Removing Ethanol from Gas?

On Wed, 9 Aug 2006 10:12:00 -0700, "Al"
wrote:
On that hot day at high altitude, over an obstacle, which takeoff
performance chart do I use?

The one that says, "stay on the ground and have a beer"?

"Grumman-581" wrote in message
...
On Wed, 9 Aug 2006 10:12:00 -0700, "Al"
wrote:
On that hot day at high altitude, over an obstacle, which takeoff
performance chart do I use?

The one that says, "stay on the ground and have a beer"?

Ding! You win. This is of course the right answer. (and I like your style)

Al G

"Al" wrote in message ...
:
:
: There is also the issue of performance. As I understand it, alcohol
: doesn't produce as much horsepower per volume as does avgas. If I use a
: mogas that has alcohol in it, I don't have the "Get up and GO" that I used
: to have. On that hot day at high altitude, over an obstacle, which takeoff
: performance chart do I use?
:
: Al G
:
:

It is a power to weight issue. If you are pulling 28" at holding 2650 RPM, alcohol or gas it is the same power. You just
need to move more alcohol through the engine to do it. This is the primary reason there are special cars that can run
the e85 stuff - they have bigger carb jets so they can maintain the correct egr.

I suppose there would be issues on low pressure altitude days where and airplane engine may be starving for fuel (to
lean) if it is fed alcohol...

".Blueskies." wrote:

"... there are special cars that can run the e85 stuff - they have
bigger carb jets so they can maintain the correct egr.

What's a carburetor? (Asks the auto owner)

".Blueskies." wrote in message
m...

"Al" wrote in message
...
:
:
: There is also the issue of performance. As I understand it, alcohol
: doesn't produce as much horsepower per volume as does avgas. If I use a
: mogas that has alcohol in it, I don't have the "Get up and GO" that I
used
: to have. On that hot day at high altitude, over an obstacle, which
takeoff
: performance chart do I use?
:
: Al G
:
:

It is a power to weight issue. If you are pulling 28" at holding 2650 RPM,
alcohol or gas it is the same power. You just
need to move more alcohol through the engine to do it. This is the primary
reason there are special cars that can run
the e85 stuff - they have bigger carb jets so they can maintain the
correct egr.

I suppose there would be issues on low pressure altitude days where and
airplane engine may be starving for fuel (to
lean) if it is fed alcohol...

So, I just run it richer? Or, in the case of a departure, where the
mixture is already full rich, you're saying there will be NO loss of
performance by using a mixture of autogas and alcohol?

Al G

Jim Macklin wrote:
ECON 101

AvGas is available at X price
MoGas is available at 3/4X price
Cost to re-refine MoGas Y (why is a good choice of letter)
Cost to repair damaged engine (each) $20,000.

Cost to repair damaged fuel tanks, plumbing, pumps and
seals, unknown.

Cost of FAA violation of regulations, certificate
suspension, a lot
Cost of uninsured aircraft when your insurance is cancelled,
priceless.


Seeing large percentage of fleet GROUNDED when avgas goes away:

????????????

Avgas is on borrowed time.

Years ago, decades even, I remember the idea that aircraft were going
to have to operate on one of two fuels, automotive gasoline or Jet A.
And someone said that aircraft fuel systems needed to be built
impervious to alcohols, anilines, aromatics, or any other Bad Thing
thet might conceivably wind up in automotive gasoline.

The Rutanoids were running fuel on primary composite structure and I
said then, "You better make sure _no_ fuel can attack it". Oh no,
nothing but avgas was ever going in there. They wish they'd listened
now.

The diesels-primarily the (autoderivative!) Thielert/Centurion-are
sawing a hole in Lycoming's future, in case you hadn't noticed. Flight
schools over here and everyone in Europe is lining up for STC
conversions. Avgas will be no longer available in Europe in a short few
years and over here in a couple after that.

The Brazilians have had some success running some aircraft on straight
ethanol, and if one could get someone to build conformal pressure
tankage LP Gas might be possible-P&W radial powered helos have flown on
it. But otherwise, it's car gas, or convert to diesel or turbine.

