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Swift Fuel

Swift and Shell are competing to be the supplier of the substitute for 100 LL. I guess that it will be decided soon.
This description is from Swift Fuels:
?These tests show that our fuel is high performance and has a higher fuel density. That means the fuel is typically 0.5 to 0.8 pounds per gallon heavier than 100LL, yet it achieves a 7 to 15% increased range (i.e. flight miles) per gallon due to it higher energy density. This has significant favorable implications for many aviators, because it expands the reach of available refueling hubs during flight, a major flight safety improvement.?
So that means that, if Swift wins the contest, 20 gallons of their UL 102 would weigh 10 to 16 pounds more that 100LL, and 6 to 12 pounds more than mogas. I wonder if that will impact the amount of baggage allowed?
Swift claims a 7 to 15% increased range. Does that mean that the 912iS will burn 7 to 15% less fuel?
I hope to make it to Oshkosh this year and I will quiz the Swift fuel rep.
Regards,
Damien Graham
 
The FAA flight tests for both fuels was discontinued a few weeks ago. OSH should be interesting..... ;)

https://www.faa.gov/about/initiatives/avgas/

From that FAA link... I wonder if the weight per gallon is one of the issues/mitigations being resolved?

Differences in the two PAFI fuels as compared to 100LL are being evaluated for impacts and mitigations. While these issues are assessed, PAFI flight testing and some engine testing have been halted. Both fuel producers, Shell and Swift, are currently evaluating options to mitigate the impacts that these differences will present in fuel production, distribution, and operation in the GA fleet. These evaluations will take time and ultimately affect the schedule of the test program. Based on current projected activities and timelines, the testing completion date for the PAFI program will be December 2019 (previously December 2018).

Looks like everything is delayed a year.
 
Interesting we've heard nothing from Shell over here for almost 2 years now and that Swift has been selling their lower octane fuel for some time at something like 40 locations in the US now.

I can see how the higher specific weight fuel could cause issues with loading and gross weight and that becomes more problematical with a mix of 100LL and their fuel but surely we can hand the responsibility over to pilots to deal with that aspect as they are already responsible to proper and legal loading on their aircraft.

Sending the manufacturers back to the drawing board after all this time seem like a huge waste of time and resources and they'll have to repeat much of the testing already done. The weight issues were known about years ago with the Swift fuel. If it was a problem with the FAA, they should have said so from the start.

Aircraft converted to diesel, burning Jet A, have had to revise their loading data as well due to the fuel weight differences.
 
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Having read the PAFI update, it doesn’t appear to be a “back to the drawing board” statement, but rather a mitigating the differences between the two fuels to create a common standard.

I expect that once the gap analysis is completed, a common ASTM standard will be produced, followed by validation of that common fuel.

As for Swift fuel, noting the weight is about 10% more, but the BTU content is also about 10% more, it’s just a matter of loading less volume of fuel for the same range.

In reality, it adds the opportunity for additional range; that assumes the actual burn rate validates 10% reduction in GPH for the same performance setting.

As for price, San Carlos (SQL) has Swift - although they were out when I was there a month ago. The price was 20¢ a gallon more than 100LL. My guess is that the final price of UL avgas will be about the same as 100LL if accepted universally - even if it’s less expensive to produce...supply and demand rule.
 
Swift 102 price

Home base for Swift is Purdue University in Indiana. They are executing a marketing evaluation and recruiting airports to give away 102 just to get user feedback,probably for marketing use. They told me the target price is about $4 which is what 100LL costs at many small Midwest airports
 
In a perfect world, the 100LL replacement can be made street legal and the auto industry will embrace it to build higher compression and more efficient engines with longer range. This will lead to higher volumes and lower prices.

One can dream.

V
 
In a perfect world, the 100LL replacement can be made street legal and the auto industry will embrace it to build higher compression and more efficient engines with longer range. This will lead to higher volumes and lower prices.

One can dream.

V

That really would be nice. But I wonder if it will meet all the *other* pollution standards for cars, when run in existing engines and control systems. No way a/c engines meet automotive standards regardless of fuel, so the refiners might have just ignored everything but lead.
 
Having read the PAFI update, it doesn?t appear to be a ?back to the drawing board? statement, but rather a mitigating the differences between the two fuels to create a common standard.

I expect that once the gap analysis is completed, a common ASTM standard will be produced, followed by validation of that common fuel.

As for Swift fuel, noting the weight is about 10% more, but the BTU content is also about 10% more, it?s just a matter of loading less volume of fuel for the same range.

