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FAA Wants All Aircraft Flying On Unleaded Fuel By 2018

Soulskill posted about a year ago | from the even-death-drones dept.

Transportation 366

coondoggie writes "The Federal Aviation Administration (FAA) this week put out a call to fuel producers to offer options that would safely let general aviation aircraft stop using leaded fuel by 2018. The FAA says there are approximately 167,000 aircraft in the United States and a total of 230,000 worldwide that rely on the current 100 octane, low lead fuel for safe operation. It is the only remaining transportation fuel in the United States that contains the addition of tetraethyl lead, a toxic substance, to create the very high octane levels needed for high-performance aircraft engines. Operations with inadequate octane can result in engine failures, the FAA noted."

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Thanks Slashdot. (4, Funny)

Capt.DrumkenBum (1173011) | about a year ago | (#43979453)

Now I know where I can get leaded gas for my old car. :)
Off to the airport. :)

Re:Thanks Slashdot. (3, Interesting)

Lehk228 (705449) | about a year ago | (#43979469)

if you get caught with avgas in your tank (it's dyed) you are in deep shit

Re:Thanks Slashdot. (1)

Anonymous Coward | about a year ago | (#43979499)

Name one person that has EVER had their tank checked, on a consumer vehicle.

My father buys off-road diesel (it's dyed), 1000 gallon at a time, for his farm and runs it in his pickups. Has been doing so for years.

Re:Thanks Slashdot. (5, Interesting)

LDAPMAN (930041) | about a year ago | (#43979627)

I've seen the Missouri State Police show up at a livestock auction and check every pickup as they leave. They were writing tickets by the bushel.

Re:Thanks Slashdot. (1)

PRMan (959735) | about a year ago | (#43979931)

I would refuse a search and call my lawyer.

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43980015)

I've seen the Missouri State Police show up at a livestock auction and check every pickup as they leave. They were writing tickets by the bushel.

Sorry, but... Is this a joke? That's how I took it, but it's modded only Informative or Interesting.

If it is true, then we have discovered the rare and elusive "Retro-Whoosh." That would be for me. Otherwise it's currently a hat trick of mod whooshes.

Re:Thanks Slashdot. (3, Interesting)

AK Marc (707885) | about a year ago | (#43980191)

Farmer diesel is dyed and (mostly) untaxed. Ticketing farmers for using untaxed tractor diesel on the road is common.

Someone else mentioned that avgas is similarly marked and similarly illegal to use on the road, though I know more than one street racer who fills up at the airport. And yes, it matters when you are trying to run turbos at higher compressions.

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43980051)

I've seen the Missouri State Police show up at a livestock auction and check every pickup as they leave. They were writing tickets by the bushel.

Misery is the only state that does that...

Re:Thanks Slashdot. (1)

Anonymous Coward | about a year ago | (#43979681)

Son, you done goofed, the cyberpolice have backtraced your IP and a tactical assault team is en route to your father's terrorist hideout.

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43979705)

It's true that nobody will pull you over and ask to see your tank. However, they WILL observe that you're buying quantities that do not match your flight records. From that they'll get a warrant and check your gas tank, and then they'll throw your ass in jail.

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43979893)

I buy unleaded avgas for my motorcycle and there's no paperwork.

Re:Thanks Slashdot. (5, Informative)

Anonymous Coward | about a year ago | (#43979897)

Bullshit. You clearly have *NO* clue how general aviation works. Anyone can go to the airport with a gas can and use the self serve station. Records are not kept. You do not have to own an aircraft to buy avgas. People at the airport here use it in the lawn mowers, the tugs, golf carts, chainsaws, etc. Hell, I use it in my 2-stroke RC car. I've bought 100LL all over the state on my personal credit card for aircraft I don't own.

Don't present as fact that which you have no clue about.

Re:Thanks Slashdot. (3, Funny)

Anonymous Coward | about a year ago | (#43980033)

Don't present as fact that which you have no clue about.

Welcome to Slashdot. Try the ramen.

Re:Thanks Slashdot. (2, Informative)

Anonymous Coward | about a year ago | (#43980203)

I have been checked 6 times in 12 years on my personal diesel. On my heavy equipment we average 1-2 checks per year per vehicle. This is in Alabama and Georgia.

Re:Thanks Slashdot. (1)

Capt.DrumkenBum (1173011) | about a year ago | (#43979501)

I was kidding. Hence the two :)

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43979503)

Yeah, those damn random gas tank contents tests are so common.

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43979813)

It's also really bad for catalytic converters (the lead plates onto them IIRC). Could be very expensive the next time you need an emissions test.

