Seems to me they just scaled the plot to show change. I think the numbers are meaningless. Maybe zero point crossing at the average level of all data points.
GAMI vs Swift UL fuel competition
- Thread starter Tokirbymd
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Seems to me they just scaled the plot to show change. I think the numbers are meaningless. Maybe zero point crossing at the average level of all data points.
Awesome! They do link the study (which I'm not going to read).
https://www.researchgate.net/public...d_Aviation_Gasoline_on_Blood_Lead_in_Children
Checkout_my_Six
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Emotion will run this one into the ground.....
Geez I still remember what leaded auto exhaust smells like. Many of us grew up with this and lived to tell. Have we gotten a bit carried away with this?
Geez I still remember what leaded auto exhaust smells like. Many of us grew up with this and lived to tell. Have we gotten a bit carried away with this?
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I think over all of the threads regarding GAMI 100 approval it has been a theme to point out that the only likely way to get FAA off the X is to get Congress involved. If Quartz (which is not necessarily a serious journalism outlet)is putting out articles, it seem like the issue may be entering the zeitgeist. For better or worse.
regarding "grew up and lived to tell", check out this rabbit hole: https://en.wikipedia.org/wiki/Lead–crime_hypothesis
regarding "grew up and lived to tell", check out this rabbit hole: https://en.wikipedia.org/wiki/Lead–crime_hypothesis
Survivorship bias.
The fact is lead is bad. And even if research could show that lead from burning 100LL is negligible next to "background" lead exposure it wouldn't matter to the public. Most people believe leaded gas doesn't exist anymore. It's an easier target and makes GA vulnerable. I know when I was first getting into aviation I was shocked to learn that leaded gas was used.
Neil Rubin
Pre-takeoff checklist
This article from AOPA gives a pretty accurate description of the state of play: https://www.aopa.org/news-and-media/all-news/2022/june/pilot/unleaded-avgas
The two other players right now are Phillips/Anton and Lyondell/VP. The box at the end of the AOPA article lays out the different technical approaches taken by each of the four players. GAMI and Swift are both currently pursuing an STC-based approach to approval. Both have been working on more-or-less their current candidate fuels for many years. Phillips/Anton and Lyondell/VP are both participating in the reorganized FAA PAFI program (after the Shell PAFI entry and a different Swift fuel essentially failed in the original PAFI program) and are actively pursuing ASTM specifications for their proposed fuels.
Half Fast
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So is the FAA delaying the GAMI STC in order to give Phillips and Lyondell time to catch up? Maybe Congress will begin to raise hell, at least until the appropriate palms are greased (with an unleaded lubricant, of course).
Checkout_my_Six
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I've said this before....why aren't they looking at mechanics for lead poisoning? They are exposed the most. What is the problem we are trying to fix?
"They" are: https://www.cdc.gov/niosh/hhe/reports/pdfs/2012-0115-3186.pdf?id=10.26616/NIOSHHETA201201153186
In that case, blood lead levels were not found to be elevated - but adults tend to wash their hands before eating.
Half Fast
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But that's not the answer they're looking for. Don't confuse science with politics. Only studies designed to show the desired result are admissible.
Neil Rubin
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I have no idea at all why FAA headquarters is holding up the broad GAMI STC AML approval. It's frustrating that the process is not more transparent, largely because of the decision to maintain the confidentiality of vendors' proprietary information.
I do know that there is a lot more to picking the "right" fuel than whether it passes detonation tests and demonstrates compatibility with the fuel systems and materials in a handful of aircraft models. Toxicity of the replacement octane enhancers, effects on engine reliability (e.g. metallic deposits from the Phillips fuel), effects on emissions, fuel system compatibility in the wider fleet, cost, IP licensing terms, etc., all matter. There are real tradeoffs here, and at some point one of these fuels is going to become the standard that we are all stuck with for a long time. I'm really eager to see the lead gone, and I'm sympathetic to the eagerness of folks like GAMI and Swift to see a return on their investments before their patents expire. But, I also see the value to giving a variety of fuel technologies a shot, rather than have the whole industry latch on to the fuel that gets through a testing program first.
Now, is it appropriate for the FAA to slow down approvals for contenders that have been working on fuels for years to give more recently developed alternatives a shot—assuming that is actually what is happening? I don't know. But, I'm also not sure that having members of Congress—who aren't privy to the proprietary testing and other technical information the FAA has access to—push for one fuel over the others is really going to help matters in the long run.
Half Fast
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That is the STC that GAMI is trying to have approved. All piston engines that need 100 octane or less.
Tantalum
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Do the Diamond aircraft suffer any performance deficit as a result of their JetA burning engines?
I think the "diesel=bad" thing is no longer relevant. 10-20 years ago, yes, but not today.
I didn't necessarily say bad. But an aircraft should be designed around the engine. The Archer DX that came to mind when I made the comment was not. It's lazy engineering and/or lack of capital on why they keep altering the same nearly 50 year old design. They announced the pilot 100i. A 3 seat archer trainer. Limits it's second life after the school is done. And CAE along with piper announced they're going to make the Archer electric.
It's no wonder you see Cirrus and Diamond blow past what Piper has been selling.
Tantalum
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Indeed. I learned on and did all my initial flying and training on pipers and I've always been partial to low wings. One thing I thought they did right was build a trainer that didn't really feel like a 'trainer', you had a rudder trim and it shared many aspects with their more step up models. The same can't be said for their 3 seater unfortunately
Pinecone
En-Route
My other question is, how many people were tested and was each round of testing the same people or other people.
Half Fast
Touchdown! Greaser!
