How blue is 100LL?

Throw some of the fuel on the pavement. If it evaporates quickly, it is
avgas. If it just sits there, it is jet fuel. Avgas also acts differently if
you throw it onto a puddle of water than jet fuel does.

Anything that is put into a fuel tank is going to come out dyed blue and
smelling like gas.

I don't know. My point is that on most med to small airports, if it smells
like gas, it's going to be 100LL.

And not mogas, which has a very distinctive and unpleasant smell. The
Cubs on my airfield were STC'ed for mogas, but the instructors
complained so much that the STCs were yanked, and the planes are now
placard for 100LL.

all the best -- Dan Ford
email: (put Cubdriver in subject line)

The Warbird's Forum www.warbirdforum.com
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Viva Bush! blog www.vivabush.org

Cub Driver wrote:

And not mogas, which has a very distinctive and unpleasant smell. The
Cubs on my airfield were STC'ed for mogas, but the instructors
complained so much that the STCs were yanked, and the planes are now
placard for 100LL.

If I can smell gas of either sort during normal operations, I won't be flying that
aircraft.

George Patterson
If you don't tell lies, you never have to remember what you said.

"James M. Knox" wrote in message

So how blue is it supposed to be? Is there another simple test I could
have done to reassure myself (besides burning 30gal of it and having it
work fine)?

I've seen it all over the place. From almost navy blue (at an airport
that
doesn't get much traffic, to no discernable color at all).

Ran into this at the FBO that I fly out of at PDX-TTD. Sometimes the dye is
so pale that you have to hold it right up against a white surface such as
the vertical stabilizer to confirm the blue dye.

-c

Dribble a little fuel onto a piece of white paper...if it evaporates and
leaves behind a tint, it is avgas; if it spreads out, soaking into the
paper, it is jet fuel.


If it leaves a ring, it's jet fuel. I've been told even a little (like 5%) is
sufficient to leave a visible ring.

But yes, I've seen very pale 100LL. In fact, I've rarely seen really blue
stuff. When I got my license (1980) it was supposed to be as blue as Windex.
(in fact, that's what was used in a slide my ground instructor had to show the
fuel colors - El Monte didn't have 100LL at the time)

To top it off, my fuel tester has little plastic inserts - they are blue. I
wish they'd get smart and make them white or clear.

Jose

--
(for Email, make the obvious changes in my address)

(Ben Jackson) wrote in message news:%91jc.37417$_L6.2182786@attbi_s53...
I usually pump my own, but today I called ahead and had the FBO fill it
for me (only 53 cents more/gal!). I wasn't even present for the fueling
so I was extra paranoid during preflight, and I swear the 100LL was not
as "blue" as it usually is. It smelled like gas, and when I finally got
a big enough sample you could see a slight blue tint, but on a dip tube
I would have sworn it was clear.

So how blue is it supposed to be? Is there another simple test I could
have done to reassure myself (besides burning 30gal of it and having it
work fine)?

In certain levels of light our blue 100LL can look very clear. I'll
usually hold the sample up to the light behind a white part of the
plane. After contrasting with the white paint of the plane, the fuel
tends to look much more blue. Years ago, I almost made myself pass out
smelling the fuel from the Aeronca. I couldn't convince myself whether
or not I saw blue (I wasn't worried about mogas, I was concerned about
water since it has just rained). I got so light headed I had to
terminate the flight early. I now try to only take a quick sniff.

-Robert

"Robert M. Gary" wrote in message
om...
(Ben Jackson) wrote in message
news:%91jc.37417$_L6.2182786@attbi_s53...
I usually pump my own, but today I called ahead and had the FBO fill it
for me (only 53 cents more/gal!). I wasn't even present for the fueling
so I was extra paranoid during preflight, and I swear the 100LL was not
as "blue" as it usually is. It smelled like gas, and when I finally got
a big enough sample you could see a slight blue tint, but on a dip tube
I would have sworn it was clear.

So how blue is it supposed to be? Is there another simple test I could
have done to reassure myself (besides burning 30gal of it and having it
work fine)?

In certain levels of light our blue 100LL can look very clear. I'll
usually hold the sample up to the light behind a white part of the
plane. After contrasting with the white paint of the plane, the fuel
tends to look much more blue. Years ago, I almost made myself pass out
smelling the fuel from the Aeronca. I couldn't convince myself whether
or not I saw blue (I wasn't worried about mogas, I was concerned about
water since it has just rained). I got so light headed I had to
terminate the flight early. I now try to only take a quick sniff.

-Robert

Robert,

Next time try pouring a few ounces of the fuel onto the ramp. Fuel will soak
in, but water will bead up.

Harvey

"Eclipsme" wrote

Next time try pouring a few ounces of the fuel onto the ramp. Fuel
will soak in, but water will bead up.

And in Florida, gets you a $50,000 fine.

Bob Moore

(Robert M. Gary) wrote in
om:

Years ago, I almost made myself pass out
smelling the fuel from the Aeronca. I couldn't convince myself whether
or not I saw blue (I wasn't worried about mogas, I was concerned about
water since it has just rained).

Yeah, sure... that's your story, and you are sticking to it. G

You're right, it can be almost impossible to tell if it is really
slightly blue. And at night, where there isn't any good non-biased
light source to use, it can be impossible.

One option is, of course, to ADD water to the sample. No "bubble" and
it's *all* water.

What I usually do is first drain from the engine fuel filter, under the
theory that since the engine was running at shutdown there must be at
least a LITTLE gas in there. If it looks good, then don't pour all of
it out, and now add from the left main. If it looks good, then don't
pour all of it out and now add from the right main.

The idea is that there should always be some known fuel in the tube, so
you don't have the risk of thinking an all-tube WATER sample is fuel.

-----------------------------------------------
James M. Knox
TriSoft ph 512-385-0316
1109-A Shady Lane fax 512-366-4331
Austin, Tx 78721
-----------------------------------------------

Eclipsme wrote:

Next time try pouring a few ounces of the fuel onto the ramp.

Don't get caught. That'll get you kicked off many airports and get you fines in some
places. Gas damages asphalt.

George Patterson
If you don't tell lies, you never have to remember what you said.