20% consume 80% of the Avgas

focal_plane

focal_plane

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focal_plane
A thread to discuss the validity of the 20% of the fleet consumes 80% of the Avgas and that 20% requires 100 octane for High Performance Engines. There are various versions that are referred to, 30/70, 1/3 - 2/3 etc. I really would like to see the study and the data behind this. Was this a study from 20+ years ago? I don't know but the references I've seen like this seem to be at least 20 years old. When pressed for citation of the study/data, the response is "I heard, I think, I remember.......", just various forms of non-specific reference. So does anybody know where the study/data come from? I know it must exist.

I'm going to throw out some "I thinkisms" for discussion. There are Zero facts to back this up whatsoever.

I think The study was done a long time ago.

I think The study is no longer valid if it ever was even done in a scientific way

I think The number of High Performance Aircraft have diminished as that sector of the fleet has been transitioning to turbine engines. (Hmm, that really may be a stretch)

I think A single 100UL will be priced out of this world.

So, from the of my I thinkisms, you can clearly see my bias. Yes, I'd like to have 94UL or an equivalent available. Yes, we'll need 100 octane to support the HP fleet.

So, what's the solution? How could we have two Avgas options at airports with the expense associated? Small airports almost certainly wouldn't have the capital to do it. Larger airports might have the capital, but generally, "I think" that total Avgas sales wouldn't really increase at a given airport so where's the incentive? Maybe the EPA could give grants to a number of airports to, I don't know, 100 or 200 airports to install a second quasi portable/small Avgas fuel dispenser. Figure a million a pop so maybe $200M. Compared to the Trillions of dollars blown over the last few years for infrastructure/COVID etc, this is a pittance. EPA could claim wild success in getting lead out of much of the GA fleet.

Yeah, I know, that idea would go over like a lead zeppelin.
 
focal_plane said:
So, what's the solution?
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Close 2/3 of the airports, scrap the non-100UL fleet, hand out tax credits for the trouble, take credit for reduced emissions. #thereifixedit :popcorn:
 
What fraction of the low-performance fleet cannot use mogas?
 
focal_plane said:
So, from the of my I thinkisms, you can clearly see my bias. Yes, I'd like to have 94UL or an equivalent available.
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Are you biased against a 100UL option? If so, why? If not, then why are you biased toward 94UL?
 
I burned ~2500 gal of avgas last year. How about you?

My engine requires 100 octane fuel.

The price inflation on 6 seat high performance aircraft leads me to believe there's still a lot of people who want to operate them. They burn a lot of gas, and tend to fly a lot further than the o-360 crowd.

I agree that the 70-80% probably came from a time when beech 18's and cessna 340's hauled bank checks and film around every night, but I'd bet the number is still over 2/3's. There also used to be more cubs, taylorcrafts, and luscombs around, too.
 
iamtheari said:
Are you biased against a 100UL option? If so, why? If not, then why are you biased toward 94UL?
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I am not biased against a 100UL solution. I am biased against a 100UL Only solution. I believe that it will be priced so high that flying recreationally will take a big hit. If we see $8-$10 100UL as the only avgas available, I suspect I will not be the only one reducing or dropping out.
 
Jim K said:
I burned ~2500 gal of avgas last year. How about you?

My engine requires 100 octane fuel.

The price inflation on 6 seat high performance aircraft leads me to believe there's still a lot of people who want to operate them. They burn a lot of gas, and tend to fly a lot further than the o-360 crowd.

I agree that the 70-80% probably came from a time when beech 18's and cessna 340's hauled bank checks and film around every night, but I'd bet the number is still over 2/3's. There also used to be more cubs, taylorcrafts, and luscombs around, too.
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Some engines that require 100 really don’t. 160hp o-320s and 180hp o-360s are really 91 octane engines
 
Lively discussion, it's good. Real point here is what are the facts and data. I'm happy to listen to real facts and data. The anectdotal stuff is just old and tired. If it's really not anectdotal and there is real valid data behind it, I'll take my lumps.
 
I personally know of an operation with 4 cabin class Cessnas that's burning up to 80,000 gallons a year. A few operations like that makes up for a ton of bugsmashers.
 
focal_plane said:
I am not biased against a 100UL solution. I am biased against a 100UL Only solution. I believe that it will be priced so high that flying recreationally will take a big hit. If we see $8-$10 100UL as the only avgas available, I suspect I will not be the only one reducing or dropping out.
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I would certainly choose 91 or 94UL over 100LL. Between 91 or 94 or 100UL, I would choose whichever is cheaper.

