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FAA approves hundreds more engines to use unleaded avgas
- giantg2 5y agoNow can they up the weight limit for electric ultralights (300 lbs so it's the same as a full tank of gas) or not include the batteries towards the limit?
- p_l 5y agoWhy should they discount battery weight from the limit given that you do not lose that weight and thus it counts for all the reason weight limits are involved?
- giantg2 5y agoThat's not actually that's not true. ICE powered ultralights are weighed without fuel. The fuel limit is 5 gallons. So while the empty weight (in the regulations) is 254 lbs, the expected weight ready to fly is 300 lbs with fuel. Since the batteries don't have empty/full weights, it makes sense that they would increase the limit for electric ultralights to 300 lbs. This does not include weight added for safety devices in the event of catastrophic failure (eg ballistic parachute). Also the main reason for weight limits (including fuel limit) is to limit potential damage in the event of a crash. This is through a limit on kinetic impact (in addition to weight limit there is a speed limit) and hazardous material (the gasoline). So if we eliminate the highly flammable gas, then it's possible the battery weight doesn't really matter because a 254 lbs airframe will be physically limited in the weight of batteries that it can support.
- NelsonMinar 5y agoGAMI is a really neat company. This fuel additive is only one project; they're also famous for selling tuned fuel injectors to improve engine performance. https://gami.com/ https://gami.com/
- ericpauley 5y agoInteresting to see the continued interest in G100UL on Hacker News. Personally I'm ecstatic to soon be able to run unleaded. I'm curious to know if this is indicative of a broader (politically-relevant?) interest in getting lead out of GA, or just the sort of specialist topic that tends to interest HNers. It's interesting (but not unexpected in hindsight) that this new slew of approvals (generally) only impacts engines previously approved for low-octane unleaded fuels (e.g., 94UL). Even smaller engines like the Lycoming IO-360 (except the derated -L2A) aren't approved despite only modest power increases over the O-360. At any rate if GAMI is to be believed this is all academic because the final set of approvals should come out before G100UL is practically available anyway.
- VLM 5y agoThe entire topic is a virtue signalers paradise. Insert unscientific outrage in the vending machine, get free karma. No need to know anything about the specific topic or the environment or chemistry or aviation or statistics to get that sweet karma.
- base698 5y agoIf it hasn't been out five years you're a test pilot.
- drzoltar 5y agoI think a big factor here is the sentiment of people who live near small airports. The noise is already an issue. At least now there won’t be lead raining down on the neighborhood, so maybe less petitions to close the airport. As well, every time I test the fuel on a Cessna it inevitably sprays everywhere so there’s that worry too.
- downrightmike 5y agoIf you look at Chandler Az's small airport, you'll see it is now in the middle of a dense sprawl of suburbs, who no doubt have no idea leaded fuel it burnt over their heads day and night. Minimum house price in the areas wasn't less that $500k last time I looked, and those were few. Intel is just to the west. https://www.google.com/maps/place/Chandler+Municipal+Airport/@33.2793057,-111.8499411,12.75z/data=!4m5!3m4!1s0x872baafcb69fb1b3:0x6347ef40ce6a7333!8m2!3d33.271614!4d-111.8133 https://www.google.com/maps/place/Chandler+Municipal+Airport...
- notJim 5y agoCan the availability of this fuel be scaled readily, or will most people be stuck with leaded fuel still? Can companies other than GAMI make this fuel?
- ericpauley 5y agoGAMI claims the licensing for this will be relatively open, and Avfuel (very strong presence in GA fuel) claims they'll be pushing this out, so at least in theory it could see relatively rapid adoption.
- sokoloff 5y agoGeorge Braly (principal engineer at GAMI) has also claimed that all ingredients are readily available to and capable of being processed at any refinery currently making 100LL.
- Rutledge 5y agoI'm excited about this push. One interesting note is how this entire project has been 'in flight' for 30+ years almost cancelled with PAFI and then with then with recent pressure to close airports (namely KRHV) with leaded fuel as the lighting rod the FAA has now accelerated to “progress at the speed of light.” "He added that the accelerated commitment reflects new urgency arising from the FAA’s awareness that some local governments are taking action to ban leaded avgas from being used at airports in their jurisdictions. Local governments threats driving innovation at the federal level :P
- redis_mlc 5y ago> recent pressure to close airports (namely KRHV) with leaded fuel It's always been a real estate issue with KRHV. The nearby busy highways emit vastly more emissions than trainers, likely including lead. What city councils refuse to acknowledge is that once you close a city airport, you can never build another one. This is especially an issue in an earthquake zone.
