

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3 minutes ago, Mooneymite said:

I've always heard that Wind Generators were designed to generate tax credits, not electricity.

However, that may be an urban myth.  :ph34r:

There was a time early in development that wind turbines did consume more energy to build than they would produce in their lifetime, but last time I checked that is not the case anymore.  As with anything, economies of scale prevail not to mention the improved materials available now vs 20 or 30 yrs ago.

Now I have a question since this thread started debating leaded gasoline.  What good does the lead serve?  My understanding, as a young guy who never lived through the leaded generation, that the lead lightly coats the iside of the cylinder to make the valves seal better.  What would be the harm in not using leaded gas in our engines?  I had a '65 Ford Falcon that was built in the leaded generation that I never burned leaded gas in and it ran fine.  My cherokee had the STC to run unleaded mogas and best I remember there were no changes except paperwork.

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35 minutes ago, bob865 said:

There was a time early in development that wind turbines did consume more energy to build than they would produce in their lifetime, but last time I checked that is not the case anymore.  As with anything, economies of scale prevail not to mention the improved materials available now vs 20 or 30 yrs ago.

Now I have a question since this thread started debating leaded gasoline.  What good does the lead serve?  My understanding, as a young guy who never lived through the leaded generation, that the lead lightly coats the iside of the cylinder to make the valves seal better.  What would be the harm in not using leaded gas in our engines?  I had a '65 Ford Falcon that was built in the leaded generation that I never burned leaded gas in and it ran fine.  My cherokee had the STC to run unleaded mogas and best I remember there were no changes except paperwork.

Tetraethyl lead is the best octane booster ever found. Nothing works as good. It is very difficult to get gasoline to the octane numbers we need without it. All the other compounds that improve octane have bad side effects. The only bad side effects of lead is it is toxic and leaves a residue.

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IIRC (ya I'm a dinosaur) TEL (Tetra-ethyl-lead) was used originally to increase the octane rating of the gasoline so that higher compression engines (for more HP) could be made and run without "detonation" in the combustion cycle. Remember our training? Fuel "burns" in the combustion chamber, It doesn't "explode". Detonation is when it "explodes" violently causing holes in pistons.

It was also used  as a wear reducer on valve faces (a use or requirement now gone due to new metallurgy of valves (again IIRC, haven't taught this stuff for decades). 

Other chemicals and design parameters have been used to mostly negate the need for TEL now after the environmental issues were addressed to the release of TEL to the atmosphere (SMOG)

So some engines may not have the metallurgy to be able to eliminate TEL all together. And some (with our use of 130 year old technology on set timing from magnetos) with higher compressions and combustion chamber designs may also  not be able to use "regular" unleaded gasoline. Always bear in mind that our basic engine design for flat 4 or 6 cylinder engines is near 100 years old. Due to certification restrictions the design hasn't significantly changed since its inception.

As an aside, the cleaning up of the air has been beneficial. In the early 60s KVNY would have many days of "special VFR" , 1 mile vis due to SMOG. That is rare today. 

For those who weren't around then we had 4 grades of avgas rated by octane number-

80-87   was red

90-96   brown

100-130   green

115-145   purple

They were all dropped when 100LL (blue) came in. Again IIRC, 100LL has 1.5 grams of TEL/gallon and 100-130 had 4 grams (IIRC.  :-)

Edited by cliffy
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10 minutes ago, cliffy said:

IIRC (ya I'm a dinosaur) TEL (Tetra-ethyl-lead) was used originally to increase the octane rating of the gasoline so that higher compression engines (for more HP) could be made and run without "detonation" in the combustion cycle. Remember our training? Fuel "burns" in the combustion chamber, It doesn't "explode". Detonation is when it "explodes" violently causing holes in pistons.

It was also used  as a wear reducer on valve faces (a use or requirement now gone due to new metallurgy of valves (again IIRC, haven't taught this stuff for decades). 