Once 100UL is available, the only way airports will sell a lower grade is if it's enough cheaper than 100 to offset the cost of maintaining a second tank and pump... though if it's cheaper some very small airports (think grass fields and such that never see planes needing 100) might sell it as their only fuel.

If avgas gets super expensive, a lot more people will be getting mogas STCs and working out ways to get it ethanol free.
 
focal_plane said:
I am not biased against a 100UL solution. I am biased against a 100UL Only solution. I believe that it will be priced so high that flying recreationally will take a big hit. If we see $8-$10 100UL as the only avgas available, I suspect I will not be the only one reducing or dropping out.
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The problem is one of volume. Avgas for nearly any airport is not a high volume commodity. Having two variants just doesn't make financial sense to the airport or FBO.

As for the 20% figure, the vast majority of piston engine airplanes being used commercially need 100 octane and make up the bulk of the Avgas sales, buying fuel in the thousands of gallons per year. The regular Cessna/Piper/etc fleet, outside of training operators, just doesn't buy that much gas annually. I personally average about 10 gallons a month. No one is making a business selling Avgas to me.
 
midwestpa24 said:
The problem is one of volume. Avgas for nearly any airport is not a high volume commodity. Having two variants just doesn't make financial sense to the airport or FBO.

As for the 20% figure, the vast majority of piston engine airplanes being used commercially need 100 octane and make up the bulk of the Avgas sales, buying fuel in the thousands of gallons per year. The regular Cessna/Piper/etc fleet, outside of training operators, just doesn't buy that much gas annually. I personally average about 10 gallons a month. No one is making a business selling Avgas to me.
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Agree with first paragraph and said same in original post. But the remainder is back to the anecdotal vast majority uses thousands and Cessna/Piper/etc fleet just doesn’t use that much to justify the 20/80 “axiom.” It may be true but where’s the suppporting data?
 
midwestpa24 said:
The problem is one of volume. Avgas for nearly any airport is not a high volume commodity. Having two variants just doesn't make financial sense to the airport or FBO.

As for the 20% figure, the vast majority of piston engine airplanes being used commercially need 100 octane and make up the bulk of the Avgas sales, buying fuel in the thousands of gallons per year.
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I agree with your first point. When you could put a cheap fuel pump out on the ramp, having multiple fuels wasn't horrific. But with spill control and automatic billing, adding a pump is a serious investment that most FBO's don't care to make.

On the 20% thing, I'd love to see a modern study. I remember seeing a study in AOPA Pilot a long time ago - we're talking 20-30 years ago. Back then, people were flying Apaches, Beech 18's, DC-3's, and other piston stuff on daily freight runs. Crop dusters were still using a motley collection of stuff, some of which had piston engines. Fire fighters/tankers were using WWII bombers that drank 100LL by the hundreds of gallons an hour. All that stuff is gone. Freight goes on Caravans and other turbine powered aircraft. The recip fire fighting fleet has been retired. Crop dusters are all flying turbine equipment these days. And much of the charter/corporate world has gone turbine.

I just don't see these big users that require 100LL any more. I want to see a study - documented, verified, conducted in the last 3-5 years, 'cause I don't buy the claim.

OTOH, I don't buy the claim that 100LL is a real environmental hazard either, but it sounds like AOPA, EAA, FAA, FFA, CIA, NRO, BBC and everyone else has conceded that.
 
I flew in the Cardinal between 5-600 hours last year. That's about 5,000 gallons through our IO-360 per year.
 
kyleb said:
I agree with your first point. When you could put a cheap fuel pump out on the ramp, having multiple fuels wasn't horrific. But with spill control and automatic billing, adding a pump is a serious investment that most FBO's don't care to make.

On the 20% thing, I'd love to see a modern study. I remember seeing a study in AOPA Pilot a long time ago - we're talking 20-30 years ago. Back then, people were flying Apaches, Beech 18's, DC-3's, and other piston stuff on daily freight runs. Crop dusters were still using a motley collection of stuff, some of which had piston engines. Fire fighters/tankers were using WWII bombers that drank 100LL by the hundreds of gallons an hour. All that stuff is gone. Freight goes on Caravans and other turbine powered aircraft. The recip fire fighting fleet has been retired. Crop dusters are all flying turbine equipment these days. And much of the charter/corporate world has gone turbine.

I just don't see these big users that require 100LL any more. I want to see a study - documented, verified, conducted in the last 3-5 years, 'cause I don't buy the claim.

OTOH, I don't buy the claim that 100LL is a real environmental hazard either, but it sounds like AOPA, EAA, FAA, FFA, CIA, NRO, BBC and everyone else has conceded that.
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Could not agree more. Bring on the data.
 
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Nearly all turbos required 100LL. Both Turbo-normalized and turbocharged.