- themitigating 5y agoWhat lead is coming from a highway?
- anonymfus 5y agoFrom car paints and tire balance weights.
- sokoloff 5y ago“Unleaded” fuel is permitted to contain up to 50mg per gallon*; though this is a limit, none is permitted to be intentionally added. 100LL by comparison contains 550mg per gallon by intent. * Sorry for the crazy mixed units; I didn’t write the regulations.
- redis_mlc 5y agoThere's likely trace elements in fuel. In the case of that area, the Capitol Expressway is a very busy highway system. If RHV air quality is monitored, then so should some locations around the highway. In fact, there's enough cars surrounding the airport that it would influence air quality measurements inside the airport perimeter. I mentioned the quake issue because I have seen documentation that RHV is part of the emergency response plan for transporting relief cargo.
- drzoltar 5y agoHave there been any publicized studies done on the reliability of aircraft engines, with and without lead? I’m guessing this is what made the transition take so long, but I can’t seem to find any references.
- p_l 5y agoAnother problem is, IIRC, that many replacements for leaded fuels have evaporation & performance issues at lower pressures that don't matter in a car but can be critical in airplane (it's even worse with ethanol additives, IIRC).
- strangemonad 5y agoIt’s a rather complex topic with all sorts of factors including economics of a small market and FAA red tape. Av web has a great multi part on failure modes of engines and why new engines often don’t succeed https://youtu.be/mwpzTnLC8BY https://youtu.be/mwpzTnLC8BY https://youtu.be/_k1TQGK3mZI https://youtu.be/_k1TQGK3mZI
- phoenix3200 5y agoThere are some claims out there that engines run better without lead (it eats away at seals and whatnot).
- ericpauley 5y agoAlso fouls spark plugs, sticks valves, contaminates oil, and covers the underside of the plane. Leaded avgas is all-around nasty stuff.
- hugh-avherald 5y agoI can't find it, but NASA concluded that piston engine reliability is generally a mystery.
- p1mrx 5y ago> some local governments are taking action to ban leaded avgas from being used at airports in their jurisdictions. What happens if a 100LL aircraft lands at such an airport? Do they have to disassemble/tow it, or is there some sort of financial penalty?
- lamontcg 5y agoFrom what I can google it looks like they ban the sale of leaded avgas at those airports. If you run out of gas at one of those airports I imagine you're purchasing it elsewhere and one way or another arranging for it to be delivered to you at the airport at your expense + hassle.
- downrightmike 5y agocan't it just run unleaded, albeit with slightly less power?
- p1mrx 5y agoI assume based on this article that running unleaded would have violated FAA regulations.
- Robotbeat 5y agoI honestly think there should be civil consequences for the FAA slow-rolling the sunsetting of leaded avgas. Red tape is causing very real harm to vast numbers of people.
- brendoelfrendo 5y agoAs with many problems with hard-to-see externalities, I think the FAA can't win here. If a plane falls out of the sky because of a fast-tracked approval, or people go out of business because of a fast-tracked ban, then the FAA is the bad guy. The number of people with the ability to assess the impact of atmospheric lead is much smaller.
- 5y ago
- stefan_ 5y agoIt's 2021. There is no excuse to be using leaded fuel, just as there was none 10 and 20 years ago. If they don't want to implement reforms, the obvious consequence needs to be close down any operation still using leaded fuel immediately. You had plenty of time. Leaded fuel is an obvious externality. As with all of those, there is no pressure on the ones causing the immediate harm to stop. Government action is required.
- nawgz 5y agoIt is very strange to see this downvoted. It is very inexcusable that after removing lead from virtually every other source due to its intense long term damage, we let people who fly thru the air spew it out in not-insignificant concentrations from the sky!! For such a heavy particle, I can’t imagine a more efficient strategy to distribute it widely than exactly that. It is not good to see the cognitive dissonance needed to downvote someone calling that out just because you like aviation on Hacker News. Maybe on an aviation forum I’d understand but here?