Re:Thanks Slashdot. (5, Informative)

Anonymous Coward | about a year ago | (#43979845)

Mix two different octanes of avgas together and the dyes disappear. It is a feature of avgas to alert pilots in case they mix octanes.

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43979519)

If you have such a car, you already know that there are additives and/or retrofits to make it run properly. Apparently avgas isn't taxed the same so you'd be breaking the law if you didn't put it in a plane.

Re:Thanks Slashdot. (0)

UneducatedSixpack (2829861) | about a year ago | (#43979599)

Yes, avgas is in $5-8 range when auto gas is below $4 a gallon. Apparently putting avgas in your car means that you are breaking laws of logic.Who in his/her right mind would want to fill up the car with gas that is more expensive and less available. Terrorist!

Re:Thanks Slashdot. (1)

postbigbang (761081) | about a year ago | (#43980041)

But when I put it in my motorcycle, whooopeeee! Goes like a rabbit!

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43980151)

If you have a noticeable increase in power, you need to get your engine fixed because knocking is the only reason to go with a higher octane rating.

Re:Thanks Slashdot. (1)

snowraver1 (1052510) | about a year ago | (#43980047)

100 octane. If I ever had a rally car (modified AWD turbo) avgas would be perfect!

Re:Thanks Slashdot. (1)

Deadstick (535032) | about a year ago | (#43980071)

Not much reason for using it in a car, but good reason for using it in lawnmowers, chainsaws and model airplanes: it leaves less stink on your hands and garage floor.

Why? (1)

Anonymous Coward | about a year ago | (#43979549)

Now I know where I can get leaded gas for my old car. :)

Off to the airport. :)

I never got that. What's so great about lead in gas?

And in the meantime, it puts lead in the environment (gasp! I'm concerned about the environment!) , the refiners fought tooth and nail for decades to keep it in auto gas, and it causes lower IQ in children and m,any many other health issues.

Is your shitty old car worth it? Your old out of date technology - 19th century technology - car worth it? That piece of shit machinery?

Why don't you sell the piece of shit to a moron and buy a Tesla?

Re:Why? (0)

Anonymous Coward | about a year ago | (#43979615)

Now I know where I can get leaded gas for my old car. :)

Off to the airport. :)

I never got that. What's so great about lead in gas?

Dr Forrester: "Oh, don't be such a baby, I've drank gallons of that stuff and it's only made me more powerful...and taller."

Re:Why? (2)

realilskater (76030) | about a year ago | (#43979669)

It was used extensively as an antiknock agent. It is still the best antiknock agent despite the enormous environmental impact of using it.
https://en.wikipedia.org/wiki/Tetraethyllead [wikipedia.org]

Re:Why? (1)

postbigbang (761081) | about a year ago | (#43980059)

But these days, the O2 sensor cuts pre-ignition to nothing, even the ugly ancient late '80s and early '90s "computers" (actually just ugly logic boards) for most cars and trucks built after the early 1970s.

In an aircraft, engines and conditions are vastly different. Many are very simple, and will require costly adaptation to use lower octane fuel, and so fuel additives and MOHs will rule the day.

Is it beneficial? Ultimately, yes, IMHO.

Re:Why? (4, Informative)

sd4f (1891894) | about a year ago | (#43979783)

the lead in petrol had a few benefits, it raised the octane number, allowing the engines to have higher compression ratios, providing better thermal efficiency of the engine. Also in the era when engines where made from detroit wonder metal (cast iron) certain parts were lubricated by the lead, so they could remain as cast iron, such as valve seats, whereas unleaded fuel has required hardened valve seats to be inserted.

Re:Why? (0)

Anonymous Coward | about a year ago | (#43979865)

I am the moron he sold it to. Quit labeling me!

Re:Why? (0)

Anonymous Coward | about a year ago | (#43980073)

Because he's ingested too much lead to have any brain cells left...

low lead is misleading (1)

Anonymous Coward | about a year ago | (#43979723)

100LL avgas has over 20 times the tetra-ethyl lead compared to leaded automobile fuel. And that was after the TEL in 100LL was reduced by a factor of 2.

Re:Thanks Slashdot. (0)

Anonymous Coward | about a year ago | (#43979855)

you can also get lead substitute in the auto parts store for classic cars. You put it in your tank every fill up.

Re:Thanks Slashdot. (1)

LWATCDR (28044) | about a year ago | (#43980129)

No you really do not. Even 100LL has a lot more lead than you want to put in a car engine.

mostly some small private planes left (4, Informative)

Trepidity (597) | about a year ago | (#43979475)

It's piston-engine stuff like Cessnas that make up the remaining leaded avgas users, and even there, only the subset of engines that require the 100-octane avgas. Both newer and some older stuff can use 91-octane stuff that's now unleaded.