Other chemicals and design parameters have been used to mostly negate the need for TEL now after the environmental issues were addressed to the release of TEL to the atmosphere (SMOG)

So some engines may not have the metallurgy to be able to eliminate TEL all together. And some (with our use of 130 year old technology on set timing from magnetos) with higher compressions and combustion chamber designs may also  not be able to use "regular" unleaded gasoline. Always bear in mind that our basic engine design for flat 4 or 6 cylinder engines is near 100 years old. Due to certification restrictions the design hasn't significantly changed since its inception.

As an aside, the cleaning up of the air has been beneficial. In the early 60s KVNY would have many days of "special VFR" , 1 mile vis due to SMOG. That is rare today. 

For those who weren't around then we had 4 grades of avgas rated by octane number-

80-87   was red

90-96   brown

100-130   green

115-145   purple

They were all dropped when 100LL (blue) came in. Again IIRC, 100LL has 1.5 grams of TEL/gallon and 100-130 had 4 grams (IIRC.  :-)

Many of the big, round supercharged engines used 115/145 purple avgas.  When it went away, the engines were limited in what the takeoff power setting was because they would detonate and buck like a horse at the previous takeoff power settings.

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They also used ADI injection (anti-detonation fluid, a combination of water, methanol and other chemicals ) to reduce the chance of detonation at max power settings. It also had the side benefit of cleaning all the carbon out of the combustion chambers when used.

You can emulate that benefit in your car by getting it up to temp and  pouring distilled water into the intake as it is run at a fairly high RPM. Keeping it running as you pour the water in slowly. This worked very well on carb'd engines after using the poor fuel down in Mexico and coming back with heavy pinging from pre-ignition due to hot spots with the heavy carbon buildup from the bad fuel. 

Early 707 jets with the straight turbojet engines (before bypass fan designs) used water injection on T/O to help keep the EGT cooler. They had a water bag in the wheel wells of about 600 gallons that used basically distilled water. We called them "water bombers". The Air Force early 707 tankers had the same engines and water system. 

Edited by cliffy
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2 hours ago, cliffy said:

IIRC (ya I'm a dinosaur) TEL (Tetra-ethyl-lead) was used originally to increase the octane rating of the gasoline so that higher compression engines (for more HP) could be made and run without "detonation" in the combustion cycle. Remember our training? Fuel "burns" in the combustion chamber, It doesn't "explode". Detonation is when it "explodes" violently causing holes in pistons.

 

Enron had a plant that made TEL.   It made a good profit for them.  Then we started to burn our food in car engines.

Wind turbines

Look up the total electrical consumption in the USA.   Look up total wind.   I have always wondered how many square miles are in the USA and is there enough land for the turbines.

Wind turbines work when there is tax credits and Warranty which is about 5 years.... then not so good

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2 hours ago, cliffy said:

IIRC (ya I'm a dinosaur) TEL (Tetra-ethyl-lead) was used originally to increase the octane rating of the gasoline so that higher compression engines (for more HP) could be made and run without "detonation" in the combustion cycle. Remember our training? Fuel "burns" in the combustion chamber, It doesn't "explode". Detonation is when it "explodes" violently causing holes in pistons.

It was also used  as a wear reducer on valve faces (a use or requirement now gone due to new metallurgy of valves (again IIRC, haven't taught this stuff for decades). 

Other chemicals and design parameters have been used to mostly negate the need for TEL now after the environmental issues were addressed to the release of TEL to the atmosphere (SMOG)

I presume by "smog" you're referring to the classic photochemical smog in the LA Basin in the 70's and 80's.  Photochemical smog is predominantly related to nitrogen oxide compounds reacting with hydrocarbons when exposed to UV radiation.  Since hydrocarbons are released with rich mixtures, and nitric oxide is released with lean mixtures (something to think about when you run LOP), there was plenty of both.  my understanding is the solution was a combination of catalytic convertors to eliminate nitrogen oxides, computer ignition to minimize the need for rich mixtures, and vapor recapture systems at the gas pumps.