- p_l 5y agoThe problem is that there's no unleaded fuel that works as full replacement for the low-lead AVGAS, to the point that there are airports where using MOGAS could be considered deliberately inviting disaster. As far as I know, unleaded avgas is quite hot topic in aviation fuel research, but when optimizing for "planes not falling from the air" speed of change can be sometimes slow. Personally, I can't wait for when we get unleaded replacements for all leaded fuels and can just ban leaded.
- imoverclocked 5y agoThat’s only a problem because of the extremely old engine designs which we still use because of the expensive certification process for existing aircraft and new engine designs. We can design much better engines in just about every metric… and we do, just not for relatively cheap and certified GA aircraft. We actually do have 100LL alternatives and have had them but the missing piece has largely been certification of those fuels or even just carrying mogas for planes that are able to burn it.
- gengelbro 5y agoGreat news! If we could then get a decibel limit on the planes than essentially all my hangups with amateur aviation are resolved.
- mmaunder 5y agoThere are some interesting Diesel engines in aviation now like the Diamond DA42 and 62. They run on Jet A and are basically Diesel engines. Jet A and diesel are similar.
- phoenix3200 5y agoAren't those engines rather difficult to overhaul? As in, you have to send them to Europe?
- 535188B17C93743 5y agoYes, they're twice as expensive and basically impossible to overhaul––it's basically buying anew.
- dghughes 5y agoI'm sure many people who don't fly aircraft are not aware of the pre-flight check procedure part of which is to check the fuel. There is a small graduated cylinder with a spike at the top it is pushed into a valve under the wing to get some fuel from that tank. You look to see if there is any water floating in the gas. After you check it you toss the leaded gas on the tarmac. Then you do the same for the other wing tank. Airports especially small airports with piston powdered light aircraft using leaded avgas must be soaked in 70 years lead.
- mmaunder 5y agoI’m a pilot and use a GATS jar that lets me separate out water and toss the fuel back in the tank. Tossing fuel on the ramp is frowned upon at some FBOs.
- ericpauley 5y agoSame, it amazes me how many people around my airport don't use these. In my mind they enhance safety too because I can sump more gas and sump all the tanks at once, so if one tank is all water I'd know.
- stevehawk 5y agoOn the other hand the FBO could accidentally put in jet fuel and not realize it.. and it could be done in such a proportion that your eyes won't notice it in a gats jar.. the best way to test it is either to dip a paper towel or toss it on the ground
- sokoloff 5y agoThe screen on the GATS jar is for testing for Jet-A contamination. Gas evaporates cleanly off the screen. Jet leaves a film in a random pattern as it evaporates. https://www.pooleys.com/shop/pooleys/the-gats-jar-fuel-tester/ https://www.pooleys.com/shop/pooleys/the-gats-jar-fuel-teste...
- GekkePrutser 5y ago
- 1970-01-01 5y agoA hidden gem in the approval is the ability to finally use synthetic oil and extend the oil service interval: https://youtu.be/mhMKTe3tkv0?t=4223 https://youtu.be/mhMKTe3tkv0?t=4223
- inamberclad 5y agoI hope this brings down the cost per hour a little. Not as much as electric small aircraft will, but anything helps!
- aliswe 5y agodo you have tips for further reading about the part with electric aircraft cost per hour?
- inamberclad 5y agoNo, but nearly all of the cost associated with aircraft operations is either fuel or maintenance. On a light aircraft like a C-172, the only moving parts are the control surfaces, a couple gyros for the avionics, and the engine. Remove the engine and 99.9% of the fuel costs and 95% maintenance costs (avionics aren't cheap, but modern ones are more reliable) also go.
- tantony 5y agoHopefully they approve IO-550s soon as well.
- birktj 5y agoNo we just have to wait until they start approving engines to use synthetic and/or bio-based avgas. Then we can finally have carbon neutral flights in existing aircraft.
- hannob 5y ago> and/or bio-based avgas. Bio-based is a minefield of a few ways to have it reasonably ok'ish (mostly if it's stuff that would otherwise be waste) and countless ways to produce more emissions than before. The latter is usually what happens...
- GekkePrutser 5y agoHere in Europe the turbodiesels seem to be more popular as an alternative. But it's still pretty hard to get them approved. And I believe they require a full replacement instead of a rebuild every few years. I think it's highly preferable because many airports don't really want to be selling avgas anymore, and this will only become more of a problem as it's phased out. There's also a huge price difference.