Mixing 100 & 100LL - What Color is It?

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KennyFlys

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This came up during a ground session today. I've heard the answer but a lot of fuel has been burned since that time umpteen years ago. I've never even seen the red 80 in use... ever! That's going back to at least 1981. Is it around at all these days?

But, the point of the post...

What color results when mixing Red 80 and Blue 100LL?

Edit: Red type is correction my error.
 
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KennyFlys said:
This came up during a ground session today. I've heard the answer but a lot of fuel has been burned since that time umpteen years ago. I've never even seen the red 100 in use... ever! That's going back to at least 1981. Is it around at all these days?

But, the point of the post...

What color results when mixing Red 100 and Blue 100LL?
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I remember red being 80 octane and green being 100, but I haven't seen either in probably 15 or more years.
 
KennyFlys said:
This came up during a ground session today. I've heard the answer but a lot of fuel has been burned since that time umpteen years ago. I've never even seen the red 100 in use... ever! That's going back to at least 1981. Is it around at all these days?

But, the point of the post...

What color results when mixing Red 100 and Blue 100LL?
Click to expand...

These are the fuel colors:

- Avgas 80 octane color = Red
- Avgas 100 octane color = Green
- Avgas 100LL octane color = Blue
- Jet Fuel color = clear or straw color

If you mix them, theoretically it would turn clear.
I can't say I have ever seen straight 100 Octane. In fact, I think it was classified 100/130 octane.
 
Everskyward said:
I remember red being 80 octane and green being 100, but I haven't seen either in probably 15 or more years.
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Oops! Sorry, I was in such a rush I typed 100 for the red. I meant 80. I've never seen it so the question might still hang out there. I vaguely recall eons ago the 100/130. I've never seen that or the Green 100.

Another pilot just mentioned 80 and 100LL mixed will turn clear but he wasn't sure.

I responded.... "So, it turns into jet fuel?" :)
 
It you mix Red 80 and Blue 100LL you get clear.

Done that.

Wish I could still find 80.
 
Aviation fuel dyes are designed to cancel their colors when mixed, so if mixed in equal parts, the mixture should be clear (not straw colored, so don't put it in your jet :)

Not that I'm old or anything, but I've used 80. 100 and 100LL, and demonstrated the color cancellation to students numerous times.
 
DGlaeser said:
Aviation fuel dyes are designed to cancel their colors when mixed, so if mixed in equal parts, the mixture should be clear (not straw colored, so don't put it in your jet :)

Not that I'm old or anything, but I've used 80. 100 and 100LL, and demonstrated the color cancellation to students numerous times.
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What's that river in Egypt called again? Da Nile? :)

I don't think I've noticed ya on the board, before. Thanks for the help and welcome!
 
DGlaeser said:
Aviation fuel dyes are designed to cancel their colors when mixed, so if mixed in equal parts, the mixture should be clear (not straw colored, so don't put it in your jet :)
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Of course, in small doses, it doesn't make that much difference in a jet. You don't want to make a habit of it, but a jet WILL run on avgas. The more diluted the better.
 
If you mix 100/130 and 100LL you get greenish-blue. I guess they didn't find it necessary to make the dyes cancel each other out since airplanes originally designed for 100/130 would also run on 100LL.
 
Everskyward said:
If you mix 100/130 and 100LL you get greenish-blue. I guess they didn't find it necessary to make the dyes cancel each other out since airplanes originally designed for 100/130 would also run on 100LL.
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LOL. Where did you come across that knowledge? I have never seen 100/130 in 31 years of doing this.
 
Greg Bockelman said:
LOL. Where did you come across that knowledge? I have never seen 100/130 in 31 years of doing this.
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Back when I worked in Boise (1985-6) flying an old C206 I can remember the mechanic or someone telling me to fill it with 100/130 if it was available as a choice. It wasn't available in very many places but I was able to find it on occasion. It was usually at some obscure airport and had probably been in the tanks for 10 years...
 
Did 100 have less lead than 100LL, but 80 has more lead than 100LL or do I have that reversed?
 
Anthony said:
Did 100 have less lead than 100LL, but 80 has more lead than 100LL or do I have that reversed?
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Since you asked:

80 octane has the least lead of the bunch.
100LL has about 4 times as much lead as 80 octane.
I have to believe 100/130 has even more lead than 100LL but I don't know. That is the question I would like someone in the know to answer. :yes:
 
Greg Bockelman said:
80 octane has the least lead of the bunch.
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Ahh, yes, thanks Greg. That's why the low compression O-320 in my old Cherokee liked the 80 octane better than 100LL. My Tiger can only run on 100 or 100LL due to the higher compression O-360.
 
Greg Bockelman said:
I have to believe 100/130 has even more lead than 100LL but I don't know. That is the question I would like someone in the know to answer. :yes:
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Yup...that's why they call it 100LowLead.

I just wish mixing red 80 with blue 100LL resulted in 145 octane purple...and I know a guy who claims he burned the last batch of that stuff in a firebomber. ;)

Fly safe!

David
 
Greg Bockelman said:
You don't want to make a habit of it, but a jet WILL run on avgas. The more diluted the better.
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A jet will run on virtually flammable liquid including tequlia.

Wiki said:
http://en.wikipedia.org/wiki/Chrysler_Turbine_Car
The fourth-generation Chrysler turbine engine ran at up to 60,000 rpm could use diesel fuel, unleaded gasoline, kerosene, JP-4 jet fuel, and even vegetable oil. The engine would run on virtually anything and the president of Mexico tested this theory by running one of the first cars--successfully--on tequila.
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.
 
This has to be a trick question and the answer is blue. Your mixture ratio would be 0% 80 octane and 100% 100LL as the 80 doesn't exist anymore.
 
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