Nothing specifically to do with lead, although it certainly becomes a particulate pollutant.

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3 hours ago, cliffy said:

For those who weren't around then we had 4 grades of avgas rated by octane number-

80-87   was red

90-96   brown

100-130   green

115-145   purple

They were all dropped when 100LL (blue) came in. Again IIRC, 100LL has 1.5 grams of TEL/gallon and 100-130 had 4 grams (IIRC.  :-)

When I was a line boy in southern Germany in the 70s our American flying club bought 115/145 from the US Army, for something like 0.25-0.35/gallon.   It was the prettiest purple and I always loved the color.   Spills were a total non-issue as the stuff would evaporate so fast you could watch it disappear in front of you.   I was bummed when we moved back to the states and the stuff in the sample cups was that ugly green.    The blue of the 100LL is still a far cry from that pleasant purple color.  ;)

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On 9/7/2018 at 6:34 AM, Mooneymite said:

Actually my post concerning electric planes was not motivated by any sort of environmental zealatry, but just from a performance standpoint.

Can you imagine electric flight where the ellectricity is beamed to the aircraft.  No batteries, no avgas, no internal combustion engine.  Just a smooth, lightweight servoed electric motor propelling a next-gen efficient Mooney!

Well... let me dream.  :rolleyes:

When I was younger I remember watching a show called “Beyond Tomorrow” or “Beyond 2000” which featured cutting edge technologies and experiments, and I remember a segment about this small UAV which was developed which used electrical power that was beamed via microwaves to it from a ground based antenna in order to provide it with the necessary electrical power to fly.  I imagine the plane couldn’t fly that far out from the power source but still the technology was mildly interesting at the time.

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Something about the distance from the antenna and the square of the radius or something like that that I learned many decades ago, determines the strength of the signal.. Way beyond my current memory. Just like going from one Boeing to another you do a brain flush of non-essential information. I "think" I could still start and fly a 727 though  :-)

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23 minutes ago, cliffy said:

 I "think" I could still start .... a 727 though  :-)

From which seat?

As I recall (and I don't recall well), on the 727, all three pilots had some part of the start.  FE set up the pneumatics and monitored certain engine instruments, FO held the start switch and the captain put the fuel to it....or was that another plane?  No one was supposed to be talking on his cell phone during start.  Oh, yeah.  We didn't have cell phones back then.  :ph34r:

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On 8/31/2018 at 2:07 PM, Jerry 5TJ said:

The original Swift 102UL was a binary mix of Trimethylbenzene and isopentane (maybe 70/30) a mix that produced 102 octane and had some excellent properties. It was not good in cool weather, and no amount of blending the percentages made it viable in cold weather, despite the superb octane. Even the Embry Riddle, FL folks could not get the engines to start in the frigid sub 50 degree F FL winter on Swift 102UL. 

Swift seems to be changing their formula ( percentage speculation: 20/70/10 trimethylbenzene, aviation alkylate, and isopentane) . In other words, it's 70% Avgas without the lead and their other two components. 

They claim this is to lower the cost, but I'd guess the real reason is cold weather operations. 

I had high hopes for Swift, I'm sorry to see them pull out. It ain't easy to get the lead out. 

 

I've been using unleaded fuels in very high boost race cars since the early 1980's, the trick was to use high percentages of toluene and to heat the fuel for proper atomization. 

 

MMT (methyl manganese tricarbonyl) is a classic octane booster that has been used for years, available in bottles at the local auto parts store. It's the stuff that leaves a reddish color on spark plugs and tailpipes. It's well understood and it may end up being the lead substitute in the next generation of Avgas. I question the safety benefit over leaded fuels.  https://en.wikipedia.org/wiki/Methylcyclopentadienyl_manganese_tricarbonyl    Interesting that MMT degrades in 2 minutes, when exposed to sunlight. 