Ahh. That makes more sense. I suppose you'd have to be able to safely mix the 2 formulations also.
 
Having read the PAFI update, it doesn?t appear to be a ?back to the drawing board? statement, but rather a mitigating the differences between the two fuels to create a common standard.

.....

I'm not sure there needs to be a common standard.

You could buy 100NL and 100SW for example and your POH could approve both, but with different W&B and perhaps operating limitations as previously mentioned.

Unless the idea is to get one standard (100-REPLACEMENT) so an FBO can order either fuel each time he fills his tank. That interchangeability sounds very difficult (impossible?) with the energy density and weight/gallon differences mentioned so far.

Perhaps we'll see the Swift fuel "watered down" to the same density as the other stuff. :)
 
I'm not sure there needs to be a common standard.

You could buy 100NL and 100SW for example and your POH could approve both, but with different W&B and perhaps operating limitations as previously mentioned.

Most airports I know only have one set of tanks for AVGAS; that being the argument at my local airport as to why they don’t sell MOGAS. That alone would be the economic reason for a single standard.

The main reason for not standardizing on two standards (aside from driving engineers like me nuts with the duality) is that everyone has to account for it requiring extra tooling, knowledge, regulation, compliance, etc...[think SAE and Metric) The FAA could approve two standards, however, I think it is highly unlikely due to the added burden of multiplicity. And from what the PAFI update says, it appears they’re looking for one standard.

There needs to be one standard in order for the fuel to be economical. So yes, you could have two standards (think VHS and Betamax), but eventually one will win out for simplicity sake.

Even more so, note how many times folks have issue with putting Jet A into Avgas tanks or vice versa (it’s actually pretty common - especially if you own a Diamond Twinstar), now multiply that by a huge factor. I think dual 100 octane fuels would turn into a fueling crazy time.
 
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The only fuel (so far) that is completely fungible with existing avgas and still conforming is G100UL.

I have a feeling it will be to market sooner than the others now that the PAFI project has finally failed. Time will tell.
 
The only fuel (so far) that is completely fungible with existing avgas and still conforming is G100UL.

I have a feeling it will be to market sooner than the others now that the PAFI project has finally failed. Time will tell.

I disagree that the PAFI project has failed. The FAA states that the completion date has been extended to December 2019, which is to fulfill what was previously discussed.
 
Most airports I know only have one set of tanks for AVGAS; that being the argument at my local airport as to why they don’t sell MOGAS. That alone would be the economic reason for a single standard.

The main reason for not standardizing on two standards (aside from driving engineers like me nuts with the duality) is that everyone has to account for it requiring extra tooling, knowledge, regulation, compliance, etc...[think SAE and Metric) The FAA could approve two standards, however, I think it is highly unlikely due to the added burden of multiplicity. And from what the PAFI update says, it appears they’re looking for one standard.

There needs to be one standard in order for the fuel to be economical. So yes, you could have two standards (think VHS and Betamax), but eventually one will win out for simplicity sake.

Even more so, note how many times folks have issue with putting Jet A into Avgas tanks or vice versa (it’s actually pretty common - especially if you own a Diamond Twinstar), now multiply that by a huge factor. I think dual 100 octane fuels would turn into a fueling crazy time.

That wasn't really my point.

Think of it more like Shell vs. Mobil.

Your FBO stocks one or the other, as long as they can mix in your tank, it's up to the pilot to account for it.

If I want 10% more range with a little extra weight penalty I would just search for a 100SW FBO using airnav.com when I am on a trip. :)

I wasn't implying that one airport needs to sell both and have two tanks.
 
That wasn't really my point.

Think of it more like Shell vs. Mobil.

Your FBO stocks one or the other, as long as they can mix in your tank, it's up to the pilot to account for it.

If I want 10% more range with a little extra weight penalty I would just search for a 100SW FBO using airnav.com when I am on a trip. :)

I wasn't implying that one airport needs to sell both and have two tanks.

Well, ok, let’s suppose your airport stocks your favorite brand and you’re happy with that and you plan for that specific fuel usage. Unfortunately, it’s not as simple as Mobil vs Shell vs Swift. And you’ve hit on the crux of the matter - it’s fuel compatibility [there’s that standards thing...] When you get car gas, even from Bubba’s Gas N Go, it is formulated to a standard.

You decide to go on a little trip, but there are only two airports on your route of flight and both have the other brand. Can you mix the two fuels? Are they compatible? What happens if they react with each other in your tank and fuel lines? Do you need to drain your remaining fuel first? This is the big issue and the main question PAFI has to resolve. If both fuels can be made compatible, then a standard can be developed and then, well, boo yah, we have a fuel to use.
 
