Contrails from 100LL?

455 Bravo Uniform

455 Bravo Uniform

Final Approach
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455 Bravo Uniform
My son had an interesting question when we were talking about contrails and tin-foil hats.

Do non-turbine engines or engines burning other than Jet A create contrails?

I have not a clue. It would seem plausible, since we're still turning fuel into CO2 and H2O in piston engines.
 
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Gasoline-powered engines can make contrails. Generally, gas-powered planes mostly no longer fly where they can make contrails (I'm thinking high levels where jets fly, not conditions conducive to contrails lower down)
 
Yes, water vapour is a byproduct of oxidizing 100LL. But the creation of a contrail means that water vapour is condensing in clear air, and I don't believe aircraft that burn 100LL fly at those altitudes habitually.
 
455 Bravo Uniform said:
My son had an interesting question when we were talking about contrails and tin-foil hats.

Do non-turbine engines or engines burning other than Jet A create contrails?

I have not a clue. It would seem plausible, since we're still turning fuel into CO2 and H2O in piston engines.
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B-17s were making contrails back in WWII.
 
GRG55 said:
Yes, water vapour is a byproduct of oxidizing 100LL. But the creation of a contrail means that water vapour is condensing in clear air, and I don't believe aircraft that burn 100LL fly at those altitudes habitually.
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It's not necessarily the altitude. It's the temperature. I've had contrails taking off in a C-207 up in Alaska.
 
I recall as a little kid seeing B-36's flying high and leaving contrails.
 
Anymouse said:
We stopped flying at -30F in the piston birds, but yep!!
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Lucky you. When I worked winters in Ak we stopped at anything lower than -40. Lower than -25 we used the herman nelson to warm up the engine before starting, even though we had engine blankets and electric heaters on the engine(s).

-48 was the limit for the turbines.

Nothing like starting the engine and waiting 5 minutes for the oil pressure gauge to start working.
 
Norman said:
I recall as a little kid seeing B-36's flying high and leaving contrails.
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Jet watched Strategic Air Command recently on Bluray. Lots of contrails.:)
 
Zeldman said:
Lucky you. When I worked winters in Ak we stopped at anything lower than -40. Lower than -25 we used the herman nelson to warm up the engine before starting, even though we had engine blankets and electric heaters on the engine(s).

-48 was the limit for the turbines.

Nothing like starting the engine and waiting 5 minutes for the oil pressure gauge to start working.
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When you get that cold, things are just too brittle and break way too easily. (I know you know, but I put it out there for the folks that don't.) Fortunately, the worst I ever had flying at those temps was rolling a tire as I was taxiing in up in Kotzebue. The day was just about done anyway fortunately.
 
I have seen vapor trails come off my 182 propeller when it was cool and humid. That was cool.
 
Those vapor trails once provided me a good visual aerodynamics lesson. I was at the approach end of rwy 3L at DTW , and it was a very humid day. The vapors provided a good look at airflow over the wings.
 
Car exhaust will be visible on cold humid days, same chemtrail idea. It just disapates much quicker.
 
Contrails aren't just from engines; any pressure drop sufficient to cause moisture to condense will do it. I once saw a Cherokee at about 2000' on a humid day pulling contrails from its wingtips.
 
From the thread title, "Contrails from 100LL?", I thought this was going to be about what happens when someone forgets to put a fuel cap back on.
 
Clark1961 said:
Well, there was that little incident with them bombing Pearl Harbor...
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I use that when teaching my students about history.

"On December 7, 1941. The Germans bombed Pearl Harbor." This year I had two students actually catch the snafu.

On another note, my wife was up at the college last week, we had the doors open and she said " get the vinegar, lots of chemtrails today!" One of my students gave us the puzzled look, so I explained chemtrails to him. He then went and looked them up and the next day we had a real nice laugh over some of the whackos out there. M
 
dell30rb said:
Maybe I am missing a joke, but that was the Japanese.
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I know it's Monday morning and we just reset the clocks and all but you just swallowed it hook line and sinker...
 
Acrodustertoo said:
I use that when teaching my students about history.

"On December 7, 1941. The Germans bombed Pearl Harbor." This year I had two students actually catch the snafu.

M
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My 6th grade world history book did not have the end of WW II in it. This was way back in 1970.
 
There's a classic quote by the late Jerome Brown, defensive tackle at University of Miami and a five-year pro career with the Philadelphia Eagles before he was killed in a car crash. Days before the 1987 Fiesta Bowl, at a promotional dinner bringing together Brown's Hurricanes and the opposing Penn State team, Brown got up and led his team in a walkout from the event, saying, "Did the Japanese go and sit down with Pearl Harbor before they bombed 'em?"

Miami lost, 14-10.
 
GRG55 said:
Yes, water vapour is a byproduct of oxidizing 100LL. But the creation of a contrail means that water vapour is condensing in clear air, and I don't believe aircraft that burn 100LL fly at those altitudes habitually.
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Not today they typically dont, but before the jet age, turbocharged and supercharged aircraft did indeed routinely fly up there...
 
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