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Going to the Moon Was Easy Compared to 100UL
- PaulHoule 6y agoSustainable aviation fuels are 50 years behind motor fuels because of the fear that changing fuels could cause your engine to fail. For ground transportation we have methanol, ethanol, butanol and other ol's not to mention biodiesel, dimethyl ether, etc. Electric is a good option too. For aviation fuel people are so scared of change that they are still trying to synthesize chain hydrocarbons from H and CO. (It's the one case where iron works as a catalyst but so poorly that they wish they could use Platinum instead.) Desperate people such as Nazis and South Africans found that's not worth doing even if you have cheap coal. Now people want to capture CO2 from the air to do it. Yeah right.
- marcosdumay 6y agoIt may be perfectly fine if you have cheap solar. It's a completely different problem from starting with coal. Anyway, there are planes that use ethanol internal combustion, and methane reaction engines. There have been for ages. Those fuels aren't widely used because they are hard to handle and lose performance on the normal passenger transportation conditions. The reason they are more common on cars is because performance matter much less on road transportation, not because of any lack of testing.
- PaulHoule 6y agoI think it is not a different problem. The FT process depends on many different paths, some of which build up larger molecules and some of which break them down. If you insist on making liquid hydrocarbons you need to be balanced on a knife edge -- HCs like to polymerize towards polyethylene (violently, blow up the container so) or break down to methane when heated. Thus you need a big factory to make a small amount of product and you might need to shut it down when the reaction vessel gunks up with petroleum jelly. With solar and carbon capture now you need to run an aniline stripper and a hydrogen factory but people dont care because of unicorns, rainbows, and all that.
- sokoloff 6y agoThere’s some element of fear as embodied in the aviation regulations. There’s not as much fear in the owner/pilot population, in large part because of those regulations. If any of the 100UL candidates pass certification, it’s a fair bet that they’ll be safe and I’ll have no concern with flying on them. The real issue is that while you can suffer a 10% power or energy-density reduction (such as from alcohol displacing gasoline in the fuel) in an automotive application without any appreciable loss of safety and minimal loss of functionality, the same is not true for aircraft. Piston aircraft takeoffs are always* done at maximum available power and a 10% loss of power is cause for an abort. So it’s unlikely that a fuel with materially worse performance would be certified. * - There were some extremely old multi-engine transports which had tables for reduced power takeoffs and some pilots mistakenly do them today, but the overwhelming practice is 100% of available.
- labawi 6y agoMaximum power takeoff seems reasonable, and unexpected 10% power loss would be a very good reason to abort, but I don't see why you couldn't trade (stable and safe) 10% power for 10% runway and clearance, maybe some weight, altitude .. You would need to reassess and update your tables, so regulations and certification are a big issue, but I don't understand why would it be technically unrealisable. Half a century after we know it's harmful seems a long time to stop spewing lead all over the place.
- sokoloff 6y agoLegally, you would have to do certification tests on every airplane type again. A 10% loss of power would require much more than 10% increase in runway for a given weight. Further, a 10% loss of energy density would require heavier takeoff weights for any given trip, meaning the penalty is further increased. I’m already weight-limited (either by certification limits or runway performance) on some flights. I carry about equal mass of fuel and people on trips with the whole family aboard. I’m not crying about it and I hope to see a viable 100UL emerge, but a 10% loss on two variables in the fuel would result in a lot more than “just use an extra 300 feet of takeoff roll and she’ll be a’ight”.
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- snovv_crash 6y agoSASOL is still alive and well... Cheap coal into liquid fuel is not particularly environmentally friendly but as a chemical process perfectly viable.
- PaulHoule 6y agoI think it was the worst performing stock in much of 2020.
- snovv_crash 6y ago2020 also had extremely cheap oil...
- pfdietz 6y agoIsn't one of the big uses of FT the production of synthetic motor oil? There is another process for synthetic gasoline that goes through methanol, which is reformed to hydrocarbons (with lots of aromatics) on zeolite catalysts.
- baxtr 6y agoCould anyone explain what 100 UL stands for? I tried this famous search engine u know, but that wasn’t very insightful...
