The Long, Twisted And Slightly Ridiculous Story of Avgas Part 1
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- เผยแพร่เมื่อ 29 ธ.ค. 2024
- For decades, the general aviation industry has struggled with finding a replacement for leaded avgas without success. The biggest driver of this failure is that there's no reason to do so because the industry has been given an exemption to continue using lead.
In this two-part series, AVweb's Paul Bertorelli explains how industry inertia and bureaucratic foot dragging killed efforts to eliminate lead from aviation fuel. See Part 2 here. • The Long, Twisted and ...
For an excellent overview on leaded fuel in the wider world, see Veritasium's excellent video on the topic.
• The Man Who Accidental...
I must say, I’ve been really liking old man TH-cam lately. I like the no nonsense format and that these old guys aren’t necessarily in it for the high view count aka money rather just spreading informed solid wisdom and knowledge
Completely agree. The less waste of time, the better. Memes, antics, "infotainment", trashy B-roll, etc...complete waste of time. Content is king.
Very much agreed!
old guys? dude... He aint that old.
There are young "no nonsense" TH-camrs, too. I think wheat you're after is the "no nonsense" and I 100% agree.
Paul's also funnier than most, he has the bone-dry sardonic sense of humor down to a tee. he reminds me of aviation's Paul Harrell. i've known a couple old aerospace engineers that both Pauls remind me of. pretty much max level experience and expertise with a lot of wisdom and a very goofy and sarcastic sense of humor.
As a 5+ year user of Swift UL94 I was glad to see it featured. It is literally 100LL avgas without the lead and runs flawlessly. I go longer on oil changes, have no lead fouling and have never had an issue. I also run it in all of my power equipment. The 4+ year shelf life of the alkylate base stock makes it perfect for small engines and generators that only see occasional use. It is the answer to leaded avgas and needs to be sold more places!
Not so fast. Lycoming has not approved Swift UL94 for my engine type, plus a bunch of others. Yes, I agree, it is a great solution for some engines out there. But, until Lycoming gives the approval of such alternate fuels, I'm stuck with 100LL. And, yes, I know it "may or can work," but I don't want to face the repercussion of being a glider if things don't pan out.
@@paulbrunner1818 i dont want to get rid of 100LL. I just wish all airports carried ul94 for those of us who invested in the STC to run it.
Modifications to make an engine run on ul94 are a lot simpler that everybody is being lead to believe. Many just need an intercooler upgrade and in the worse case water injection.
@@ericfisher2053 "being lead to believe"
I see what you did there
@@ericfisher2053 you make that sound so easy. That's tens of thousands of dollars of modifications, and that's if some company already has an STC for your particular plane/engine combo.
Also, if Swift UL94 is just 100LL sans plomb, why does it cost MORE than 100LL? I understand that the distribution network is smaller, and if you're not buying direct, then you're subsidizing the airport's investment in carrying another fuel, but we're talking over a dollar a gallon, and it was closer to two dollars per gallon before the current petrol pricing madness. Considering there's literally one company in the world that still makes the tetra-ethyl lead for 100LL, I would think it would be much more economical to produce UL94.
I'm fine with having options, and when an unleaded fuel is available at a comparable price to 100LL, I'll bite. Until then, it's a no from me. I'll say $0.50/gal premium, and I'd really rather it be closer to $0.20. That's as much of a premium as I'm willing to pay. I get my blood lead levels checked routinely and the doc hasn't noted anything alarming, and most of the lead I'm exposed to probably comes from my other hobby of reloading and competitive shooting.
I have been flying for 48 years. I have almost 26,000 hours. And this guy blows me away. I learn when I listen to him.
I have the unfortunate circumstance of owning two airplanes, one of which requires 100LL, the other of which has an STC for unleaded auto fuel. At every annual, the LL airplane spark plugs have to be cleaned - the usual vibratory tickle followed by an air blast/abrasive cleaner. And it really takes some elbow grease, I might add. Last year it didn't even make it to annual, despite the supposedly superior fine-wire plugs and newly-serviced mags.
The second aircraft has not required cleaning the plugs a single time since I got the STC for unleaded auto gas - about ten years ago. And yes, I DO lean both aircraft for taxi - severely.
Put me in the "get rid of LL" column.
LL is stupid as fuck and no engines need it anymore. Unless you're flying a 1920's plane haha
I wish I had half of your unfortunate circumstance.
@@9HighFlyer9 One thing you learn to never do is calculate your real cost per hour of flight. If you add in your work to the calculations, generally people go straight to the nearest loony bin and turn themselves in. My wife said that either the airplanes went or she went. That was my first wife. (and second).
@@jwills8606 Your a very smart man. Those airplanes don't talk back do they?
@@jwills8606 Same for me with the motorcycle ultimatum. Bye!
"If you were smart about money, you wouldn't own an airplane". As an aircraft owner, I can confirm this statement lol. Try between $7 and $8 a gallon where I live
Here in Australia avgas is $2.80 to $3.00 a litre there is 4.6 litres to the US gallon
@@spannaspinna That’s more the Imperial gallon. Old enough to have purchased gasoline by that unit in Canada. U.S. gallon is closely equivalent to 3.8 liters.