The stats people quote keep saying the majority are twins. Lots of single engine Cessna turbos and Cirrus's in the fleet.
 
I fly 200 or so hours a year burning ~14gph on average, so I burn my fair share. Can’t run mogas either, since I have a high compression O-470
 
focal_plane said:
I am not biased against a 100UL solution. I am biased against a 100UL Only solution. I believe that it will be priced so high that flying recreationally will take a big hit. If we see $8-$10 100UL as the only avgas available, I suspect I will not be the only one reducing or dropping out.
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How much fuel did you burn over the last year?

There is 94UL already and 91UL coming. But again, FBOs are businesses. Adding a tank and pump and meeting EPA regs and fire regs costs money. If the sales from that tank are 1/2 the sales from the 100 tank, how much more will they have to charge to make it a profit center?

I have burned 895 gallons in my airplane since early August last year (when I picked it up). So if G100UL is $1 a gallon more, that is $895. Compared to the price of the annual and insurance and hangar rental, it is not a large amount. Would I prefer it be $1 less? Yes, but it will not appreciably change the amount I fly.

BTW, the average price I paid for fuel last year was $6.21 per gallon.
 
NordicDave said:
Nearly all turbos required 100LL. Both Turbo-normalized and turbocharged.

The stats people quote keep saying the majority are twins. Lots of single engine Cessna turbos and Cirrus's in the fleet.
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And Pipers and Mooneys. :D
 
kyleb said:
Crop dusters are all flying turbine equipment these days. And much of the charter/corporate world has gone turbine.
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Not all. We had an ag operation run out of out field this last spring. 3 planes, 2 turbine, one with a radial. :)

It seems there is still a good bit of small part 135 in pistons. A friend just did an air taxi to get his parents to visit a relative for the last time. Seneca 2. Turbo, burns 100LL.
 
Todd82 said:
I personally know of an operation with 4 cabin class Cessnas that's burning up to 80,000 gallons a year. A few operations like that makes up for a ton of bugsmashers.
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Add Cape Air to the mix with their nearly 100 twins (Cessna 402, Tecnam P2012, and Islanders) providing daily air service.

What is the fuel burn for all of those R44's doing sight seeing flights?

I'll throw out another "I think":

I think it is the 1/3 of the fleet working day in and day out and not the 2/3 of the fleet that goes up every now and again for a burger/family vacation/currency/etc.
 
Pinecone said:
How much fuel did you burn over the last year?

Answered in post #11 but here goes again: ~2000 gallons 100LL

There is 94UL already and 91UL coming. But again, FBOs are businesses. Adding a tank and pump and meeting EPA regs and fire regs costs money. If the sales from that tank are 1/2 the sales from the 100 tank, how much more will they have to charge to make it a profit center?

Yes, I agree that the economics of having an additional a gas pump is an issue and stated so in the original post.

I have burned 895 gallons in my airplane since early August last year (when I picked it up). So if G100UL is $1 a gallon more, that is $895. Compared to the price of the annual and insurance and hangar rental, it is not a large amount. Would I prefer it be $1 less? Yes, but it will not appreciably change the amount I fly.

I would probably be pleasantly surprised if 100UL is priced ~ $1 more than 100LL. That would only mean an extra $2k/yr for me at current burn rate. I think the delta is going to be more than $1.

BTW, the average price I paid for fuel last year was $6.21 per gallon.
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Yes, lots more anecdotal I know of an operation that uses thousands……………

Where’s the real data from the study. It may be true. Facts and data.
 
GeorgeC said:
Close 2/3 of the airports, scrap the non-100UL fleet, hand out tax credits for the trouble, take credit for reduced emissions. #thereifixedit :popcorn:
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Or close 100% of the airports, scrap the entire fleet and take credit for more reduced emissions, plus completely eliminating air safety problems. If emissions are the worry, less is better, right?
 
Pinecone said:
There is 94UL already and 91UL coming. But again, FBOs are businesses. Adding a tank and pump and meeting EPA regs and fire regs costs money. If the sales from that tank are 1/2 the sales from the 100 tank, how much more will they have to charge to make it a profit center?
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Another angle to come at it is to ask how many gallons of 94UL or 91UL an FBO has to sell in order to cover the additional costs of carrying multiple types of avgas. There are more costs than the tangible items you mentioned. One thing that isn't being mentioned is the liability risk of misfueling. Another is transportation: An FBO that sells a truckload of one type of fuel pays for one truck while one that sells a half a truckload each of two kinds of fuel probably pays for two trucks.