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20 minutes ago, cujet said:

The original Swift 102UL was a binary mix of Trimethylbenzene and isopentane (maybe 70/30) a mix that produced 102 octane and had some excellent properties. It was not good in cool weather, and no amount of blending the percentages made it viable in cold weather, despite the superb octane. Even the Embry Riddle, FL folks could not get the engines to start in the frigid sub 50 degree F FL winter on Swift 102UL. 

Swift seems to be changing their formula ( percentage speculation: 20/70/10 trimethylbenzene, aviation alkylate, and isopentane) . In other words, it's 70% Avgas without the lead and their other two components. 

They claim this is to lower the cost, but I'd guess the real reason is cold weather operations. 

I had high hopes for Swift, I'm sorry to see them pull out. It ain't easy to get the lead out. 

 

I've been using unleaded fuels in very high boost race cars since the early 1980's, the trick was to use high percentages of toluene and to heat the fuel for proper atomization. 

 

MMT (methyl manganese tricarbonyl) is a classic octane booster that has been used for years, available in bottles at the local auto parts store. It's the stuff that leaves a reddish color on spark plugs and tailpipes. It's well understood and it may end up being the lead substitute in the next generation of Avgas. I question the safety benefit over leaded fuels.  https://en.wikipedia.org/wiki/Methylcyclopentadienyl_manganese_tricarbonyl    Interesting that MMT degrades in 2 minutes, when exposed to sunlight. 

I’m sure all the fuel companies are very familiar with these additives. There must be some reason why they won’t work. I wish the development was more transparent, but these companies are trying to develop something proprietary that they can make money with. I think this is the wrong way to go. They should just develop a standard that any patrolium company can meet. 

The problem is that almost everything that there is to know about fuel chemistry was known in the 1930s when the Cooperative for Fuels Reasearch Committee set out to develop auto and aviation fuel standards. They tried all the compounds they are trying now. It is like deja vu all over again. The one thing they didn’t have back then were environmental regulations. 

Unleaded car gas is a much poorer fuel than what was previously available but the car companies redesigned their engines to perform well with it. The same could be done with aircraft engines, but that’s not what they are after. They are after the holy grail that was ruled out 90 years ago.

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1 hour ago, N201MKTurbo said:

  

The problem is that almost everything that there is to know about fuel chemistry was known in the 1930s when the Cooperative for Fuels Reasearch Committee set out to develop auto and aviation fuel standards. They tried all the compounds they are trying now. It is like deja vu all over again.  

Mesitylene, the flavor of trimethylbenzene that Swift uses has been around for a long time, it was first produced in 1837! 

Some interesting reading. 

http://www.freepatentsonline.com/y2016/0168499.html

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There wasn't enough empirical data on this fuels stuff that we have to go out and reinvent the wheel?

I'm by no means a chemical engineer but unless someone has some "new" chemical to bring to the table it seems like all we a re doing is spinning our wheels/

How many pounds of  "stuff" are gas powered airplanes injecting into the atmosphere compared to what was injected 50 years ago by all contributors?   Again, is it now that so much has been removed over the decades that we a re now 100% of 2%?

Point of diminishing returns?

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It's interesting that even the mighty VP-Racing Fuels does not produce an unleaded with enough octane to match our lowly 100LL. 

Their best comparable product is C20, a non oxygenated unleaded with a MON of 99. (roughly comparable to the 100LL "lean" rating of 100) and a RON of 107, far lower than the "rich" 115 octane rating of 100LL. 

I don't want to say "it can't be done" but it's certainly looking like some form(s) or combination of octane boosters will be required. 

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3 hours ago, cujet said:

It's interesting that even the mighty VP-Racing Fuels does not produce an unleaded with enough octane to match our lowly 100LL. 

Their best comparable product is C20, a non oxygenated unleaded with a MON of 99. (roughly comparable to the 100LL "lean" rating of 100) and a RON of 107, far lower than the "rich" 115 octane rating of 100LL. 

I don't want to say "it can't be done" but it's certainly looking like some form(s) or combination of octane boosters will be required. 

How much is a gallon of C20?

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