Multiply price of fuel per gallon. Multiply gallons per hour fuel burn. Multiply hourly fuel cost by hours flown annually. Then multiply the total by 5x for an estimate on aircraft ownership.
Cessna 172. 10gal/hr x $6 = 60. 60 x 5 = $300/hr. (Yes. Including annual inspection, all maintenance and repairs, tires, hangar, insurance, and depreciation, or restoration to maintain value).
$300hr x 50hr per year is $15,000 annual cost of ownership for Cessna 172. (Now, add monthly payment amount x 12. Correct, this is not included and goes up with the value or newness).
I'm not going to lie. The Dallas Cowboys line stung a little.
Well you can take comfort in them having a far better chance than the Det Lions!
The truth hurts😅😅 I've been riding that Cowboys rollercoaster my whole life
The Make it political guy is here. We can all go home. Shut it down. #Gross
@@JustPlaneSilly Everything's political now dude. Let's go Brandon! MAGA now more than ever!
@@JustPlaneSilly do you ever fly to west Texas? I know there is zero scenery here but have wondered if you're ever in my neck of the woods
It is a crime this video doesn't have like a billion views from day one. Perfect execution on the topic. Its so baffling to see how lack of regulation and need of- improvement stagnates some markets and technology, specially one as beautiful as GA
Man I think you are by far the funniest and most knowledgeable aviation TH-camr around, seriously.
Detonation is only half the story. Vintage Cars use modern valve seats and guides to get by the lubrication that lead also provided. It’s time to leave the 1930’s behind.
Can we keep the wheel?
@@Milkmans_Son Luckily that was invented slightly longer ago than the 20th century.
Lead's main job is to increase octane to prevent detonation which is destructive to engines, but it also protects the valve seats by providing a thin sacrificial metallic layer between the valve and the seat to prevent high temperature microwelding that erodes soft seats. Higher octane fuel lowers combustion temps and that helps preserve soft seats too, but not completely, so hardened valve seats fixes that issue. But contrary to popular belief lead actually adds no lubrication value. ok? So high compression engines that don't already have hardened valve seats will most likely eventually need them to be installed to be able to use a high octane unleaded fuel that then will only need to prevent detonation. That is the key here I believe.
I remember the uproar that the elimination of leaded gas was all a giant conspiracy by the government to harm auto engines and that lead was perfectly safe. I'm glad to see you reinforce the reality that lead is an actual neurotoxin that should have been removed from gasoline.
Do people actually argue that it's not harmful? I've never run into that before. Despite, almost entirely for amusement, hanging out in flat earther, chemtrail and other conspiracy corners of the internet.
@@9HighFlyer9 yes. Older engines didnt not have hardened valve seats. Lead cushions them. If you ran unleaded in such an engine you would destroy the valve seats. Which is also one of the reasons avgas still has lead.
@@9HighFlyer9 I don't hear that argument much any more. This was back in the 90s. As pointed out by Demonslayer below, the concern over engine wear was legitimate albeit minimal given the already growing number of unleaded vehicles at the time. The *conspiracy theory* was that it was done intentionally to cause wear and thereby make everyone buy new vehicles blah blah blah. My dad asserted this in no uncertain terms (which is why I remember it so well) and, I'd not be surprised if he still rolls out this narrative today. He also asserted that there was no safety issues with lead in gas as it was all a liberal hoax in service to the conspiracy theory.
@@Demonslayer20111 old polluting engines deserve to be broken
@@DaveHojo lack of knowledge and science understanding
This guy can give u a lecture on quantum mechanics and how to make paella at the same time in less than ten minutes and u will understand everything he says, remember everything , just a marvelous educator, best I have seen in my 60 years of painful boring education
This would be a non-issue if the FAA had given engine makers a 5 year period after the autogas lead removal to develop engines that didn’t require high octane fuel. If the FAA had banned production of engines that required more than 91 octane starting in 1990, we wouldn’t be having this conversation today because by now pretty much all of the legacy engines that required 100LL would have reached their end of life and could have been replaced by the new engine designers without undue hardship to the owners. Then once the engines were nearly all purged naturally from the fleet, banning the use of 100LL in 2020 would have been nearly a non-issue.
I have always said this. Once these ancient peices of junk are allowed to not only be used but be in continual production, there will be no incentive to change.
@@TRPGpilot I agree. I think current engines should be grandfathered in until they reach their end of life to prevent economic harm to current owners, but I think the production of new engines needing 100LL should have been stopped decades ago.
the faa said it was coming in 2002, you've had 18 years.
@@jmwintenn The FAA said what was coming? And nobody believes or trusts the FAA anyway. Just look at NextGen…
It would be even simpler if the switch was made to turbo diesels. Then small planes could fill up with kerosene just like jets. There was even a diesel Cessna for a few years called the Redhawk.
This is fascinating and well done. Thanks for the very informative and high quality content. Can't wait for part 2!
th-cam.com/video/Mvse4Xhzwuk/w-d-xo.html
UND has already made the switch in our Archers and Seminoles to UL94. I’m looking forward to using it this coming semester.