Re:mostly some small private planes left (1)

Anonymous Coward | about a year ago | (#43979581)

There are a lot of piston aircraft that require leaded fuel, not just Cessna's. There are Pipers. Beechcraft, Cirrus and many others.
They also cannot tolerate ethynol or blended seasonal fuels. The expense for facilities that sell fuel to aircraft to add another fuel farm is not trivial either.

I hope they can find a solution by 2018 but it is not going to be easy

Re: mostly some small private planes left (-1, Troll)

alen (225700) | about a year ago | (#43979641)

So?

If you must fly for fun then no reason why you should not pay the environmental costs

Re: mostly some small private planes left (3, Informative)

MechaStreisand (585905) | about a year ago | (#43979913)

There AREN'T ANY, you fuckwit. There are so few general aviation aircraft flying that the lead in their fuel makes no measurable environmental impact at ALL.

Re: mostly some small private planes left (1)

Gr8Apes (679165) | about a year ago | (#43980093)

And why is that? Because of the regulations that have pushed that fuel out of favor. Tax it more, it should be undesirable. And, IIRC correctly, all those older engines can be rebuilt to handle non-leaded gas. Yeah, it won't be "authentic" anymore, but it wouldn't be anyways since if you use it, the only reason I can see why you'd be pissed at the increased cost, you'll be making or buying non-authentic replacement parts anyways.

Re: mostly some small private planes left (-1)

Anonymous Coward | about a year ago | (#43980107)

Still amounts to about 500,000 gallons per day, which is about 1000 kg of lead.

Re: mostly some small private planes left (0)

Anonymous Coward | about a year ago | (#43980029)

This is exactly how they should handle the transition. Simply inform everyone that, as of 2018, there will be a significant (multi-dollar/gallon) tax placed on leaded fuel. Companies are free to anticipate the change or not and pay the consequences. No need for a government mandate against the fuel. And if people want to continue to fly with it, the revenues from the tax can probably offset the environmental damage.

Re:mostly some small private planes left (1)

ttucker (2884057) | about a year ago | (#43980189)

It is ethanol.

Re:mostly some small private planes left (0)

Anonymous Coward | about a year ago | (#43979659)

It's more than just a "small number" or a "subset".

There are roughly 155,000 piston planes in the general aviation fleet.
The vast majority of those require 100LL avgas.

Also, the vast majority of the new GA aircraft that are being produced still require 100LL avgas as well. The new Cessna 182 that can use Jet-A and the light sports and experimentals that can run on 91 octane unleaded are essentially in the noise in terms of total number of aircraft being produced.

Re:mostly some small private planes left (1)

Trepidity (597) | about a year ago | (#43979731)

About 1/3 of current GA piston planes can use an unleaded fuel. I would guess that number would increase rapidly if there were a phase-out period where 100LL were taxed to make it significantly more expensive.

Re:mostly some small private planes left (2)

tlhIngan (30335) | about a year ago | (#43979677)

It's piston-engine stuff like Cessnas that make up the remaining leaded avgas users, and even there, only the subset of engines that require the 100-octane avgas. Both newer and some older stuff can use 91-octane stuff that's now unleaded.

There are however a LOT of older planes around that require leaded - plenty of them dating to when liability lawsuits resulted in halted production sometime in 1986, and plenty more during the boom period of 1997 (when production resumed thanks to Clinton's limited product liability act) and 2008. Newer ones generally are certified for low octane, but there's plenty of planes flying about that aren't.

In fact, the industry has seen this coming and actually has done formal research into research and testing leaded avgas alternatives - an association formed between associations representing pilots, manufacturers, the FAA and others.

The basic goal is to come up with an equivalent to 100LL that can be used transparently, because certifying all the old aircraft for new fuels is finicky, at best, and an boondoggle of costs at worst. Having an unleaded 100LL alternative that is equivalent means all those old engines don't require a lick of work being done to them.

As for unleaded "mogas" (car gas), it turns out that a lot of them are now out of reach because biogas is incompatible - I think they can handle 5% ethanol, but newer ones have higher percentages and are actually not certified for flight use.

Re:mostly some small private planes left (1)

CastrTroy (595695) | about a year ago | (#43980133)

The big questions are, how many miles are these planes flying, and how much actual fuel are they using. Sure there's a lot of planes out there that use this kind of fuel, but how often do they get used? Are they mostly pleasure type aircraft that maybe fly a few hours a week? Does it really create a huge problem in the environment? Only stating the number of aircraft is useless if the planes are never flown, or only account for a miniscule amount of pollution generated from air travel.

