Shrike Commander in Alaska crashed because it was fueled wrong.

It happens a lot with larger piston twins (Commanders, QueenAirs, etc...). People just assume things that size are turboprops.
Since they are likely marked as to fuel type, should the fueler be criminally liable? Or the pilot, for failing to see what was happening? AvGas in a jet can be a non-event—in some cases, the pilot may never even know—but not the other way around.
 
should the fueler be criminally liable? Or the pilot, for failing to see what was happening?
FYI: Unless you want to certify refuelers/line guys and/or create a new law/rule covering same there's zero path to anything criminal. Besides there's already a person who is liable... the pilot per the FARs. Have seen a number of these types incidents work through the systems and every one ends up in the pilots lap as certain servicing like fueling and oil level checking is considered aircraft preflight tasks, i.e., pilot tasks. Add to that a pilot certificate/rules does not allow the use of others to perform those tasks like an A&P can supervise/oversee non-certified persons work. So while it's common to have a line guy fill the tanks and add a quart of oil, it falls to the pilot whether it was done properly.
 
Criminalizing stupid will have 10% of the population as prison guards, guarding the rest of the population. In this case, perhaps the pilot and the refueler would be cellmates.
 
Worth linking, very relevant with hands-on testing done for those who say it's easy to see:
https://www.pilotsofamerica.com/community/threads/avgas-and-jet-a-contamination-results.74702/

Not bad, but the "hold it up to the blue sky to see the color difference" method is, at best, pretty foolish and one of the things I strongly advise against with my students. Put the pure 100LL next to a contaminated sample against a white background and the difference is very obvious.
 
Not bad, but the "hold it up to the blue sky to see the color difference" method is, at best, pretty foolish and one of the things I strongly advise against with my students. Put the pure 100LL next to a contaminated sample against a white background and the difference is very obvious.

Only did that test because someone asked for it.

And the side by side might be true (I didn't check) but how often do you have two fuel sources when testing your fuel? Comparing two fuels samples from a misfueled plane would both look pretty blue compared to each other.

If I was still working in line service I'd test it ASAP ;)
 
Only did that test because someone asked for it.

And the side by side might be true (I didn't check) but how often do you have two fuel sources when testing your fuel? Comparing two fuels samples from a misfueled plane would both look pretty blue compared to each other.

If I was still working in line service I'd test it ASAP ;)

Yah.. I guess I was unclear for sake of brevity. I was not suggesting that one should compare samples each time. However, if you take the time to create contaminated samples as examples (I used glass jars that once held bullion cubes) and compare them side by side, you will see how "blue" it should look. Later, when you do see a Jet A contaminated 100LL sample, it will be pretty obvious so long as you are not holding it against a blue background.

For me, color is actually a secondary indication. I smell every sample I pull. Mostly because I kinda like the "worm dirt" smell of the 100LL. Even a tiny amount of Jet A will trigger flashbacks of three years on a USN oiler. :confused:
 
Yah.. I guess I was unclear for sake of brevity. I was not suggesting that one should compare samples each time. However, if you take the time to create contaminated samples as examples (I used glass jars that once held bullion cubes) and compare them side by side, you will see how "blue" it should look. Later, when you do see a Jet A contaminated 100LL sample, it will be pretty obvious so long as you are not holding it against a blue background.

For me, color is actually a secondary indication. I smell every sample I pull. Mostly because I kinda like the "worm dirt" smell of the 100LL. Even a tiny amount of Jet A will trigger flashbacks of three years on a USN oiler. :confused:

Understood! I still miss the smell of Jet-A in the morning...
 
Understood! I still miss the smell of Jet-A in the morning...

We carried 3M gallons of DFM and 2M gallons of JP5 (essentially just a cleaner grade of DFM). The smell penetrated everything. Never thought I would miss it... but here we are 30 years later and... :oops:
 
We carried 3M gallons of DFM and 2M gallons of JP5 (essentially just a cleaner grade of DFM). The smell penetrated everything. Never thought I would miss it... but here we are 30 years later and... :oops:

My wife absolutely doesn't miss it! Only 5000 gal at a time for me but I can't count how many times I filled that truck up!
 
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Unfortunately, many of the places you're likely to get misfueled have enough turbine traffic that the place reeks of JetA anyhow. The time I was really nervous was when someone had parked his turboprop Bonanza conversion next to me. It made the area reek of JetA.

It doesn't take much JetA to render the octane of AvGas unusable. I'm still not convinced that you could always detect it by smell, color, or "greasiness" in lethal amounts.
 
It doesn't take much JetA to render the octane of AvGas unusable. I'm still not convinced that you could always detect it by smell, color, or "greasiness" in lethal amounts.

Then how?
 