Electric trainers are the ultimate future
@@Nicholas-f5 The downside of that is it doesn't teach new pilots engine or prop management. Electric plane doesn't require messing with mixture or messing with a constant speed prop, it basically reduces engine management to watching battery percentage and temperature and making sure you don't over torque the shaft
1) Good to see you covering this Paul. Was maddening listening to the Air venture forum regarding fuel.
2) Also: "Innospec Ltd" in the UK is the only place that still makes tetraethyl lead. What happens if . . .
3) Will be great to not deal with stuck valves and fouled plugs one day.
That filled in some gaps for me. Thanks, Paul - I'm off to see Part 2...
MOGAS being only slightly less expensive than 100LL seems like a non-starter until it's time to cough up 5 figures to get your engine overhauled and you realize the primary reason was because of lead coating the inside of the engine.
HA!
Mogas essentially pays for overhauls
You are a knowledgeable, funny, and entertaining guy Paul, keep up the good work. Great summary on where we were and where we are now WRT tetra ethyl lead.
Another excellent video by Paul! To think we were cluelessly sniffing this stuff in fuel testers and breathing its exhaust for all these years.
Great info and presentation as always, Paul. Thank you. Ready to watch Part II.
th-cam.com/video/Mvse4Xhzwuk/w-d-xo.html
Thomas Midgley eventually was strangled in a device of his own manufacture , he had designed it to give himself some mobility after contracting polio.
I always figured the lead was so low maybe it didn't matter and was below some regulatory standard threshold. Makes me really rethink all the times fuel spilled on my hand while sumping and I just shook it off, I did figure the propeller and slipstream kept the exaust particles away or at least very diffuse. Should probably have been wearing gloves at least. Sad that we can't eliminate the use of something known to be so toxic in an industry that is not only tiny but has solutions available now. The disregard for the environment and people in it is just...I don't even know.
I’m a 20 year old line service tech, and I breathe this stuff in every time I fuel an airplane. Probably slowly killing myself at this point
Even worse, the inventor himself knew it was bad, and still pushed it out of the lab into the world. He knew it.
@@flibbettyjibbetts6766 damn. Hope you're well. The shift to mogas seems to be well underway.
Small, reliable turboprop motors is the answer. Cheaper Jet fuel, double TBO. Why doesn't P&W make a small version of the PT6?
Cost
HUGELY more expensive up front. Turboprops are reliable as is, but it doesn't make them economical.
I don't even like to fly... but never miss an episode that features Paul. He never seems to smile/laugh but makes me pee down my leg!
Best summary ever!! FAA presentation and AOPA discussion on this topic at Oshkosh was pathetic!!
Hell yeah more Paul content
I'm surprised aviation diesels haven't caught on more (I know Diamond uses them extensively but they're about it), that seems to be the real solution. A piston engine that runs on Jet A and is easy to manage because mixture control is automatic.
Yep. All you need is a skyhook to handle the weight.
Great presentation. Paul Bertorelli could be discussing rutabaga crop rotation in Honduras and I would find it interesting.
exactly, i love him
Darn, now I wanna hear Paul talk about rutabagas and the Honduras...
I just found this channel, and as a glider towpilot I will be referring my glider pilots to it to try and help them understand what we go through, as at most glider clubs we consider MOGAS a not acceptable option. I'am subscribed!
Now that several people report about all airplane crashes here on TH-cam, a common thread is that the failure occurs after some type of airplane or engine maintenance. It makes me wonder if all the required inspections really reduce the incidents. Your analogy about low car engine failures vs high airplane engine failures is a good one and one I have included in other comments myself.
Considering how toxic lead is, its a bit shameful to still have leaded gas.
Lobbyists like AOPA don't care
@@Nicholas-f5 All that lead emitted by those relatively few small planes with small engines pales in comparison to all the lead that's still on steel skeletons of older high-rise buildings and bridges (as anti-corrosion paint), old church roofs (watch that white plume of pure lead (II) oxide rising above burning Notre Dame cathedral in Paris), or the lead that hunters and "target/ bottle shooters" pump every year into the environment... Heck, forget it - think of all those lead acid car batteries that don't get recycled - granted, "nearly 100%" of them DO GET recycled, but that 1 or 2% that does not...
_in October 2020, ..., the EPA posted the statement that "In 2018, the estimated amount of recycled battery lead was about 99 percent ..."_
... which sounds kinda great, until you realise that the TOTAL amount of those batteries produced was in the order of...
_ The Battery Council figures indicate that around 15.5 billion pounds of battery lead was consumed in the USA in [2014-2018] period, with a net amount of approximately 2 billion pounds battery scrap lead being exported. Of the 13.6 billion pounds remaining after exports, 13.5 billion pounds were recycled ..._
...and that leaves us with 0.1 billion pounds, or 50,000 short tonnes (US, approx 45.4 metric tonnes or 45,359 kg) of lead "unaccounted for" - in USA ALONE, in four years period ONLY. Makes you think, eh?
(Quotes from Wikipedia - en.wikipedia.org/wiki/Battery_recycling#Lead.E2.80.93acid_batteries.)
In other words, "you're barking under wrong tree, my dear Watson..."
;-)
Paul,
Great video and subject and Im a non-pilot - thank you!