- blktiger 6y ago100 Octane Un-Leaded
- Reason077 6y ago100 = 100 octane, a common octane rating for avgas (aviation gasoline) UL = unleaded.
- sokoloff 6y agoAlso worth noting that while the lean octane rating of avgas is 100 (as compared to auto fuel’s lean rating of around 85), the rich octane rating of avgas is around 130, providing increased margin against detonation on high-power takeoffs. It’s a mistake to think “I can buy gas labeled as 93 octane at my local Shell station; surely they can find a way to find just 7 more points or detune the engine slightly.”
- 51Cards 6y agoClicking on this article with no context makes it very difficult to understand if you don't already know what 100UL and avgas means. Took me 2 paragraphs of confusion to figure out "avgas" is aviation fuel and 100UL means 100 Octane Unleaded.
- umvi 6y agoIndeed, I kept waiting until the part where unsigned long types came into play but it never came
- u8mybrownies 6y agoAgreed - the sarcastic colloquial style is difficult to penetrate
- studius 6y agoI'd seen a gas pump with 100UL before, years ago, otherwise I would've had an even more difficult time interpreting it.
- throw0101a 6y agoAt the top of the page they say "WORLD'S PREMIER INDEPENDENT AVIATION NEWS RESOURCE". The author assumes that if you're reading AV Web, then you're already somewhat familiar with the aviation scene and some of its jargon. We're not talking about an article published in the New York Times or Forbes here.
- camkego 6y agoI second this, I had to really read the whole article before I totally got the big picture. A little context explaining ought to be done near the start.
- aaron_m04 6y agoYes, the title is clickbait.
- Reason077 6y agoThe problem isn't so much the fuel, it's the ancient piston aircraft (or at least, ancient engine designs) that are still kicking around. There are modern piston aircraft engines that not only run fine on unleaded fuel [1], but are even certified to run on standard automotive fuel ("Mogas"). There are videos on YouTube of pilots landing on remote highways and pulling up to regular gas station pumps to refuel their aircraft! [1] https://en.wikipedia.org/wiki/Rotax_912 https://en.wikipedia.org/wiki/Rotax_912
- sokoloff 6y agoVery few piston airplanes above the entry-level and trainer fleet are normally aspirated. The piston airplanes that fly a lot (mostly in commercial service) are overwhelmingly turbocharged. Those are the ones that need the higher octane fuel (and the ones that burn the most of it). I could have bought paperwork (the Petersen STC) to allow my Cessna 182 to burn alcohol-free unleaded car gas. That is not available for the replacement engine I installed in that airplane nor for my current airplane (nor any turbo airplanes to my knowledge).
- Reason077 6y agoThe turbocharged variant of the Rotax, the 914, is also certified to run on unleaded / automotive gas: https://en.wikipedia.org/wiki/Rotax_914 https://en.wikipedia.org/wiki/Rotax_914 Fun fact: This engine also powers the USAF's Predator drones!
- sokoloff 6y agoWhich is tiny; it has 115 horsepower for 5 minutes and 100 continuous. That’s still trainer and entry level or 2-seat Cessna 152 sized engine and about 1/3 the power of a modern single-engine Bonanza.
- ericpauley 6y agoFor what it's worth, some kit planes are now using the Rotax 915iS (Newer injected variant of the 914) for 4-seaters [1]. This engine puts out 135 continous up to 15,000 ft. For comparison, a given Lycoming 161HP non-turbo engine (requiring 100LL) shouldn't run above 75% continous (120HP), and can't put out more than this above 9,000 ft [2]. [1] https://en.wikipedia.org/wiki/Sling_Aircraft_Sling_TSi https://en.wikipedia.org/wiki/Sling_Aircraft_Sling_TSi [2] https://encoreflight.com/wp-content/uploads/2017/06/Piper-Warrior-POH-PA-28-161-1977-1982.pdf https://encoreflight.com/wp-content/uploads/2017/06/Piper-Wa... Page 100
- ballenf 6y agoI had forgotten that we all did hate ABBA in the eighties. I mean that no one I knew could stand to listen to a single song all the way through. But now I kind of like them and had kind of fake memories of always liking them until the article’s statement. But obviously they were pretty popular even back then, so maybe it’s just the two of us. My real point is how I think the nostalgia around the band with movies and such kind of hijacked my brain.