Unfortunately, many of the places you're likely to get misfueled have enough turbine traffic that the place reeks of JetA anyhow. The time I was really nervous was when someone had parked his turboprop Bonanza conversion next to me. It made the area reek of JetA.

It doesn't take much JetA to render the octane of AvGas unusable. I'm still not convinced that you could always detect it by smell, color, or "greasiness" in lethal amounts.

Jet A is about 50 octane, assume linear property blending.

The evaporation test is pretty good... avgas gone in seconds. Jet just hangs around...

Paul
 
Jet A is about 50 octane, assume linear property blending.
You're off by 100%. It's less than 25.

The evaporation test is pretty good... avgas gone in seconds. Jet just hangs around...
That presumes you are using pure Jet A. As I stated, I'm not confident that the evaporation test will detect a mix of Jet A and 100LL . It only took 10% to induce serious detonation. Unlike modern auto engines that would just retard themselves rather than face detonation (which would be bad enough in flight), running a JetA mix can cause serious physical damage to the engine. I got a bunch of accessories off a trashed GO that got something like a 10% Jet A mix.
 
Just to chime in here having lived in Aniak and saw multiple aircraft fueled from the truck - at least while we were there the fuel truck operators would put one of those fueling mats designed to keep the hose off from rubbing on the leading edge over. My guess is that the fueler slapped the mat over the port before climbing the ladder high enough to see any markings.
Not that this absolves anyone, only a possible link in the chain.
 
Flying/owning aircraft is all about risk management IMHO. I always supervise fueling, one less thing to worry about.
 
the California Fullerton News-Tribune, said:
“There isn’t a man alive who hasn’t made a mistake. But I’m positive you’ll never make this mistake again. That’s why I want to make sure that you’re the only one to refuel my plane tomorrow. I won’t let anyone else on the field touch it.”
When Bob told the story, he would say he was going to kill whoever fueled his plane. He stormed into the FBO asking them who did it. They wouldn't answer him and he asked multiple times. Finally, someone pointed to a kid leaning against the fence outside with his head down. He went out with the intention of ripping him a new one and as he got closer it came to him that he could destroy this kid, but maybe there was a better way.

If you're a pilot and you haven't already read Forever Flying... order a copy today. You won't regret it.
 
1) Why is Prist not a give away for the pilot?

I had an FBO ask me that once, but having no turbine experience at all, I had no idea what she was asking.
 
Since they are likely marked as to fuel type, should the fueler be criminally liable? Or the pilot, for failing to see what was happening? AvGas in a jet can be a non-event—in some cases, the pilot may never even know—but not the other way around.

No, it should not be criminal unless you have evidence of intent.
 
I had an FBO ask me that once, but having no turbine experience at all, I had no idea what she was asking.

Not all Jet A burning engines are turbines. The only reason I knew about Prist prior to this thread is because the DA-42 is a Diesel engine that normally burns Jet A (but can run automotive diesel, with restrictions, if necessary).
 
I had an FBO ask me that once, but having no turbine experience at all, I had no idea what she was asking.
Prist is a FSII or fuel system icing inhibitor. Jet fuel always has a certain % of water suspended in it naturally and is impossible to remove. As as the aircraft climbs and the jet fuel cools in the wings, water can come out of solution. Since the water is more dense than the jet fuel, it sinks to the bottom of the tank and it can freeze in the form of ice crystals, causing all kinds of issues for the fuel system and filters.

Smaller jets (like the Beechjet or smaller Citations) don't have fuel heaters/etc so they ask for "positive Prist" when the fueler is refueling their aircraft. There's a little switch on the truck that starts an injector that pulls Prist from a tiny container on the truck and adds it to the regular jet fuel as it goes through the hose to the aircraft. There's also pre-mixed jet fuel where the Prist is added before it gets to the FBO fuel tanks.

Larger jets have protection against fuel system icing built in so they don't NEED Prist although I was asked maybe 1/4 of the time to add Prist anyway to combat microbial growth in the tanks.
 
causing all kinds of issues for the fuel system and filters.
FYI: there are also several types of turbine engine fuel filter designs that allow cold weather operation without the use of anti ice fuel additives. The filter is designed to capture the ice particles.
 
FYI: there are also several types of turbine engine fuel filter designs that allow cold weather operation without the use of anti ice fuel additives. The filter is designed to capture the ice particles.

The more you know! Are they widespread? And what models tend to have these?
 
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Prist is a FSII or fuel system icing inhibitor. Jet fuel always has a certain % of water suspended in it naturally and is impossible to remove. As as the aircraft climbs and the jet fuel cools in the wings, water can come out of solution. Since the water is more dense than the jet fuel, it sinks to the bottom of the tank and it can freeze in the form of ice crystals, causing all kinds of issues for the fuel system and filters.