Paul (in MA)
I believe sir that Sir Harry Ricardo should have received a mention in Part 1 for his work in 1918/19 on engine 'knocking,' that led to the development of an octane rating system for fuels.
Ethyl Chloride gave the fuel that pretty perfume smell, also evaporates rather quickly over 52F so when you opened the gas cap it make a hiss til the top vented off.. Thomas Midgley Jr. was from Beaver Falls.. This where Im from a bits. He was an American mechanical and chemical engineer. He played a major role in developing leaded gasoline (tetraethyllead) and some of the first chlorofluorocarbons (CFCs).. Thomas Midgley Jr was known as a "one-man environmental disaster...
The Citation Needed episode covering Thomas Midgley was terrifyingly hilarious.
Glad to see the explanation... A very complex background on Avgas...
Thanks for the info. I'm just starting to pursue my pilot's license, so I like to look at various websites and see which planes are available, and daydream. I had been wondering why some of them say they can run on car gas and others say Avgas. This video gave me my answer.👍
I have a PhD in Law and Public Policy. My focus is on climate/energy policy which means I have complex feelings about flying for fun. I've dreamed of the day when I'm rich enough to just put a diesel into something and run on biojet instead of 100LL. But mostly I came here to say: Your point about policy protecting the use of Lead and inhibiting the search for alternatives is dead-on, and I'm thrilled to see a discussion of the fuel space include that. Alas, I have but one Like & Subscribe to give...
I'd be interested in hearing your thoughts on climate and energy policy as in my experience those pushing "green" policy have not even a primary school understanding of the subjects outside UN corporate narratives. Saying things like "put a diesel into something" leaves the door wide open as to your understanding of complex systems. The addition of a liquid cooling system in diesel fit outs is an increased weight and decrease in safety. And just because a fuel has "Bio" in the name does not mean its environmental impact is friendly or sustainable. They certainly aren't profitable or the world would've gone away from oil a long time ago.
Something not mentioned in this presentation was the lubricating properties of lead in fuel which has a significant influence on design tolerance and material choice for components like valves, valve guides and valve seats. Engines with overheated exhaust valve components run out of compression quite quickly. Engines without compression lose power. Aeroplanes without power fall out of the sky.
Now if you work within the field you claim to you should be well aware, unless ignorant beyond any acceptable metric, that the lead in the atmosphere from small aircraft and carbon dioxide from transport is well down the list of atmospheric pollutants and basically insignificant compared to chemicals released by governments.
@@jdoe9518 You're correct that diesel comes with tradeoffs, but that's true of literally ANY alternate scheme. You're also correct that "Bio" doesn't mean environmentally friendly, per se. That said, closing the carbon loop and not using lead are attractive qualities to me, and just because something isn't the #1 offender (is "well down the list" as you say), it doesn't necessarily follow that it's therefore pointless to address anyway. A thing need not be as bad as possible before we decide we want to do something about it.
@@cavalierqoon carbon dioxide... 0.4% of the atmosphere. One of three essential components for ALL plant life on this CARBON based earth. You are aware of what photosynthesis is? And that it produces OXYGEN as byproduct?
So currently people such as yourself are reducing carbon emissions and nitrogen (78% of the atmosphere) fertiliser production. Now I'm no PhD but it appears your policies are trying to significantly reduce plant based food production and the ability to create "bio" fuels.
@@jdoe9518 Your concerns would be warranted if 1) Carbon was a limiting reagent for life - it is not (water is, in most places), and/or 2) the world was suffering from land shortages for agriculture - again, it is not (the appearance of shortage created by deforestation, etc. is due to poor planning and market failures rather than an actual meaningful shortage).
Moreover, biofuels are most efficiently produced using things like sewage, which I strongly caution you AGAINST using as a source of food. You do you, though.
@@cavalierqoon To be clear you don't believe carbon is a reagent for life? On this carbon based earth with plants that require carbon dioxide for photosynthesis?
Good news! If tractors, farm equipment and trucks run on sewage so can the aircraft you'll never own. Unaware of sewage fuelled power stations but I'll keep an eye out for them.
The world is better place with people like you being involved in policy making.
If you could stop breathing out carbon dioxide you'd being the world a solid😉
UL94 has been great for my old Franklin 165 with its 7:1 compression. No more fouled plugs. 😊
Don't know how I got here but stayed and learned something. Very interesting. Thanks for sharing.
2:43 im just a lowly diesel tech but is octane the resistance to predetonation? which at the impossibly high speeds of an engine would appear as a smoother flamefront under the continuously increasing compression in a cylinder. being a pedant here
Well presented, as always.
In latter WW-II they were making 150 octane airplane fuel. The refinery for it was in Gaylord, MI to keep it hush-hush and far from potential enemy attack.
One thing you forgot to mention. Hardened valve seats. Older engines did not have hardened seats as the lead did another job on top of boosting the octane: cushioning those seats. If you ran unleaded gas in an engine with unhardened valve seats it significantly reduced the engines service life by destroying those seats
Something we learned about in the AMT program i went through to get my A&P license.
Smash the engines and melt them down. Problem solved.