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Well, ok, let?s suppose your airport stocks your favorite brand and you?re happy with that and you plan for that specific fuel usage. Unfortunately, it?s not as simple as Mobil vs Shell vs Swift. And you?ve hit on the crux of the matter - it?s fuel compatibility [there?s that standards thing...] When you get car gas, even from Bubba?s Gas N Go, it is formulated to a standard.

You decide to go on a little trip, but there are only two airports on your route of flight and both have the other brand. Can you mix the two fuels? Are they compatible? What happens if they react with each other in your tank and fuel lines? Do you need to drain your remaining fuel first? This is the big issue and the main question PAFI has to resolve. If both fuels can be made compatible, then a standard can be developed and then, well, boo yah, we have a fuel to use.

Nah, I said "as long as they can mix in your tank" :)

Perhaps it's more like Pure Regular vs. 10% Corn+Regular.

Two completely different standards but it doesn't really matter which one you buy - and yes, one even has less energy density.
 
Two other important considerations haven't been mentioned here. They are perhaps less important to our smaller aircraft, but of some considerable importance to the larger piston aircraft in commercial service.

Two on-board systems are heavily reliant on the Specific Gravity of fuel. Capacitance-type fuel quantity indication systems and many fuel flow systems are only accurate when used with a single type of fuel.

If one were to introduce fuel with a new Specific Gravity and, even worse, to co-mingle it with fuel of another Specific Gravity, one would never be able to know how much fuel has been consumed or how much fuel remains in the tanks. This might seem trivial to us, but when loading a big piston twin, a 10% shortfall in fuel loading could eat drastically into reserves.

To put it into more practical terms, imagine flying your RV with capacitance fuel probes and a flow meter / totalizer. You are used to burning 8GPH of 100LL. You flight plan for that figure. What is your brain going to do when you lean at cruise and see 7.2GPH, or 7.6 GPH for the same power setting? When you look at your fuel gauges and think you've got 10 gallons remaining but you only have 8 in the tanks. What happens if your on-board systems don't interpret the change in fuel density as a direct 10% linear offset?

I know that, theoretically, all of this should be a wash. Heavier fuel by 10% that also yields 10% more range should mean the same number of miles to dry tanks. We, being humans, will undoubtedly find a way to turn this simple conversion into disaster.

My mind keeps going back to the infamous Gimli Glider, an Air Canada B767 that landed deadstick at Gimli, Manitoba, when a combination of issues with the fuel quantity indication system and compounding human errors around pounds/kilos/inches/centimeters/litres/gallons saw the airplane loaded with far less fuel than was needed to reach its destination. This scenario is likely looming large in FAA minds, and I can't blame them for being cautious in insisting on mitigation strategies before turning us loose on this new fuel.
 
Two on-board systems are heavily reliant on the Specific Gravity of fuel. Capacitance-type fuel quantity indication systems and many fuel flow systems are only accurate when used with a single type of fuel.

That's why capacitive systems on heavy aircraft have densitometers. Kerosene-based fuels vary widely in density based on temperature. But it's only a problem if you upload multi-thousand pounds of fuel. If you are worried about the small difference in Avgas densities you are cutting your fuel reserves too fine.
 
That's why capacitive systems on heavy aircraft have densitometers. Kerosene-based fuels vary widely in density based on temperature. But it's only a problem if you upload multi-thousand pounds of fuel. If you are worried about the small difference in Avgas densities you are cutting your fuel reserves too fine.

While I agree with your comments about densiometers in heavies burning heavy fuel, I would assert that a 10% error in fuel quantity sensing is a considerable error in small aircraft. It may equate to the entire VFR reserve amount. This could leave one landing with zero reserves when one felt they had the VFR minimums. Not good, and likely the reason why the FAA is insisting on mitigation strategies.
 
While I agree with your comments about densiometers in heavies burning heavy fuel, I would assert that a 10% error in fuel quantity sensing is a considerable error in small aircraft. It may equate to the entire VFR reserve amount. This could leave one landing with zero reserves when one felt they had the VFR minimums. Not good, and likely the reason why the FAA is insisting on mitigation strategies.