Smaller jets (like the Beechjet or smaller Citations) don't have fuel heaters/etc so they ask for "positive Prist" when the fueler is refueling their aircraft. There's a little switch on the truck that starts an injector that pulls Prist from a tiny container on the truck and adds it to the regular jet fuel as it goes through the hose to the aircraft. There's also pre-mixed jet fuel where the Prist is added before it gets to the FBO fuel tanks.

Larger jets have protection against fuel system icing built in so they don't NEED Prist although I was asked maybe 1/4 of the time to add Prist anyway to combat microbial growth in the tanks.

I was flying my Cardinal when they asked if I wanted Prist.
 
I was flying my Cardinal when they asked if I wanted Prist.

Eesh. Yeah, I've heard it asked by one of our customer service reps while I was helping a 172 unload pax and bags. They know not what they say :(

I've also had to deal with the same customer service reps badgering single piston pilots to top their tanks off so we get paid as much money as possible. They didn't understand the issues with weight and balance and that you can't just fill up the tanks in a plane like you fill up a car. The same people vocally detested serving small plane pilots. Absolute stupidity there.
 
Today was the day our 3-month long annual and panel upgrade was finally done. As they were fixing a little issue with the airplane I asked their desk to have the tanks topped. Imagine my surprise when I pulled a sample from the tank and it did not look "Blue" enough... Told the guy, "This is contaminated." Then I smelled it... It smelled vaguely like a truckstop. Then I felt it... It was greasy.

Yah... This stuff happens.

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Today was the day our 3-month long annual and panel upgrade was finally done. As they were fixing a little issue with the airplane I asked their desk to have the tanks topped. Imagine my surprise when I pulled a sample from the tank and it did not look "Blue" enough... Told the guy, "This is contaminated." Then I smelled it... It smelled vaguely like a truckstop. Then I felt it... It was greasy.

Yah... This stuff happens.
In my experience, the amount of dye in the fuel can change significantly between different fuel suppliers - kind of how jet-A can be clear to straw. Did you do the paper test to check for the halo/oil left behind? And if that's the case they need to know to remove that truck or tank from service ASAP.
 
In my experience, the amount of dye in the fuel can change significantly between different fuel suppliers - kind of how jet-A can be clear to straw. Did you do the paper test to check for the halo/oil left behind? And if that's the case they need to know to remove that truck or tank from service ASAP.
What is the paper test?
 
That’s very, very rare. I can’t even think of an example. Maybe some national security issue type stuff.
It's even on the books in most states as "criminal negligence", meaning that the act that you are doing has great potential for harm if mishandled (anything from leaving the toddlers alone in the pool, shooting your gun into the air at the New Year, backing up a big truck in a school yard without a spotter, or refueling an airplane. Sort of an endless list; it's a "catch-all" law.)
 
Are they widespread? And what models tend to have these?
The filters are mainly found with small turboshaft engine installs. For example, most turbine helicopters have an "ice-compatible" external fuel filter, either as an option or standard, and are exempt from FSII use depending on the grade fuel used. Given how toxic Prist can be, it made mx work on the fuel systems more "enjoyable" once the fleet aircraft were retro'd/delivered with external fuel filters. Here's one example:
https://www.airbushelicopters.ca/optional-equipment/airframe-fuel-filter-3/
 
or refueling an airplane.
While it maybe on the books, criminal negligence is a very high bar to reach. Have seen it's use attempted at the mechanic level, but never seen or heard it making it through court where it stuck. Even when a mechanic knowingly performed something that resulted in a fatality the use of criminal neg is usually a dead end. So, in my experience, trying to apply that to a refueler would not be an available path given a pilot is legally responsible for the pre-flight requirements of his aircraft with no relief to delegate or even supervise the refueling. However, on the civil tort side, anything is possible and "fair" game.
 
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I may have to pop over to the next airport and buy a pint of JETA to test at various mixtures. I wish I had thought of this when the MU-2 was parked in my front yard, I probably could have tapped that for a few ounces.
 
In my experience, the amount of dye in the fuel can change significantly between different fuel suppliers - kind of how jet-A can be clear to straw. Did you do the paper test to check for the halo/oil left behind? And if that's the case they need to know to remove that truck or tank from service ASAP.

I did the paper test as a backup to my already proven smell and greasy finger test. Only because they said the same thing. Color varies. Apparently they could not smell the Jet. I could. Once they cleaned and refilled with fresh, there was a significant difference. No more kerosene smell, no more greasy fingers. Just a fresh "worm dirt" smell and rapidly drying fingers.

I kept the paper. It still smells like a truckstop.
 
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