- redis_mlc 6y ago> I had forgotten that we all did hate ABBA in the eighties. I asked a European guy about ABBA's popularity in Europe at the time they were megastars. He said they were just enjoyable and fun to listen to. Some of the Eurovision stuff I heard though, dunno.
- gambiting 6y ago>>The U.K.-based Innospec is believed to be the only remaining producer of TEL Well, as a semi-interesting fact, UK is one of the very few countries where (extremely limited) sale of actual leaded petrol is still allowed at a handful of garages around the country. Pretty much exclusively used by owners of classic cars which haven't been modified to run on unleaded fuel. The list of garages that still sell it is here: https://www.fbhvc.co.uk/fuels https://www.fbhvc.co.uk/fuels
- deleted 6y ago[deleted]
- orange_tee 6y agoWhen I learned this a while back it blew my mind. Why are people allowed to dump lead on habited areas for a hobby? I understand if it were allowed for some commercial use, but to allow it for some random Joe who just wants to dick about in the sky. It seems wrong. I think there would be an outrage if it was something well known. I was also curious how much damage it is causing and found this article which says 16 million Americans are potentially affected, those living close to airports. [1] In Europe all new training aircraft are using diesel(-like) engines now which run on jet fuel or even straight diesel. It's not exactly hard to make the switch. [1] https://www.scientificamerican.com/article/lead-in-aviation-fuel/ https://www.scientificamerican.com/article/lead-in-aviation-...
- leetcrew 6y agofor one thing, there just aren't that many of them. there are under 200k hobbyist pilots in the US, and they mostly fly small single-engine planes. it's a problem, but it's pretty far down the list of emissions concerns. see also: two stroke engines in lawnmowers, boats, etc.
- sneak 6y agoLead is an issue not because of the general fact that it is dirty pollution (like two-stroke engines), but because of the precise neurological effects of lead in human bodies specifically. There is a difference between sprinkling sulphur dioxide over an area and, say, plutonium.
- paulryanrogers 6y agoContinued use of leaded fuel over time means it can build up in the environment. Living near an airport now I'm reluctant to eat anything from gardens nearby.
- orange_tee 6y agoTwo stroke might look bad if it is burning too much oil but in terms of health affects it is nowhere near as bad as leaded petrol.
- pfdietz 6y agoOne can make any organic material from non-fossil sources with enough money. For example, one can make xylenes from sugar by demonstrated pathways (hydrodeoxygenation followed by reforming). p-xylene has been made this way as a renewable feedstock for making PET plastic. That chemical also has octane rating of 146 (RON) or 127 (MON). https://www.virent.com/products/gasoline/ https://www.virent.com/products/gasoline/
- jabl 6y agoThey want a high octane unleaded fuel, that also otherwise largely matches the existing fuel (viscosity, density, vapor pressure profile etc.). I don't specifically know what's wrong with xylene, but IIRC aromatics in general produce a lot of soot (PAH and other nasty carcinogens), which is why they've been steadily reducing the maximum allowable content in automotive gas.
- pfdietz 6y agoGiven that they are allowing lead in avgas I doubt a little soot would be showstopper.
- jabl 6y agoDepends. If there's so much soot it reduces time between engine overhauls, that might not be good. Then again, TEL causes shorter overhauls as well, so... Anyway, like I said, there's a boatload of other properties the fuel has to satisfy as well. If it were as simple as just switching to p-xylene, presumably they would have already gone down that route.
- studius 6y agoI see no argument as to why going to the moon was easier. That sort of title diminishes the sacrifices and accomplishments involved with going to the moon.