Nicely done so far. One execption - ethanol. It does not go through pipelines it is all ground shipped. This means it is added at the terminals, not at or in the manufacture of gasoline. It can simply be not added for the trucks going to the "gas stations". There is also a clear gooey additive for lubricity added at the same time.
Really wonderful job explaining complex topics.
Back in the 1960s, the three grades of auto gas were Regular, Ethyl and Premium . . .even though TEL was in all grades. One of the many things that I love about my Cessna 150 is that it runs on autogas (and with such low fuel consumption, it's convenient to buy at gas stations and cart to the plane). One of the advantages of using autogas is the lack of lead fouling on spark plugs. Good old 80/87 avgas had about 30% as much lead as 100LL ("LowLead").
Mogas essentially pays for overhauls
These ancient lycoming and continental boat anchors are just ridiculous - they make stuff from the 1960's look modern. The amount of work they extract from a gallon of gas is simply shameful. The industry needs to get over itself and embrace unleaded fuel, liquid cooling, and electronic controls.
US lawyers will prevent that from happening. The Lycosaurs deliberately don't see any development, because any failure of a new design will be used by lawyers to extract gazilions in compensations.
@@erik_dk842 that's it in the proverbial nutshell... attorneys...
What is your thought on the FAA approval of GAMI 100 unleaded?
I been looking for some one to help me learn about different fuels honestly your the best with explaining it !
Can’t get enough of these videos. *High-5* Paul!
Glad to find your channel. My boss swears that leaded fuel was better and uses AV gas in his mowers because of this. I try not to use ethanol gas too much but it is in all the gas.
Excellent presentation and content!!
Back in the 20's they found that triaryl bismuth also worked, though its concentration needed to be four times higher than tetraethyl lead for the same increase in octane rating. At worst it would fill the environment with Pepto-Bismol. It would be interesting if one of the fuel companies would do some more testing with it, especially at the higher octane ratings that would WW-II era engines perform as designed.
Would help people with heartburn
So well written. Thank you!
As a flying enthusiast (as a passenger, not a pilot), I had often wondered about the qualities of Avgas compared with car fuels, and I found your presentation absolutely fascinating, especially the problems with ethanol in the car fuel.
You made a mention of Charles Kettering as the inventor of the starter motor. He did file a patent in the USA in 1911, but the first US patent was by Clyde J. Coleman in 1903. The first actual installation of an electric starter was even earlier, by H. J. Dowsing in 1896 in a Benz Velo.
As far as I am aware, the first US car to have an optional electric starter was the 1913 Partin-Palmer (no relation, as far as I am aware) but I have no idea when they became standard on aircraft.
I'm now going to watch Part 2.
I believe that Kettering also invented the first military drone, the Kettering Bug, used in WWI.
They need to ban production of new engines that require 100LL or new technology won’t be cost effective to pursue. Lycoming and Continental both already have Diesel engines that they could start using on more new aircraft. Forcing new aircraft to use them will increase demand and lower the price due to economy of scale.
Excellent, thorough, clear, and concise presentation.
Great work!. I missed the part why Rotax are made for mogas ( better cooling system, coolant based like cars)
The Euro diesels (turbos) use Jet A. Not available in parts of the US GA ecosystem. They seem to have fuel economy and no lead. Is this part of the solution? Just like the no lead option, is it just an availability issue? Is it a matter of building out our existing GA facilities for better fuel options?
In Europe lots of smaller aircraft are retrofitted from AV-gas into TurboDiesel engines.
f.e. the Continental CD-135 has been certified for it and uses regular automotive Dieselfuel.
I heard that in the U.S. certification on statelevel and availibilty of dieselfuels for aircraft is dragging / low.
Has this to do with the historicly grown reluctance to dieselengines ( GM's Diesel V8 debacle ) or are there other things in play?
Ethanol was not added to auto fuel because of the ethanol lobby, but as a oxygenate replacement for MTBE which is nastier than lead. Like the transition to unleaded fuel, ethanol is a viable solution if you deal with it correctly. It does not create water, but is hygroscopic, if dont have the water you dont have absorbtion and like gasoline once it is saturated it will sink to the bottom and can be drained, prior to that it will be burned in the combustion chamber sort of the like water injection system you said was a good idea.
" if dont have the water you dont have absorbtion"
You realize that air itself contains water, right? And the amount of water air contains varies greatly. Ethanol, and other alcohols, will suck water right out of the air. So, to keep ethanol from absorbing water you'd have to ensure it never came in contact with air.
@@stefanl5183 Of course, but even in the most humid climates the actual mass of water compared to the mass of fuel is miniscule. People do tests by dumping in massive amounts and showing what happens. If this is what is going on inside your fuel tank you have much bigger problems.
Say 90 F, 50% humidty which is Lousianna is the summer it is 0.01 lbs of water per poud of air. Air's denisty is is about 0.08lbs/cubic foot, so to get 1 lb of air would take about 125 cubic feet, which in a very humid hot atmosphere would have 0.01 lbs of water which would be 0.0012 gallons of water. Look at the average fuel system and you can see how blown out of proportion all this is.