As I understand it, the FAA specified tests that would address the technical items you mention (octane enhancers, engine reliability, compatibility across the fleet, etc.), GAMI's fuel was tested with FAA oversight, and the FAA technical experts have recommended approval. That should be sufficient to issue the STC.
The other things you mention, such as cost, IP licensing, and so on, are NOT in the FAA's swim lane. Neither is holding up an STC to "give a variety of fuel technologies a shot." Those are business concerns that should be settled in the free market, not in a bureaucrat's closed-door office.
Nothing forces the "whole industry to latch on" to G100UL. In fact, approving the STC does not stop the EAGLE program, and other businesses are still at liberty to develop a fuel. If a fuel is created that does not require license fees, fuel suppliers may choose to sell it rather than GAMI's juice and offer it at a lower price. Competition is a good thing, and the FAA has no business keeping a viable competitor sidelined. This is how the free market works, and the FAA needs to get its heavy, dirty thumb off the scale.
Checkout_my_Six
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I usually jump to nefarious activities....but, unfortunately this one is a case of a bureaucratic mess. Changing of the guard throws a wrench into things and can bring things to a stop till the new guys are convinced to sign.
Pinecone
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I haven't run the performance numbers for the two engines, but the AVGAS engine is 180 HP Lycoming IO-360. The diesel is 168 HP, so there would be some performance loss, unless the diesel is lighter than the AVGAS engine.
Found some comments, the diesel version has a 7 knot higher flaps up stall speed and a 11 knots higher flaps down stall speed. It just makes the 61 knot flaps down stall speed cutoff.
Pinecone
En-Route
As long as all the candidates are fully mixable with each other and with 100LL, let the market sort them out.
Who can deliver the required amount of fuel to the most airports at the cheapest price, wins.
Who can deliver the required amount of fuel to the most airports at the cheapest price, wins.
Half Fast
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The two aren't mutually exclusive.
Maybe this situation is a nefarious bureaucratic mess.
Tantalum
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Have to also consider the torque values and the overall operating envelope of the engine, additionally, those diesels are turbo and full FADEC. So, by the time you hit 5K that 180hp avgas engine is already operating at around 140 hp or less.. in the meantime that diesel is still churning out its rated power. The fuel consumption is also worth note, the DA62 will cruise at 8gph combined. What other 7 passengers GA twin will cruise at 170 knots on such little fuel burn?
SoonerAviator
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As mentioned, the performance loss is probably minimal especially at at higher density altitudes. The turbo diesels sip fuel compared to the gassers, so you can fly with less fuel to offset the increased weight of the diesel engine/gearbox. It's probably a wash overall. However, the cost of the diesel powerplants/gearboxes is what is a bit cost-prohibitive at the moment. If they did mass adoption to get engine production volumes up, it would pencil out a bit better. Not to mention Jet A being cheaper for operating costs as well.
hindsight2020
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wrench-throwing by *bureaucratic proxy isn't a bug, it's the feature. The *latter's stipulated-as-necessary existence, is the nefarious intent in the first place.
First time dealing with the concept of 'plausible deniability' from self-interested actors in life? Check your lunch then, you might be getting it eaten again.
#MOSAIC #lulz #RuntheClockOffense
First time dealing with the concept of 'plausible deniability' from self-interested actors in life? Check your lunch then, you might be getting it eaten again.
#MOSAIC #lulz #RuntheClockOffense
STEVENTUCKER
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isnt 100R also fully mixable?
John Spartan
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Jet-A is superior in all ways except US availability. Better economy. Less pollution. Wish more than Tecnam and Diamond were pushing it in the market.
But it stinks.
John Spartan
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Small price to pay for those birds that cruise 1000 nm per tank.
It's heavier. And very few non turbines out there that can run it. The few diesels out there are significantly heavier themselves. Cd-300 is 150 pounds heavier than the io540
The small turbines guzzle at twice the rate
Pinecone
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But it is only usable in 85% of the airplanes out there. G100UL is usable in all airplanes right now.
John Spartan
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And still gets better mileage. A lighter diesel would be great. Rotax is future anyway. I’m just whining about my love of diesel. Uselessly no doubt in this case.
And still gets better mileage. A lighter diesel would be great. Rotax is future anyway. I’m just whining about my love of diesel. Uselessly no doubt in this case.
Any improvement in "mileage" and cost savings will be offset by maintenance expenses. At least in the current environment with the current engines available.
I flew and maintained both a DA40 and a DA40NG and would take the DA40 over the NG every single time. And this is coming from someone who works in diesel engine development so I have every reason to want to see a diesel option succeed. Unless things change significantly, they won't.
455 Bravo Uniform
Final Approach
Why do you say that?
I'm not sure what part you want to know about, but my favoring the DA40 over the NG is as much about the differences in the DA40 and DA40NG airframes as it is about the diesel engines.
As far as the diesel engines go, there are enough significant ADs and parts replacement requirements that the novelty and "good mileage" of the diesel will wear off quickly. The common Lycoming and Continental engine options, although dated, are easy to maintain on condition with relatively little headache. One of the problems I see with the diesels is the assumption that they're going to be able to be maintained in a similar fashion to what people are accustomed to with the legacy engines when that is not a realistic approach.
455 Bravo Uniform
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It was the engines part. Thanks.
STEVENTUCKER
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see i read that as well but after googling it gami is not available anywhere and it is UL94 thats availabe 85% of the country
ateamer
Pattern Altitude
Sold at 29 airports doesn’t exactly make it widely and easily available. Here in Florida - the third most populous state - there are all of three places to buy it.
