E10,True or False.

[farri]

Found this on the net.

 

 

Ethanol and Rotax engines What's its effect?. Phillip Lockwood

 

Question: What problems if any are associated with the use of E10 fuel in Rotax aircraft engines?

 

Answer: Fresh autogas without alcohol a is the preferred fuel for all Rotax aircraft engines. However, in many parts of the United States and Canada, gasoline is blended with 10-percent ethanol to produce a product referred to as E10 fuel. Ethanol is an alcohol commonly made from corn or sugar cane. The added ethanol in E10 fuel offers advantages and disadvantages.

 

The Advantages:

 

Ethanol acts as an oxygenate, which means it adds oxygen to the gasoline. Ethanol is 35 percent oxygen by weight and replaces methyl tertiary butyl ether (MTBE) to help the fuel burn more completely and cleanly, thus reducing smog-forming and ozone-eating emissions. Adding 10 percent ethanol increases a fuel's octane rating by two or three points. Widespread use of E10 fuels will significantly reduce our dependence on foreign oil. Because alcohol absorbs water, gasoline with added alcohol should help keep fuel systems free of water, so water should not be present when sumping the tanks and/or gascolator on an aircraft filled with E10 or any Officially, Rotax has approved the use of fuel with up to 5 percent alcohol content. Other than a slight increase in the exhaust gas temperatures (EGT), the engines seem to work fine operating on blends with up to 10 percent ethanol. Most autogas produced today has at least some alcohol mixed in to help reduce unwanted auto emissions.

 

The Disadvantages:

 

When using E10 or any fuel with alcohol in any aircraft application, potential problems exist. The greater the percentage of ethanol, the greater the chance you will experience problems, which can include the following:

 

Damage to rubber gaskets and composite fuel tanks. E10 fuel is not as friendly as avgas or pure gasoline to these components. The aircraft fuel system must be compatible with E10 fuels to avoid this damage. Corrosion problems with metal tanks, electric fuel pumps, and other fuel system components. Ethanol, or any type of alcohol, readily absorbs water. It may even absorb signiffcant amounts of water from the atmosphere in humid conditions. If too much water is absorbed, phase separation can occur, which results in the water and ethanol combining and falling to the bottom of the fuel tank. This combined water and ethanol can be quite corrosive to metal tanks and fuel system components, especially if the water and alcohol are allowed to remain in the bottom of the fuel tank for some length of time. If properly equipped with fuel tank sump drains, the water/ethanol combination can be drained off leaving only the gasoline, but it will have a slightly reduced octane level--down by 2 to 3 points using the antiknock index (AKI) rating method. (The Rotax 912ULS, the turbocharged 914, and the two-stroke 618 engine all require 91 octane fuel using the AKI rating method. The 912UL (81-hp) and the two-stroke 447,503, and 582 engines will run on 87 octane.)

 

Because of ethanol's propensity to absorb water:

 

Frank.

 

 

[Jack Tyler]

For those of us who do long distance sailing - and so carry a jugged supply of gasoline for the dink's outboard, the dink being the 'family car' upon arrival - ethanol-laced gas is known to lose more of its punch sooner, providing disappointing performance from the outboard. Not long ago, a Highlander builder and good buddy showed me an E10 summary that suggested one shouldn't store E10 fuel for more than 2 weeks if needing the performance from the gas they thought they were buying. I couldn't help but think, given all this, about aircraft owners who for a mix of reasons fuel the plane and then are unable to fly it for a period of time: travel commitments, illness, inhospitable seasonal weather and so forth. Where I'm located at the moment - St. Pete, FL USA - plane owners sometimes visit the local harbor fuel station to fill their jugs, since marinas are (for now...) exempt from the E10 mandate.

 

I would think E10 fuel would be a special concern for those owners out in our western states, where high density altitude is a given on almost every flight.

 

Jack

 

 

[Guest Maj Millard]

I would go with that info Frank....sorry won't put E10 in my aeroplane............Maj...

 

 

[Guest ozzie]

tried using stale 2 month old E10 in lawn mower and it would not start. changed the fuel and away it went. Remember the previous disscussions on ethanol fuels? that it is your fuel system not the rotax engine that will cause you the most problems.

 

http://www.rotaxservice.com/rotax_tips/rotax_feed2.htm

 

interesting read

 

 

[Jack Tyler]

...although being addressed to the care & feeding of 2-stroke engines.

 

Jack

 

 

[Vev]

In my view, ethanol fuels is really all about meeting political agendas ... I think there are very few positive characteristics about ethanol and wont use it in any of my toys.

 

I say ... Alcohol is best mixed with drinks and not mixed with flying.

 

Cheers

 

Vev

 

 

[Guest ozzie]

Yes in NSW it came down to Premier Bob Carr and his giving a contract and grant to a mate to expand his ethanol plant. Macbank is in on it as well.

 

 

[Guest davidh10]

Rotax approve Mogas with Ethanol mixes up to and including E10 in Rotax 912 / 914 engines. Mixes above E10 are untested. Please refer to SI-912-016 R3 and SI-914-019 R3 "Selection of Suitable Operating Fluids" respectively from the Rotax-Owner web site. {They are actually combined in one 13 page document.}

 

It should be noted that this applies only to the engine and not to the other fuel system components, so you still need a statement of compatibility for the aircraft as a whole.

 

My aircraft is teetotal:)

 

 

[winton]

winton

 

alcohol and fibreglass dont mix.

 

be aware!

 

 

[pudestcon]

This might be out of left field and a touch naive, but is there anyway to 'distil' the ethanol out of the mix and end up with a useable fuel?

 

Pud

 

 

[Guest ozzie]

You can by adding water to absorb the ethanol and then seperate the remaining fuel. BUT you will end up with a fuel of lower octane. You will have to add a octane booster to get a decent bang from it.

 

 

[Vev]

Hi Pud,

 

Yes you can strip ethanol out out of fuels ... however you will deplete the octane of the fuel which will cause significant performance problems (detonation etc), not to mention you will end up with a waste disposal issue and an economic loss of 10% of your purchase price. Apart from all of that, it's also dangerous to mess around with such volatile products, which is never a good idea.

 

I think one is better off avoiding using ethanol blend fuels whenever possible ... if you have a choice, use unblended fresh fuels every time.

 

Cheers

 

Vev

 

 

[Sloper]

Maybe l am going about this wrong but l intend to build my fuel system ethonhol freindley and not worry to the same extent of others about blends.

 

l see a small amount of ethonhol has a bonus, higher octane and it will take any small amounts of water out of the fuel system saferly.

 

But l plan to use BP Ultimate, no ethonhol.

 

regards Bruce

 

 

[Guest ozzie]

I've been following the ethanol debate for some time now and have come to the same conclusion that if building a new aircraft or any petrol powered device that the fuel system would have to be able to handle ethanol in any amount. Even if i had no intention of running it on ethanol blends. Just about all new engines are capable of handleing the stuff. Even so chances of getting caught by mislabled product or dodgy fuel suppliers i consider to be high. Having a fuel system that can handle it would save a few headaches. Especially if the straight stuff dissapears over the next decade.