Every FBO is going to end up making an independent decision about how to participate in the market. And a fleetwide statistic won't have the granularity that each FBO needs to make that decision. Who cares how many gallons of 100 octane avgas Cape Air burns if you aren't selling them gas? The real question is whether the quantity of lower-octane fuel you can sell locally will justify the headache and cost of being able to sell the lower-octane fuel alongside 100UL.

Given the barriers to entry, my guess is that most FBOs will go with the default option of simply selling the one type of fuel that everyone can use.
 
iamtheari said:
Another angle to come at it is to ask how many gallons of 94UL or 91UL an FBO has to sell in order to cover the additional costs of carrying multiple types of avgas. There are more costs than the tangible items you mentioned. One thing that isn't being mentioned is the liability risk of misfueling. Another is transportation: An FBO that sells a truckload of one type of fuel pays for one truck while one that sells a half a truckload each of two kinds of fuel probably pays for two trucks.

Every FBO is going to end up making an independent decision about how to participate in the market. And a fleetwide statistic won't have the granularity that each FBO needs to make that decision. Who cares how many gallons of 100 octane avgas Cape Air burns if you aren't selling them gas? The real question is whether the quantity of lower-octane fuel you can sell locally will justify the headache and cost of being able to sell the lower-octane fuel alongside 100UL.

Given the barriers to entry, my guess is that most FBOs will go with the default option of simply selling the one type of fuel that everyone can use.
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I agree, economically, with no grants involved, very few if any operations would add a second avgas pump. Even if they did, I wouldn’t think total avgas sales would change much.
 
focal_plane said:
I agree, economically, with no grants involved, very few if any operations would add a second avgas pump. Even if they did, I wouldn’t think total avgas sales would change much.
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I would imagine that any political will that exists to create and taxpayer-fund any kind of rollout of unleaded avgas will be too broad to get you the subsidized sub-100-octane gas you are hoping for. The grants we actually see will probably be “eliminate lead” rather than “offer multiple grades of gas.” Even if there is a grant program for the latter, FBOs will need to decide if the headaches are worth it. You could move the money ball all the way to the goal line with grant dollars and a lot of FBOs would still not want to carry it over the line.
 
iamtheari said:
I would imagine that any political will that exists to create and taxpayer-fund any kind of rollout of unleaded avgas will be too broad to get you the subsidized sub-100-octane gas you are hoping for. The grants we actually see will probably be “eliminate lead” rather than “offer multiple grades of gas.” Even if there is a grant program for the latter, FBOs will need to decide if the headaches are worth it. You could move the money ball all the way to the goal line with grant dollars and a lot of FBOs would still not want to carry it over the line.
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Yes, agree. I think where I was going with the grant thing was while we're waiting for the final 100UL to really roll out, deploy the now available 94UL to a number of airports. I'll flat earth WAG, 200 airports, $1M per to install portable fuel island plus some incentive for the operator like all political deals come with. For only $200M EPA takes bow for getting X% of the GA fleet off lead. Keep the 100LL flowing just like it does now and when 100UL comes, transition 100LL to 100UL. I'd love to get my plane off of lead for plug fouling, oil fouling etc. But 100LL does smell good, I wonder what 94UL smells like?

My sarcasm with the "only $200M" part is not well hidden but it pales by orders of magnitude compared to the truly wasteful crap that has been spent the last few years. Do I even remotely think this is possible? No.
 
RyanShort1 said:
Talking to my mechanic, a TON of airplanes fly less than 20 hours per year between annuals. I think the 80/20 rule is probably true there, too.
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Ryan, a TON of airplanes is about 1 or 1.5 planes.

I kid, I kid. : )
 
iamtheari said:
Another angle to come at it is to ask how many gallons of 94UL or 91UL an FBO has to sell in order to cover the additional costs of carrying multiple types of avgas. There are more costs than the tangible items you mentioned. One thing that isn't being mentioned is the liability risk of misfueling. Another is transportation: An FBO that sells a truckload of one type of fuel pays for one truck while one that sells a half a truckload each of two kinds of fuel probably pays for two trucks.
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A data point, from another board, member was just at an airport that pumped both 100LL and 94UL. The 94UL was $1 more per gallon than the 100LL.

Hmmmm
 
Pinecone said:
A data point, from another board, member was just at an airport that pumped both 100LL and 94UL. The 94UL was $1 more per gallon than the 100LL.

Hmmmm
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I know, I've seen advertised prices like that. Economy of scale? Infrastructure costs for additional pump built in?
 
Since there is a repeated demand for data here... could we generate most of this data with ADS-B? Perhaps make some general assumptions by type (172 = low compression, SR22 = high, etc) and suss out the hours being flown for each? It would be imperfect, since some types have both engine types represented, but it might be a start?
 
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