The way that the fuel price is going, a large percentage of U.S. GA
fleet will ground themselves in about 5 years.

It's a sad future indeed, but GA as we know it here is going away very
soon. It'll be largely replaced by ultralights/LSAs burning mogas.
The 100LL Bonanza/Mooney/Cirrus flyers will be able to hold out for a
while buying increasingly expensive 100LL, but they'll give up
eventaully, or buy a turboprop if they have the money.

The light twin fuel hogs will be the first to go.


Bret Ludwig wrote:


Seeing large percentage of fleet GROUNDED when avgas goes away:

????????????

Avgas is on borrowed time.

"M" wrote in message
oups.com...

The way that the fuel price is going, a large percentage of U.S. GA
fleet will ground themselves in about 5 years.

It's a sad future indeed, but GA as we know it here is going away very
soon. It'll be largely replaced by ultralights/LSAs burning mogas.
The 100LL Bonanza/Mooney/Cirrus flyers will be able to hold out for a
while buying increasingly expensive 100LL, but they'll give up
eventaully, or buy a turboprop if they have the money.

The light twin fuel hogs will be the first to go.

Funny, the same thing has been said since aviation began. Read some
magazine articles from the '20s, 30s, 40s, 50s, 60s, 70s, 80s and 90s and
you read the same story over and over again.

"Jay Honeck" wrote:

The adding of ethanol to gasoline has made the auto-gas STC unusable
for many aircraft owners, nationwide. So far, we're okay (in Iowa,
which is pretty funny) and are able to purchase untainted mogas -- but
the long-range situation seems untenable. We, as a nation, are
inexorably being forced toward the addition of alcohol into ALL
gasoline, so it seems...

On the Cherokee 235 user's group, there is a guy who's been
successfully using ethanol-gas in his aircraft. It's ruined his
fiberglass tip tanks, but he apparently expected this to happen.
Otherwise, the engine is running fine, or so he reports. (Personally,
I think he's crazy, ruining tip tanks that run close to $4K *apiece*,
but that's just me...)

Longer term, he is also risking corrosion damage to main tanks and pumps,
since ethanol, being hygroscopic, tends to join with any water, including
that from humidity in the air, and settle to the bottom of tanks. This
is a particular problem where humidity is high, and the fuel is left in
the tank for any period of time before being used.

The water content can also add to the risk of vapor lock or ice crystals
forming in the fuel where those things are already a problem, such as
where winter grade fuel is not used until the heat of the summer.

His experience has led to a more interesting (to me) discussion about
the possibility of REMOVING ethanol from gasoline. Several ideas have
been postulated (evaporation; heating; adding water), but none of them
sound particularly safe or easy.

Any chemists out there? Anyone know a way to remove the ethanol from
mogas, so that we may safely use it in our aircraft?

Without directly answering the question, also keep in mind that ethanol
is an octane booster. If it is removed from E10 fuel, as an example,
there is a loss of 2 or 3 points of octane. (This is also a problem
where the ethanol has combined with water and dropped out of the gasoline
mix.)

An engine like a Rotax turbo approved for use of Mogas requires a minimum
of 91 or 92 octane, and that is the rating for premium fuel. Thus, if
the ethanol is removed, even from premium fuel, the octane wouldn't be
high enough to use in the engine. The only possibility would be to start
with Sunoco Ultra, which is a 94 octane fuel, which I understand is 93
octane without the ethanol. Perhaps Sunoco will offer it as mogas
without the ethanol.

One way of removing ethanol would be to mix water with the fuel, and let
it sit for a while. The ethanol would combine with water, then you could
drain both off, (along with any other soluble compounds in the fuel).

One way of removing ethanol would be to mix water with the fuel, and let
it sit for a while. The ethanol would combine with water, then you could
drain both off, (along with any other soluble compounds in the fuel).

This is one of the options being discussed on the 235 group. It
apparently works, but it sure isn't practical, IMHO.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"