Re:mostly some small private planes left (1)

LWATCDR (28044) | about a year ago | (#43980079)

Actually the new unleaded AVgas is supposed to work in all of them.

Re:mostly some small private planes left (1)

stox (131684) | about a year ago | (#43980135)

Does the new unleaded AVGas lubricate the valve seats like lead does? That was the issue with old cars, putting in new valves and valve seats would solve the problem.

Octane Levels? (0)

Anonymous Coward | about a year ago | (#43979479)

Octane rating... RON, etc...

Who's going to pay for it? (4, Insightful)

Anonymous Coward | about a year ago | (#43979489)

So in 6 years, the FAA expects 167,000 aircraft owners to swap the engines in their aircraft for an unleaded engine? In 6 years companies are supposed to develop an unleaded engine that will fit in every type of small prop aircraft currently flying? Yeah, not happening.

And as a small single engine plane owner myself, I'll be damned if the government forces me to spend 30K on swapping out a new engine, then more on inspections and re-certification of the aircraft.

Re:Who's going to pay for it? (1)

Sperbels (1008585) | about a year ago | (#43979551)

I'll be damned if the government forces me to spend 30K on swapping out a new engine, then more on inspections and re-certification of the aircraft.

I'm not questioning that figure (because I know it's true) but why do airplane engines cost so friggin much?

Re:Who's going to pay for it? (0)

Anonymous Coward | about a year ago | (#43979579)

I'm not questioning that figure (because I know it's true) but why do airplane engines cost so friggin much?

Certification, niche market, insurance all the way down the supply chain, etc.

Re:Who's going to pay for it? (4, Insightful)

Kaenneth (82978) | about a year ago | (#43979643)

I'll be damned if the government forces me to spend 30K on swapping out a new engine, then more on inspections and re-certification of the aircraft.

I'm not questioning that figure (because I know it's true) but why do airplane engines cost so friggin much?

Compare to the price of mid-air failure.

Re:Who's going to pay for it? (0)

Anonymous Coward | about a year ago | (#43979667)

An Aircraft isn't toddling down the Interstate when a comforting shoulder can usually be found to park your automobile with a sputtering engine. An Aircraft can crash--hence, higher standards of performance and safety. These higher standards cost a lots of money. (These standards also effect Commercial Aviation. If you have ever taken a plane flight, you should be greatly thankful for these standards which saved your life.)

Re:Who's going to pay for it? (1)

LWATCDR (28044) | about a year ago | (#43980067)

Lawyers and small market.
Liability is just through the roof. One problem is that no one wants to speak ill of the dead. You never hear about a bad private pilot crashing because no one wants to heap blame on the dead and their family. The end result is that even if the it is the pilots fault the family will often win the lawsuit.
Second the small number of aircraft built. More Cessna 172 were built than any other light aircraft with over 43,000 made. The problem is that it has been in production since 1955! That averages out to less than 800 per year. They probably build more Roll Royces per year than light aircraft. Now homebuilts are a different matter but they often do not use certified aircraft engines.

Re:Who's going to pay for it? (5, Informative)

joe_frisch (1366229) | about a year ago | (#43980095)

They are also much lower volume production than car engines. The designs are different enough that it isn't easy to just substitute automobile engines for aircraft use. Its been tried, and has worked in some cases, but not many.

Basically aircraft engines turn slowly (usually 2700 rpm max) because the propeller tips need to stay subsonic. Gear boxes are very heavy because of the large moment of inertia of the propellers and haven't worked very well in most installations. The low engine speed means that it needs very large displacement (9 liters is not uncommon) to get the required power. Light weight / high airflow give you air cooled, aluminum-finned engines. The aircraft engines are actually very efficient at their normal operating point. Part of this is due to the high compression allowed by high octane fuel.

Re:Who's going to pay for it? (1)

tompaulco (629533) | about a year ago | (#43979555)

You also forgot to mention (though you likely know) that getting a STC (Supplemental Type Certificate) for an Unleaded Gasoline engine in the hundreds of models that are still using 100LL is going to take many millions of dollars and years of testing and paperwork to push through the certifying authority, which also happens to be the authority trying to force the issue.

Call is for new fuels for existing engines (5, Informative)

DragonWriter (970822) | about a year ago | (#43979679)

You also forgot to mention (though you likely know) that getting a STC (Supplemental Type Certificate) for an Unleaded Gasoline engine in the hundreds of models that are still using 100LL is going to take many millions of dollars and years of testing and paperwork to push through the certifying authority, which also happens to be the authority trying to force the issue.