Um.....I have never seen any research report that suggested MTBE was more dangerous than lead. Unsafe? Sure. But lead is extraordinarily dangerous, especially to children.
@@paulmaxwell8851 There is no doubt that lead is nasty for humans and was replaced mostly by MTBE as an oxygenate and oxtane enhancer. While MTBE can be toxic to humans not nearly as much as lead, the issue is that MTBE is very toxic to the enviroment, especially drinking water where a small amount can render large quantities of water non drinkable. Ethanol was introduce by law as a substtitute and we can argue forever about it's pro's/con's and whether it is a lower cost alternative, etc. Reality is it is here to stay and the oil companies dont like it, as it impacts their supply process and they dont make it and have spent literally billions on marketing quite successfully convincing the public that it is the enemy. The aftermarket has also reaped an enormous windfall in selling snake oil solutions that in reality dont really exist, not to mention the mechanical repair businessess who blame everything soup to nuts on it.
@@stefanl5183 we call that moisture
When I was a kid in the early 1970's, I could taste the lead in the air. Cities stank of unburned fuel. I had terrible asthma as a kid. Cleaning up the air ended my asthma.
Jesus, that's like Mexico today
We're headed back to those bad old days thanks to the current SCOTUS. Get your inhaler ready!
Great video as usual!
I knew the story of lead in fuel but almost nothing about the story of av gas!
I also was amazed by the fact that there is fuel with so low octane grade availiable in US !
MON numbers are lower than RON for the same grade fuel
@@yamezzcuross4353 thanks!
So to what grade is a 87 octane fuel equal to?
@@mitsos_306 I think 91
@@yamezzcuross4353
it is still low.
I live in Europe and the lowest grade you can find is 95. I use 100 octane "shell racing" to my car, but most people use 98.
This changed though the last year since fuel prices skyrocketed and now the 95 is the most popular!
@@mitsos_306, Shell 100 [RON] in Europe is 88 MON and 94 AKI (used for road gasoline in US+Canada). AvGas is 99.5 min MON, big difference.
My "beef" w/ GA is the lack of muffler use. I've been flying since '77, when I received my private pilot's license, and questioned my instructor/father as to why no aiplane had a muffler - I can't recall his exact answer but it was something to the effect that planes were high up enough to negate such a need. I disagreed and when we bought our first airplane together, I secretly installed a muffler (glasspack) on our new-to-us Bonanza. Next time we went to fly he saw my addition and we had a heated discussion as to the muffler's aerodynamic drag, yada, yada. He finally fired it up and immediately I could tell, he liked the lower decibels. Most other pilots laugh or shake their heads when they see my mufflered Bonanza, but I love that glasspack, recently updated to an under-cowl version, after completely re-working the exhaust system. I'm a motorcycle fan, as well, and my fellow riders all chide me about riding a "rice burner," cause I ride an older Honda VTX, cause its smooth, fast and, most importantly, quiet. That I can out-corner them all really chaps their asses. hehe
Mufflers lower power output slightly. Unnecessary part to have on a plane that will just need to get fixed in the future. Never would want to fly a Cessna 150 with a muffler.
I hope you got an STC for that modification.
@@Demonslayer20111 Never bothered.
@@v.e.7236 Pay off the ia doing your annuals?
@@Demonslayer20111 It's been over twenty years since I owned and flew that plane. I'm no longer flight certified due to a spinal chord injury and age.
Thanks for a great presentation!
Excellent lecture of going over the history, why AVgas is the way it is, calling out various suspects (the corn lobby), and to do it all in 15 minutes. You mention GA, do airliners use leaded gas? Doing a search, I only get piston engine fuels. In my area the decades long effort to close Reid Hillview airport (one of the last airports in a city for single engine piston airplanes) the issue of leaded gas is the latest to effort to close the airport. There are other airports for GA but those are for the top 1% and their "lear jets."
Great video… Thanks… Very informative… I’ll have to watch it a few times to take it all in!
9:37 I fly near that ethanol facility in the picture! Fun fact, the brown silo in the back is that color because the corn inside is actively on fire and it smells awful.
Great video though, and very eye opening.
so that WAS Fulton NY. I work literally down Rt 57 from it and have caught whiffs passing by. Its been burning since when, Spring?
From long ago memory I recall a discussion from a forgotton source that Standard Oil supplied TEL to Germany as their engines would blow themselves to bits without it too.
6:45 Why did avgas production drop so much? Higher engine efficiency?
He said it. Jets.
Excellent info as always thank you
Does anyone know if you can just add "tetraethyl lead" into normal gasoline and it be the same as leaded gas?
I have alot of physical lead and the chemistry process of making it with lead and sodium looks pretty easy and straightforward.
I adore flying and got started with PPL training last year. Every time I would sump the blue stuff I'd get a huge feeling of guilt and regret, and I decided I just couldn't stomach willingly burning the stuff. The dumbest thing about this isn't the FAA's recalcitrance in approved an unleaded fuel...though that's terribly dumb...but the fact that non-ethanol mogas isn't available at just about any GA airport, despite dozens and dozens of engines being able to use it. 100LL a necessary evil would be one thing, but its use fouling engines that don't even need it is incredibly dumb.