It would appear that 10% accuracy in normal use (ie, not at the zero fuel point) is within the Part 23 requirements -

(b)Fuel quantity indication. There must be a means to indicate to the flightcrew members the quantity of usable fuel in each tank during flight. An indicator calibrated in appropriate units and clearly marked to indicate those units must be used. In addition:

(1) Each fuel quantity indicator must be calibrated to read “zero” during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply determined under § 23.959(a);

(2) Each exposed sight gauge used as a fuel quantity indicator must be protected against damage;

(3) Each sight gauge that forms a trap in which water can collect and freeze must have means to allow drainage on the ground;

(4) There must be a means to indicate the amount of usable fuel in each tank when the airplane is on the ground (such as by a stick gauge);

(5) Tanks with interconnected outlets and airspaces may be considered as one tank and need not have separate indicators; and

(6) No fuel quantity indicator is required for an auxiliary tank that is used only to transfer fuel to other tanks if the relative size of the tank, the rate of fuel transfer, and operating instructions are adequate to -

(i) Guard against overflow; and

(ii) Give the flight crewmembers prompt warning if transfer is not proceeding as planned.


Note that my certified Tiger doesn't have actual numbers on the guage, just tick marks every 1/8 from E to F. This is from a later 1991 model with even less markings :) -

s-l300.jpg


Near zero, any capacitance measuring device would be measuring air and would meet the 'zero accuracy' requirements whatever the fuel density was.
 
While I agree with your comments about densiometers in heavies burning heavy fuel, I would assert that a 10% error in fuel quantity sensing is a considerable error in small aircraft. It may equate to the entire VFR reserve amount. This could leave one landing with zero reserves when one felt they had the VFR minimums. Not good, and likely the reason why the FAA is insisting on mitigation strategies.

You keep talking about mitigation, but I wonder where you get the idea the FAA is concerned about fuel density. In the communication regarding the progress of certification there is no mention of what "issues" require "mitigation". I think they are more concerned with the compatibility of the competing fuels, their performance, and the effects on the current fuel system sealing technology.
 
It would appear that 10% accuracy in normal use (ie, not at the zero fuel point) is within the Part 23 requirements -

(b)Fuel quantity indication. There must be a means to indicate to the flightcrew members the quantity of usable fuel in each tank during flight. An indicator calibrated in appropriate units and clearly marked to indicate those units must be used. In addition:

(1) Each fuel quantity indicator must be calibrated to read ?zero? during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply determined under ? 23.959(a);

(2) Each exposed sight gauge used as a fuel quantity indicator must be protected against damage;

(3) Each sight gauge that forms a trap in which water can collect and freeze must have means to allow drainage on the ground;

(4) There must be a means to indicate the amount of usable fuel in each tank when the airplane is on the ground (such as by a stick gauge);

(5) Tanks with interconnected outlets and airspaces may be considered as one tank and need not have separate indicators; and

(6) No fuel quantity indicator is required for an auxiliary tank that is used only to transfer fuel to other tanks if the relative size of the tank, the rate of fuel transfer, and operating instructions are adequate to -

(i) Guard against overflow; and

(ii) Give the flight crewmembers prompt warning if transfer is not proceeding as planned.


Note that my certified Tiger doesn't have actual numbers on the guage, just tick marks every 1/8 from E to F. This is from a later 1991 model with even less markings :) -

s-l300.jpg


Near zero, any capacitance measuring device would be measuring air and would meet the 'zero accuracy' requirements whatever the fuel density was.
What you've quoted is correct with regard to fuel quantity, but how many of us really care about quantity? I daresay it's just about nobody.


We use quantity as a rough proxy for duration (which we then translate into range if flying cross-country). If your fuel burn is based on a given power setting, and you find yourself using a fuel with lower energy density, you're going to burn more fuel (quantity/volume) to achieve the same power, resulting in your tanks being at a lower level when you're done with a flight of a given duration. You'll realize this a little bit short of your destination when your fuel gauge is lower than expected (the discrepancy, as shown on the gauge, will increase with time). Hopefully that'll be in an area with lots of convenient alternate landing sites (with available fuel!) along your route, and not in, say, remote Alaska.
 
Swift fuel

If the new blend burns as clean as the swift 94 octane I?m running in a o-300 in a c172 at kppo LaPorte, IN, I?m all for it. Inside the exhaust pipes it?s always a light tan color and at annual the spark plugs are so clean they don?t need bead blasted.
 
If the new blend burns as clean as the swift 94 octane I?m running in a o-300 in a c172 at kppo LaPorte, IN, I?m all for it. Inside the exhaust pipes it?s always a light tan color and at annual the spark plugs are so clean they don?t need bead blasted.

Welcome to the world of mogas users. ;-) I haven't dug lead out of a spark plug in a couple of decades.
 
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