Yeah, its a good thing that the FAA isn't talking about new engines at all, but instead calling on fuel producers to come up with replacement fuels that will work in current engines. Which is stated not only in TFA, which I can understand is a huge bother to read before complaining, but in the first sentence of the summary, as well.

Re:Who's going to pay for it? (1)

Anonymous Coward | about a year ago | (#43979563)

Yes.

Heavy metal poisoning/pollution isn't an issue be taken lightly. 6 years is being generous. Those planes should already be grounded.

Re:Who's going to pay for it? (5, Insightful)

Anonymous Coward | about a year ago | (#43979585)

So, you expect everybody else to breathe in your brain damaging exhaust to save you some bucks.

Tell you what, why don't you route your exhaust through the plane cabin and filter it with your lungs first.

Re:Who's going to pay for it? (0)

Anonymous Coward | about a year ago | (#43980063)

You do that, so why can't he?

Re:Who's going to pay for it? (4, Insightful)

fuzzyfuzzyfungus (1223518) | about a year ago | (#43979623)

As the owner/operator of a complex network of around 100 billion neurons, along with support infrastructure, I'm not entirely sympathetic to your desire to continue emitting lead. Nothing personal.

Re:Who's going to pay for it? (2)

ColdWetDog (752185) | about a year ago | (#43979757)

You're sure you own all those neurons? Have you read the EULA recently?

Re:Who's going to pay for it? (2)

fahrbot-bot (874524) | about a year ago | (#43979773)

As the owner/operator of a complex network of around 100 billion neurons, along with support infrastructure, I'm not entirely sympathetic to your desire to continue emitting lead. Nothing personal.

You're on /. so it can't be *that* complex :-)

Re:Who's going to pay for it? (2)

fuzzyfuzzyfungus (1223518) | about a year ago | (#43979837)

Oh, it's complex alright, it's just a question of how much of the complexity is unbelievably shoddy legacy code held together with little more than axons and optimism, and how much of that complexity can actually be deployed to some useful end.

Either way, I can hardly afford to have it work yet worse than it works now...

Re:Who's going to pay for it? (0)

Anonymous Coward | about a year ago | (#43980055)

...And I suppose you think that MTBE is better? If the engine is operated properly, the amount of lead emitted is very minimal. Meanwhile, though TEL was an air pollutant, MTBE is water soluble. Many are drinking it now and we're not sure just what long term effects it will have.

We need to be very careful, whatever octane boosting agent is used, that it doesn't become an even more dangerous pollutant following combustion.

Re:Who's going to pay for it? (2)

adolf (21054) | about a year ago | (#43980091)

...And I suppose you think that MTBE is better? If the engine is operated properly, the amount of lead emitted is very minimal. Meanwhile, though TEL was an air pollutant, MTBE is water soluble. Many are drinking it now and we're not sure just what long term effects it will have.

MTBE is an oxygenator added to cause engines to run leaner by government mandate. TEL improves octane rating.

Just because thery're both fuel additives, does not mean that they are not: Two. Completely. Different. Things.

Re:Who's going to pay for it? (1)

LWATCDR (28044) | about a year ago | (#43980109)

Honestly there are so few of them that it is not really a danger. Old fishing weights, lead figures, and old TVs are much more dangerous. The EAA was working with the FAA to produce a compatible avgas that is lead free so it is probably going to be a win win. It should even reduce the cost of avgas since leaded avgas can not be put in pipelines and has to be trucked or shipped by barge.

Fuel producers != Aircraft owners (3, Informative)

DragonWriter (970822) | about a year ago | (#43979645)

So in 6 years, the FAA expects 167,000 aircraft owners to swap the engines in their aircraft for an unleaded engine?

No, and you can tell this from the first line in TFS: "The Federal Aviation Administration (FAA) this week put out a call to fuel producers to offer options that would safely let general aviation aircraft stop using leaded fuel by 2018."

They want fuel producers to offer options that will meet the need of aircraft that are currently dependent on leaded fuel to operate properly without lead.

And as a small single engine plane owner myself, I'll be damned if the government forces me to spend 30K on swapping out a new engine

I get that its a lot to ask you buy a new engine, or even to RTFA, but could you at least bother to read the first sentence of the summary before exploding with outrage next time?

Re:Who's going to pay for it? (0)

Anonymous Coward | about a year ago | (#43979653)

I'll be damned if

We're already all damned by the lead you're dropping on us.

Re:Who's going to pay for it? (0)

Anonymous Coward | about a year ago | (#43979713)

The whole point of this program is to develop a fuel that requires minimum modification to existing aircraft engines certified for 100LL, since nobody has been able to develop a drop-in substitute. If the FAA wanted to mandate complete engine redesigns, it would make much more sense to design engines for existing fuels (Jet A, auto gas)

Re:Who's going to pay for it? (1)

esampson (223745) | about a year ago | (#43979745)

The government isn't asking you to do anything. It's asking the fuel companies to come up with a 100 octane fuel that will run in your older engine that doesn't contain lead.