Dont worry, electric planes will be falling from the sky real soon.....🤣
@@will7its I wish we could have hybrids with electric taxi, takeoff, climb, descent, and landing, with Rotax-powered cross-country cruise.
@@zachshaner I wish I could have a couple supermodels too.....lol
“Detonation isn’t much of a thing in mainstream cars anymore” what do you mean? These days I can get a an sx model of a common sedan which comes with a slightly beefier eco-boost, and the owner’s manual recommends regular gas, but I get a sudden power drop at high load when I use regular gas like it recommends. Using higher octane resolved the issue. So it’s still a problem sometimes, it depends on the circumstances and the kind of car you drive. Yes, a Kia Forte is a “mainstream car” for what it’s worth, even if some of the lineup in the family comes with fun little features like a turbocharger, short-geared manual transmission, and a slightly higher-compression engine.
Great backdrop and setup for part 2!
5:03 maybe accounts for ? Situation?
Thanks in advance
Two months ago, I was at Thermal airport (KTRM) and saw Jet-A at $9.50/gal. …Thank goodness I had a company credit card.
That's what the FBO is hoping too 😂
@@Nicholas-f5 😜😎🤩
The airlines must get a different price. An airliner burns several TONS per hour. Unless they get it cheaper I don't see how they exist.
2:37 that’s more likely caused by a valve failure, but we get the point. Detonation typically eat at the top ring lands, pounds the connecting rod bearings and kills the ring tension, all bad stuff!
That looked like melt damage from detonation more than it looked like mechanical damage from a dropped valve.
@@carlwessels2671 not to me.. I would bet it being a dropped valve that wan for a while and polished the pistons while beating a hole in it.. I’ve seen it.
@@carlwessels2671 Detonation eats the edges of the piston. Pre ignition melts the center. But there is definitely foreign object damage there too.
For sure not detonation.
@@billshiff2060 A bit of pre ignition and foreign object damage. Definitely going to be work to fix that engine.
In 1973 while living at a rural airport I realized my ‘64 Porsche SC with 9.5 compression was out of gas and the nearest gas station was five miles away. So I pulled up to the gas pump and put $5 of $1/gallon 100 octane in. Car sure did love that stuff. Wished I could afford to fill my tank with $16.50 worth of gas instead of $5.50 in street gasoline.
I love Paul and his aviation takes!!
Just an excellent take on our systems/ fuels. TY!
"If you're smart about money you wouldn't own an Airplane"
🤔 yep that's true. Lol.
As I'm saving to buy a plane.
If it floats flys or fuçks rent it!
@@thetoecutter13 can it do all three?
@@Nicholas-f5 If she's really talented she might be able to.
Higher octane fuel doesn't have more power, but does that apply regardless of octane? I understand that regular and premium gas both have the same power but premium can withstand higher compression before detonation. What I'm curious about is, does the old gas that was in the 60's as far as octane rating, still have the same power as our modern fuels?
One point not covered is the lead acting as an exhaust valve and seat lubricant. Anyone with an older auto or motorcycle knows what happens to your engine without the lead. Very quickly you will be replacing the valve and seats. This applies to most any engine built before the lead fuel ban. What percentage of GA aircraft is older than 1975? Rebuilds for all will be required.
I live in alaska so there is no ethanol fuel here, my 59 c182 requires only 80 octane, so I take my truck with my 100 gallon fuel tank to Costco every once and a while to get auto gas and it’s way cheaper. One thing I have noticed though is that there is a lot more gasket material in the sumps with auto gas.
Wow, really well done! I just subscribed.
Great Video.I build home plants for gasoline small production.This is a very important aspect in gasoline production. Big 👍from me!
One interesting historical fact is that Germany solved this problem during WW2 because they couldn't produce 100 octane gas initially and it was a serious disadvantage. Germany instead developed (copied from a British researcher actually) the technology of water/methanol injection. A 50/50 mix of water and methanol sprayed in with your fuel effectively allowed you to operate as if your gasoline had 100 octane even though it only had 87 to 89. Germany did eventually develop C3 fuel which really did have 100 octane, but they continued to use water methanol injection because they were not able to make enough C3 fuel to meet their needs (plus it was synthetic garbage and had a lot of problems). Both the BF109-K4 and the FW190-D used water/methanol injection to inhibit knock and make more power on B4 fuel (87 octane) and they matched the power of other BF109's and FW190's using the 100 octane C3 fuel. Of course american planes by that time were on 130 or even 150 octane, so it wasnt a perfect solution. However we are only talking here about 100 octane which is easily reachable using water/methanol injection. In fact it is even EASIER to reach 100 octane today because you can start with 94 octane unleaded and non ethanol mogas instead of starting with the german 87 to 89 octane B4 fuel from WW2.
Fun additional fact. ADDING water methanol injection to an existing engine was relatively easy, and that is exactly what the germans did for the BF109. They could refit old engines in the field by drilling out the intake manifold and adding a spray bar for the water/methanol injection. This means existing planes that require 100 octane could be refitted to use 91 to 94 octane gas with water/methanol injection without replacing the engine.
I know the F4U corsairs water injection system was mentioned, but water/methanol injection is significantly better at inhibiting knock than a pure water injection system.