- nosianu 6y agoIt's not a theoretical question, we have the events and the outcomes, complete: The time it took from announcement to actually landing on the moon was shorter than the time it took from recognizing the lead problem to banning it from all fuel including aviation fuel. The second one already is longer. So whatever your model of reality, the complete model is reality itself and it proves that point. What else would be better for arguing than the actual real-world outcomes? If you want to say things like "but there were less people working on the problem" you are removing things from the real world to build a more limited model to fit your argument. Overall getting enough people to work on the problem is part of it. Including everything, which includes getting attention and resources devoted to a problem in the first place, the moon landing indeed was easier. I think it's not much of an argument that exactly that, getting a vast effort rolling and people and resources devoted to a problem, really is one of the hardest problems. It was pretty easily achieved for the moon landing. If you want to separate the policy problem of getting the resources from the technology problem you are only looking at a part, to get the desired outcome both are needed. Sure, the technology part was harder for the moon landing - which makes it even worse that the other part, the policy stuff, is so hard to accomplish.
- studius 6y agoHow many died? The elapsed calendar time from the birth of the first human to when an electronic drink blender was first invented was much longer, but I wouldn't say that was more effort and sacrifice than getting to the moon. Do you know how many lives were lost in Germany, prisoners marched in the cold by force, a huge number of them dying along the way, to dig underground missile production factories with their bare hands, being shot if they stopped? Or that those men leading those atrocious slave factories were then effectively saved from certain death from war crime tribunal, just to help with the early U.S. rocket program that went into the moon effort?[1][2] That's not even including the sacrifices leading up to it by the U.S. and the U.S.S.R., which I'd include in the overall effort[3][4]. [1]- https://en.wikipedia.org/wiki/Operation_Paperclip https://en.wikipedia.org/wiki/Operation_Paperclip [2]- https://amazon.com/Operation-Paperclip-Intelligence-Program-Scientists-ebook/dp/B00BAXFBI2 https://amazon.com/Operation-Paperclip-Intelligence-Program-... [3]- https://en.wikipedia.org/wiki/Category:Space_accidents_and_incidents_in_the_Soviet_Union https://en.wikipedia.org/wiki/Category:Space_accidents_and_i... [4]- https://en.wikipedia.org/wiki/List_of_spaceflight-related_accidents_and_incidents https://en.wikipedia.org/wiki/List_of_spaceflight-related_ac...
- jabl 6y agoIn my non-expert uninformed opinion, if the political will would be there UL94 would have replaced 100LL a long time ago. UL94 is basically 100LL but without the lead, so we certainly know how to produce it worldwide at decent cost. - Most planes could switch without any change - Yes, in some cases, changes would be needed, like - detuning. - installing an electronic ignition timing system. - Installing a new engine, either a newer gasoline engine, a diesel engine, or a turbine engine. - Scrapping the plane and buying a new one. Sure, this would incur cost for some, but c'est la vie. Many such decisions have been made in societies all over the world, often for good reasons. This could still be the solution if the EPA puts their foot down and the PAFI thing mentioned doesn't produce a workable 100UL recipe.
- beervirus 6y ago> Sure, this would incur cost for some, but c'est la vie. How easily we discount costs that affect only other people.
- hedora 6y agoLike 16 million cases of lead poisoning because people that can afford a plane don’t upgrade their engines?
- leetcrew 6y agothe actual quote from the scientific american article: > The EPA estimates that 16 million Americans live close to one of 22,000 airports where leaded avgas is routinely used—and three million children go to schools near these airports. 16 million people living near airports where leaded avgas is used is not the same thing as 16 million confirmed cases of lead poisoning. there's no need to exaggerate.
- the8472 6y agoSo merely 16 million people with subclinical heavy metal accumulation, which is tied to lower IQs and increased crime rates. Nice.
- CalChris 6y agoWhat is the status of fuels like 100UL in Europe?
- jabl 6y agoAFAICS GA is a much smaller thing in Europe, and European regulators have largely taken a lets wait and see attitude, and will presumably follow whatever the US counterparts will end up doing. 100LL is very expensive in Europe, and thus there has been more interest in diesel piston engines.
- sbussard 6y agoWarning: this article is known to the state of California to cause boredom.
- antattack 6y agoIt's time for airplanes that use leaded gasoline to go the way of xray machines for shoe fitting. Toxic products, such as leaded gasoline, asbestos, tobacco, some pesticides, would had been outlawed much sooner if US had universal healthcare where poisoning of others costs us all - instead of being an externality.