Now if you want to get indignant about the poor, put upon oil companies, have at it.

Re:Who's going to pay for it? (0)

Anonymous Coward | about a year ago | (#43980165)

Bah. I'm sure someone once made that same arguement about requiring unleaded fuel for cars. And I guarantee there were many, many, more cars on the road back then than there are old aircraft flying around now.

And it'll be handled the same way. There will be a transition period when both leaded and unleaded fuel will be available. During this transition, new engines will be required to use unleaded. After the transition period, leaded fuel will be removed from the market. And anyone who insists on flying one of those decrepit old beaters that still "require" leaded gas will do what people who insist on *driving* decrepit old beaters do: They'll pour an additive in with each tank of gas to replace the lead.

6-Cyl will be an issue (0)

Anonymous Coward | about a year ago | (#43979531)

The people that own 6-cylinder engines are going to have the most issue finding a replacement. Most 4-cylinder engine will take auto fuel, but could need new fuel pumps/carburator parts that are able to survive in an ethanol world. The 6's just cannot make the same HP on the auto fuel they can on 100LL.

Re:6-Cyl will be an issue (1)

Nimey (114278) | about a year ago | (#43979673)

Why, do 6-cyl aero engines typically have higher compression?

Re:6-Cyl will be an issue (1)

ColdWetDog (752185) | about a year ago | (#43979769)

Higher output per weight. Aircraft manufacturers and operators, especially for smaller planes, obsess about weight.

Example: Rotax 912 (1)

sanchom (1681398) | about a year ago | (#43979537)

The Rotax 912 and Rotax 912s found in Diamond's DA20-A1 and DA20-100 are certified 91 octane unleaded fuel.

Re:Example: Rotax 912 (1)

sanchom (1681398) | about a year ago | (#43979559)

That is, certified to use 91 octane unleaded fuel.

Re:Example: Rotax 912 (1)

bunyip (17018) | about a year ago | (#43979593)

Yes, these engines are fine on auto fuel, known as MOGAS. The thing we have to be careful about is the ethanol they add to unleaded gas, so we go to a lot of trouble to avoid it.. Alcohol in the fuel can lead to corrosion. And to high food prices, but that's a whole 'nuther story...

Problem is not the technology but antique planes (5, Informative)

quarterbuck (1268694) | about a year ago | (#43979597)

The issue is not with airlines (which use Jet fuel) or with Commercial operations (mostly using newer engines). It is with the flight schools and other General Aviation users.

The problem with leaded fuels is not really that technology to use unleaded is not available, but that most of the General Aviation Fleet that is flying is older technology. Majority of the GA fleet are from 1970's or 80's when Cessna and Piper dominated the market.
Then came lawsuits (frivolous and otherwise) and most of the manufacturers filed for bankruptcy. The airplanes from the 90s tend to be mostly homebuilt. Post 2000s a lot of the companies came back from bankruptcy and started making airplanes again. The only problem is that a new Piper costs about $200K while a perfectly usable 1970s Piper with overhauled engine and modern avionics is only about $30K. Airplanes last a lot longer than cars if regularly maintained. So most flying crafts tend to be old.
So these older planes which were designed for leaded gas get recertified for low lead gas, but can never use unleaded.
Newer aircrafts tend to do two things,
1) Run on motor gas (mostly involves certifying for unleaded gasoline) . This has the nice side effect that the gas tends to be about 30% cheaper.
2) Run on Diesel/Jet Fuel / Kerosine - In this case it sidesteps the entire lead problem and also avoids using spark plugs (depending on the design). Fuel availability is a lot better, though not always cheaper.
One easy solution is to make unleaded mandatory for any Light Sport aircraft (which tend to be the newer airplanes built) and to increase a fee imposed while overhauling older engines (which get done every 1000 hours).
That said, this move would permanently ground the WW2 display fleet that is currently flyable and a bunch of old Piper Cubs and Ercoupes. But they are all pre-ww2, so not a big loss I guess.

Re:Problem is not the technology but antique plane (1)

Nimey (114278) | about a year ago | (#43979697)

I expect the authorities would make exceptions for warbirds... I'd hope so, at least.

Re:Problem is not the technology but antique plane (1)

quarterbuck (1268694) | about a year ago | (#43979815)

Yes sure they can make an exception, but where would you then get the gas from ? You probably have to mix in lead directly in at the carb or something...

