Fuel

BravoHotel

BravoHotel

Well-Known Member
Is there a fuel expert here on JC? I have tried to engage several pilots about technical specifications of fuel and I have really haven't found the answer I am looking for. Here at Wake we have JP-5. What is the civilian equivalent, Jet-A? I know most of the military uses JP-8. Is the civilian equivalent Jet-A1? I heard in a conversation tonight about Jet-A1+.?

Anti icing additives: Do either JP5 or JP8 have anti icing additives? (Such as prist? ) I know Jet-A does not come with Prist. It has to be pre-mixed in the fuel, or added during pumping process. Does Jet-A1 have anti icing additives in it?

Does anyone know a good resource about bio-jet fuel? I know the Air Force has experimented with it but I can't seem to find much data.

100LL, I have read in various flying publications there is replacement trying to be developed, Any one know of any sources of open information?
 
It looks like JP-5 is just JetA. JetA is in the US, JetA1 is overseas. JetA1+ might be JetA1 with prist.

Anti-icing additives can be done in different ways. It can come mixed in with the fuel at the tank farm, so all planes get it. When I worked the line we had buckets of prist on the truck. We could flip a lever and the truck mixed it in to the lines. When we turned it off, it just pumped JetA. Or you can spray it in as you fuel the plane.
 
JP5 and JP8 are very similar, mostly a slightly different flash point. You'll find that the Air Force primarily uses JP8 and the Navy utilizes JP5. I can't speak to the Army's uses.

Either fuel will give the same performance. In the E-6 we use both, as we stand alert primarily at Air Force bases but also at Pax River, MD. The only restriction that I am aware of in our community is the requirement to use only JP5 for a month or so prior to going into a phase inspection or any maintenance requiring open fuel cells. Believe this stems from nothing more than our AvGas Free technicians only being able to certify with JP5. As such, Tinker AFB does keep a supply of JP5 as well, so we can special order it during these times.

The Anti-Icing is a separate additive, normally identified by the "+" is premixed in the truck. We are not authorized to use it. If it is "accidentally" put into the plane, there is a long procedure of fuel sampling and monitoring that must be performed. Overall, a pain in the ass. I do know that if I ever fueled my aircraft with it while deployed, my maintenance master chief would definitely be wanting to "discuss" it with me in length.

Not completely related... However, I did have an experience a few years back with an aircraft that was forming "apple jelly" in the tanks. From all the info that we had, it is caused by foreign contaminants reacting with the anti-ice properties of the fuel and turning into a nice reddish-orange sludge. Had three flame-outs on the same motor of the plane within a week, all during a time we were getting the jelly.

During a fourth, near flame-out, I was able to catch the low pressure lights illuminated on that tank and cross feed fuel. This is what FINALLY convinced them that there was a fuel tank problem, and not an engine problem. When the pulled the tank apart, they found a "diaper" in the tank that had started to disintegrate from being in there so long.
 
MercFE said:
When the pulled the tank apart, they found a "diaper" in the tank that had started to disintegrate from being in there so long.
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A diaper? As in baby evacuation containment device? Or BECD :) No I am guessing those fuel absorbent pads did someone leave it during fuel cell MX?
 
Hawks said:
A diaper? As in baby evacuation containment device? Or BECD :) No I am guessing those fuel absorbent pads did someone leave it during fuel cell MX?
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Yeah, I never heard if they were able to track it back to who did the FOD free checks on the tank. I'm sure it was probably someone that had transferred from our reach though.
 
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@MercFE , I've been puzzling over some US Patent Office patents and applications that I've been seeing pop up regarding jet fuel. Like @Hawks , I've been wondering if JC had any fuel experts. If Hawks doesn't mind, I'd like to sneak a question in here.

Excerpt from US Patent Office -

"One proposed solution to the problem of global warming involves the seeding of the atmosphere with metallic particles. One technique proposed to seed the metallic particles was to add the tiny particles to the fuel of jet airliners, so that the particles would be emitted from the jet engine exhaust while the airliner was at its cruising altitude. While this method would increase the reflection of visible light incident from space, the metallic particles would trap the long wavelength blackbody radiation released from the earth. This could result in net increase in global warming." . http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/PTO/srchnum.htm&r=1&f=G&l=50&s1=5003186.PN.&OS=PN/5003186&RS=PN/5003186

The above proposal may employ metallic nano-particles. In other patents docs, applicants want to add sulphur to the fuel, which I believe would shorten engine life. But the idea in all cases is similar to adding ethanol additives to auto fuel. In theory, airline pilots would be flying aircraft, perhaps without knowing it, that had federally mandated fuel additives designed to help the environment. Any thoughts on adding metallic nanoparticles or sulphur without adversely affecting engine life or performance?
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illuminati_chemtrail.jpg
 
Hawks said:
Is that specifically aviation fuel? Is performance similar to AVGAS 100LL? How much are you paying for a gallon?
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Not in use yet, but looks like that will be the replacement. AVGAS is about 2 $ for a lt in Vanuatu, closer to you in Kiribati it`s already 8 $ for a lt.....that`s 1600 $ a barrel/drum!
 
When I worked at FHB, we have Jet A w/ Additive already pre-mixed in our trucks. Also that is what is said on the sticker. But most places uses Jet A, and I have fueled aircrafts that has taken both JP5 and JP8 with Jet A. I have not messed with any other fuels other than AvGas 100LL.
 