@@jajsamurai the Navy doesn't like methanol - it burns with no visible (to the naked eye anyway) flame
@@FaustoTheBoozehound if you dont like methanol just use pure water. we are only talking about taking premium 93 octane gas to 100 octane. the germans went from 87 octane to 100 octane using 50/50 water methanol. water by itself is less effective, but we can start with much higher octane, so thats fine.
the point is the solution is there if anyone wants to use it. No one wants to put in any effort because we keep extending the exemption to just maintain the status quo.
Gotta take issue here. At 2:10 you correctly state that pre ignition is NOT detonation but then at 2:37 show a photo of piston damage you say was caused by detonation. However that piston does not show the normal detonation damage at the edge of the piston and ring lands. It does show the signature damage of pre ignition with a hole melted in the piston center plus some damage from a foreign object rattling around in the chamber of a still running engine. It contributes to the general misunderstanding of the 2 issues out there.
Lemme chime in and drop my twopence here... While I don't know a sh... erm, a thing about "how a damaged piston should look like" I'd like to clarify that "detonation" thing - the difference is in speed - thus it is about "power (pressure) delivery ratio".
"Normal" internal combustion is what technically is referred to as deflagration - burning that propagates at few metres per sec, maybe a hundred or two at most (as might be in the case of a gunpowder being burnt inside bullet casing or a shell).
And the detonation is something that propagates through shock waves, at supersonic speeds, often reaching few KILOmetres per sec.
That makes the "energy delivery" substantially different - it's like pushing doors, hard, with your hand versus delivering a swift blow with a dead-blow ten pounder "persuader".
In both cases you'll get the door open (eventually), it's just that the door itself... well, you get the idea, don't ya?
Also, I think that in some cases it could be "just" a multi-point quick deflagration (i.e. flame "front" does not start at spark plug ONLY and then propagates, as a single front, through the air-fuel mixture, but instead the mixture pre-ignites, because of too high a compression ratio, at many spots simultaneously, which might not produce the "proper detonation" but it'll have a similar effect - too much power released at once.
But then again I might be just wrong, who knows...
@@MrKotBonifacy Pretty much correct to my knowledge except that the shock wave propagation happens after the detonation reaction itself and proceeds from the reaction location. That location is almost always at the edge far from the spark site. The heat, shock wave, pressure is highest there. It scrubs away the insulating boundary layer and directly heats the surfaces there, eating it away.
What you are describing is a milder form of pre ignition known as "rumble". It occurs late in the cycle near the normal spark timing so is not as damaging but does cause noise and resonant vibrations that can cause damage.
Early pre ignition results in the piston compressing the full fireball of combustion which results in a giant heat input into the piston , concentrated in the center because the main heat of the combustion is highest there and the center is the farthest from the cooling walls. Within a very few cycles the center softens and blows a hole through the dome.
In the photo shown , something kept the piston operating long after the hole appeared(the other cylinders no doubt) and debris beat the top into a moonscape.
The edges of the piston show no signs of being blasted.
@@billshiff2060 Thanks for detailed explanation - you can always learn something new when you listen to people who know stuff...
: )
I do not own an aircraft and "probably" never will (unless someone will give me one for Christmas, but then I do not really expect it to happen any time soon... OK, just make it "any time") - still, it's nice to know a little bit more about "how stuff works"
About that "the shock wave propagation happens after the detonation reaction itself and proceeds from the reaction location" part - yes, "precisamente, amigo" - the detonation propagates by a shockwave from the initial point of detonation - I sorta cut corners here, since my point was to point the differences between those two "propagation modes" (heat transfer vs shockwave) and the speed of those propagations.
Cheers, and have a nice one ;-)
@@MrKotBonifacy YW the point I was making is that the heating mainly occurs where the detonation starts.
Also pre ignition and detonation can cause each other and exist at the same time, separately or sequentially since they both cause more heat into the chamber.
@@billshiff2060 Agree. No difference of opinion here.
12:47 is it just me or is his engine crank a bit crooked/out of round/bent? 🙂
That was a fantastic segue at 5:17. Chef’s kiss.
Interesting. 👍
Question. How does hydrogen behave in aviation engines?
Can i use avgas in my car without damage. cat delete pipes for racing only.
Another great video. Thanks
Hey Paul, I thought there is a heavily bearded guy from GAMI who is pushing a version of 100 UL. George Braly I think. He sounds legit. OR is this for part 2 or your series and I am spilling the beans?
In defense of the old Caddie you have to remember it (most likely) was a flat head with side valves. Because of that long pancake shaped combustion chamber it couldn't have enough compression to make much horsepower. For it's day it was a pretty good performer.
2:38 what’s worse than that?
2:25 I like the rubber connecting rod! Lol
In your animation I noticed your crankshaft was just out of center how does that work it probably doesn't.
Yay, Paul is back!!!
Detonation is aggravated by high cylinder temperatures. Liquid cooling would be a big help.
High PISTON temperatures, IMO. Cooling pistons is tad more challenging than cooling cylinders - in cars it is achieved by "spraying" oil onto the inside of a piston, but AFAIK it is only used in high performance/ sport cars.