Re:Problem is not the technology but antique plane (1)

caseih (160668) | about a year ago | (#43979939)

When Canada phased out leaded gas some years ago, you could buy an additive for older engines that you just poured in the gas tank. So I imagine that something similar could be done for exempt aircraft. Mixing in a tank first would probably be much cheaper than modifying a carb and much safer.

Re:Problem is not the technology but antique plane (3, Funny)

He Who Has No Name (768306) | about a year ago | (#43979835)

They probably won't.

The FAA has a deep and seething contempt towards former military aircraft in private hands... above and beyond their general malicious contempt of aircraft in general in private hands.

Re:Problem is not the technology but antique plane (1)

drinkypoo (153816) | about a year ago | (#43979729)

Airplanes last a lot longer than cars if regularly maintained

That might be true, because so many of them are mostly Aluminum, and Aluminum oxide protects Aluminum in precisely the way that Iron Oxide doesn't protect Iron. But it might not be, because who properly maintains cars? Washing the undercarriage regularly and so on? Pretty close to nobody.

this move would permanently ground the WW2 display fleet that is currently flyable and a bunch of old Piper Cubs and Ercoupes. But they are all pre-ww2, so not a big loss I guess.

Isn't it possible to produce conversion parts?

Re:Problem is not the technology but antique plane (0)

Anonymous Coward | about a year ago | (#43979811)

> One easy solution is to make unleaded mandatory for any Light Sport aircraft (which tend to be the newer airplanes built)

I don't have industry figures but there are plenty of non-light-sport piston airplanes being produced these days too.. Cirrus, Diamond, and the remaining old guard companies like Cessna are still around and are not primarily in the light sport business. They're also producing higher performance aircraft that require engines that have classically run on 100LL.

Meanwhile, the overwhelming majority of light sport aircraft (>90%) use Rotax engines which already can run on unleaded. A bigger issue for those planes is that 91 octane unleaded is almost universally unavailable at airfields, so if you are unable to haul your own gas to the plane you are back to burning leaded gas.

Re:Problem is not the technology but antique plane (0)

Anonymous Coward | about a year ago | (#43979949)

> One easy solution is to make unleaded mandatory for any Light Sport aircraft

Bad idea, and totally not necessary. The majority of leaded avgas users are actually company planes, not Light Sport. With LS, we already can and do use unleaded pretty much as we please, except for one thing -- ethanol. Ethanol mixes with water and the vapor pressure is different. Airplanes go up and down in altitude which greatly affects vapor pressure and temperature. You can get vapor lock and frozen fuel lines. The way around the ethanol problem is pressurized fuel systems, but that's not anywhere near as easy on all light sport aircraft as it is in automobiles. The PROBLEM is that the EPA lets the corn industry run them around by saying that requiring fuel to be labelled as containing ethanol is discriminatory. So we don't know which fuels have ethanol in them at the pump! The simplest solution right now would be for the EPA to mandate that one grade of automotive fuel shall always be ethanol free and the problem would be pretty much solved for Light Sport. Simple stroke of the pen. But they won't do it for some unknown reason, most likely related to greed.

Re:Problem is not the technology but antique plane (1)

kybur (1002682) | about a year ago | (#43980027)

Plenty of old engines can get a supplemental type certificate (STC) to run on motor gas. The problem is that gasoline is hard to find these days. In Massachusetts, there is not a single service station, on or off airport that sells gasoline. They all sell gasohol, which is gasoline with 10% ethanol (or in rare cases MTBE) added. Every STC that I've seen specifically excludes fuel with alchohol additives. One reason being alcohol's affinity for water. You need to be able to separate out the water from the fuel and you can't do it if alchol is present. At high altitudes (cold temperatures), water, or hydrous ethanol can become slushy, clogging fuel lines and filters. Needless to say, that's very bad. Cubs and Ercoupes probably can run on motor gas (without alcohol), because they do not have high performance / high compression engines, and were never restricted to at least 100 octane fuel.

Re:Problem is not the technology but antique plane (0)

Anonymous Coward | about a year ago | (#43980139)

Actually, many of the old Piper Cubs and Ercoupes were designed to run on 80 octane (red) aviation fuel. They can run on ethanol-free MOGAS with no problems. The engines such as the TSIO-470 from the 1960s and 70s are the ones to be afraid of. Those will detonate very easily, even on 100LL.

Another minor correction: most engines today have recommended TBO times between 1400 and 2000 hours of service. If you do 14CFR91 operations only, you can go past TBO times legally. However, I would do so cautiously with regular oil analysis and frequent use of the aircraft.

Lead toxicity (1)

oldsaint (736226) | about a year ago | (#43979719)

The removal of lead from automotive gasoline in 1976 brought about a very significant reduction in airborne lead, for which there was a risk of exposure by inhalation. There is little to no need for additional reduction to mitigate that risk. The only remaining serious risk of lead exposure is by ingestion of lead paint chips by children living in old houses. The FAA will need to be very careful not to increase the risk of aircraft engine failure beyond any possible mitigation of a minuscule inhalation exposure.

Re:Lead toxicity (0)

Anonymous Coward | about a year ago | (#43979927)

I didn't even know aircraft fuel still had lead in it. Turns out the chemtrail conspiracy nuts were not entirely wrong after all then.

Re:Lead toxicity (0)

Anonymous Coward | about a year ago | (#43980115)

Chemtrail nuts are still wrong. Jet fuel is unleaded.

Re:Lead toxicity (1)

Anonymous Coward | about a year ago | (#43980181)

Working practically next door to a small airport with relatively high traffic (as dot the SF Bay Area) I would disagree. Recent studies are showing there is no safe dosage of lead.

Lead paint is also a big concern and for even a bigger reason: New parents tend to move into a place more suited for children, and often the first thing on their list is to renovate their new house... thus exposing their kids to lead which would have been safely sequestered under several layers of modern paint.

In other news ... (1)

Kittenman (971447) | about a year ago | (#43979743)

"Kittenman wants to win huge amount on lottery by 2018"

Yawn. We need less speculation and wishes in slashdot, more hard data. Well, that's my opinion.

There are alternatives to retrofitting (2, Informative)

Anonymous Coward | about a year ago | (#43979777)

I used to do analytical work on fuel certification in a refinery, and while I didn't measure the "octane number", I understand what it means.

The number 100 refers to the performance of pure isooctane (2,2,4-trimethylpentane) as a fuel - isooctane is simply a reference for the "100" rating. Fuels are assigned a higher number when they are tested and shown to have a lower tendency to undergo premature ignition in an internal combustion engine (this phenomenon is known as knocking). Such premature ignition occurs when fuel and oxidant in a hot engine cylinder are compressed as part of normal operation of the engine and is more probable when the fuel has a lower activation energy for combustion and fewer radical scavengers are present in the fuel mixture.

Other compounds (aromatics like toluene and xylene isomers, tetraethyllead, methylcyclopentadienyl manganese tricarbonyl ) also enhance the "octane" number. The latter (MMT) is routinely blended into automotive gasoline in Canada despite being a known heavy metal/neurotoxin with likely worse long-term effects than tetraethyl lead (...!).

Among these various options, the straight hydrocarbons are far preferable and can be used without modification of engines to accomodate the exclusion of lead.

The only reason the heavy metals are used is to reduce the cost of filling one's tank.

Re:There are alternatives to retrofitting (1)

ebno-10db (1459097) | about a year ago | (#43979851)

The only reason the heavy metals are used is to reduce the cost of filling one's tank.

From a backwards compatibility viewpoint, what about exhaust valves? From http://en.wikipedia.org/wiki/Leaded_gasoline#A_valve_wear_preventive [wikipedia.org]

Tetraethyl lead works as a buffer against microwelds forming between the hot exhaust valves and their seats.[3] Once these valves reopen, the microwelds pull apart and leave the valves with a rough surface that would abrade the seats, leading to valve recession. When lead began to be phased out of motor fuel, the automotive industry began specifying hardened valve seats and upgraded exhaust valve materials to prevent valve recession without lead.

Not a big deal for new designs, but with cars anyway it meant it was a bad idea to use unleaded gas in old models that weren't designed for it.

Re:There are alternatives to retrofitting (0)

Anonymous Coward | about a year ago | (#43980101)

This is *exactly* why switching away from 100LL is problematic. There are plenty of other ways to increase octane, but not to prevent valve seat wear in these older engines.

Bad Bad Bad (0)

Anonymous Coward | about a year ago | (#43979787)

I have read that such a requirement is going to be devastatingly bad for the current small plane industry. Most plane engines are built around leaded gas and cannot take anything but. Just another bright idea by our government that will hugely cost and destroy an industry.

Re:Bad Bad Bad (1)

Spy Handler (822350) | about a year ago | (#43979877)

Just another bright idea by our government that will hugely cost and destroy an industry.

General aviation is mostly the 1% ... our illustrious leader couldn't care less about them. Occupy General Aviation now!

Why do they even need leaded fuel still? (0)

Anonymous Coward | about a year ago | (#43979935)

I thought we were long past that!

If it is just an octane issue, then surely super unleaded and things like BP Ultimate and Shell V-Power would be fine?

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