MercFE said:
During a fourth, near flame-out, I was able to catch the low pressure lights illuminated on that tank and cross feed fuel. This is what FINALLY convinced them that there was a fuel tank problem, and not an engine problem. When the pulled the tank apart, they found a "diaper" in the tank that had started to disintegrate from being in there so long.
Click to expand...
Was the diaper, unleaded? :D
 
Hawks said:
Is there a fuel expert here on JC? I have tried to engage several pilots about technical specifications of fuel and I have really haven't found the answer I am looking for. Here at Wake we have JP-5. What is the civilian equivalent, Jet-A? I know most of the military uses JP-8. Is the civilian equivalent Jet-A1? I heard in a conversation tonight about Jet-A1+.?

Anti icing additives: Do either JP5 or JP8 have anti icing additives? (Such as prist? ) I know Jet-A does not come with Prist. It has to be pre-mixed in the fuel, or added during pumping process. Does Jet-A1 have anti icing additives in it?

Does anyone know a good resource about bio-jet fuel? I know the Air Force has experimented with it but I can't seem to find much data.

100LL, I have read in various flying publications there is replacement trying to be developed, Any one know of any sources of open information?
Click to expand...

To answer your questions:

JP-5 is the naval version of USAF JP-4, but with a higher flashpoint designed as a safety measure for shipboard operations. JP-5 is mostly kerosene, and is similar to Jet A.

JP-4 and Jet B are the same thing. Known as "wide cut" fuels, they are called such because they are a "cut" mixture of nearly 50/50 gasoline and kerosene. As such, they have a very low flashpoint and are very volatile fuels, but burn efficiently. JP-4 contains detergent additives, while Jet B does not. Jet B is still found in very cold climate areas.

JP-8 and Jet A are nearly identical, both being nearly completely kerosene blends. In fact, JP-8 is considered an alternative to Diesel fuel for military tactical vehicles (whereas JP-4 is not). JP-8+100 is a version of JP-8 with added thermal stabilizers as well as fuel injector detergents to combat coking and clogging by sediment/dirt of jet engines. Jet A-1 has a lower freeze point than Jet A. None of these come pre-mixed with icing inhibitors; that usually being added on-request from aircrew ordering up the fuel.

JP-7 was a special jet fuel used in the SR-71, and JP-9 is a special fuel used in Air Launched Cruise missiles for their motors.

AVGAS-wise, there used to be multiple grades with a colored dye added, and they were denoted by lean/rich rating:

80/87 Octane (Red)
91/98 Octane (Blue)
100/130 Octane (Green)
108/135 Octane (Brown)
115/145 Octane (Purple)

Now, these have been whittled down to just a few grades, and are referred to by their lean performance rating only. These are:

82UL Avgas (Purple)
100LL Avgas (Blue)
100 Avgas (Green)

NATO has it's own coding system for fuels. They are as follows:

80/87 (Red): NATO code F-12
100/130 (green), now 100LL (blue): NATO code F-18
115/145 (purple): NATO code F-22
JP 4/Jet B: NATO code F-40
JP-5: NATO code: F-44
JP-8/Jet A: NATO code: F-34
Jet A1: NATO code F-35
 
Qutch said:
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@MercFE , I've been puzzling over some US Patent Office patents and applications that I've been seeing pop up regarding jet fuel. Like @Hawks , I've been wondering if JC had any fuel experts. If Hawks doesn't mind, I'd like to sneak a question in here.

Excerpt from US Patent Office -

"One proposed solution to the problem of global warming involves the seeding of the atmosphere with metallic particles. One technique proposed to seed the metallic particles was to add the tiny particles to the fuel of jet airliners, so that the particles would be emitted from the jet engine exhaust while the airliner was at its cruising altitude. While this method would increase the reflection of visible light incident from space, the metallic particles would trap the long wavelength blackbody radiation released from the earth. This could result in net increase in global warming." . http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/PTO/srchnum.htm&r=1&f=G&l=50&s1=5003186.PN.&OS=PN/5003186&RS=PN/5003186

The above proposal may employ metallic nano-particles. In other patents docs, applicants want to add sulphur to the fuel, which I believe would shorten engine life. But the idea in all cases is similar to adding ethanol additives to auto fuel. In theory, airline pilots would be flying aircraft, perhaps without knowing it, that had federally mandated fuel additives designed to help the environment. Any thoughts on adding metallic nanoparticles or sulphur without adversely affecting engine life or performance?
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I find it interesting that they are suggesting adding sulfur to fuel to help the environment. The sulfur content of diesel fuel has been regulated down to 15ppm (historically the sulfur content has been in the 3000-5000ppm range) in an effort to reduce emissions. I am also fairly confident that metallic particles will not be added any time soon. I do engineering work on fuel systems for a major diesel engine manufacturer, and metallic debris is something that would cause serious issues. I have been working with some of our engines that are used by the military and they are tested with both Jet A and JP-8. Adding metallic particles to these fuels would wreak havoc on the fuel systems I work on, and the higher tech common rail systems only get more sensitive to debris.
 
MikeD said:
JP-8/Jet A: NATO code: F-34
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What's strange is the the CRJ manual (for our models at least) specifically allows either JetA or JP-8 but lists F-34 as a prohibited fuel. I could never figure that out as they are the same thing.
 
BobDDuck said:
What's strange is the the CRJ manual (for our models at least) specifically allows either JetA or JP-8 but lists F-34 as a prohibited fuel. I could never figure that out as they are the same thing.
Click to expand...

That's completely weird, unless in Europe they add something to the JP-8/F-34 that's not added to the standard JP-8 here. But if that was the case, there'd be some nomenclature designating that. (ie- JP-8+100)
 
BobDDuck said:
What's strange is the the CRJ manual (for our models at least) specifically allows either JetA or JP-8 but lists F-34 as a prohibited fuel. I could never figure that out as they are the same thing.
Click to expand...

In the A-10 (same general engine as your CRJ), we could only fly 3 sorties on an alternate fuel such as JP-5, before we had to make an adjustment to the fuel control unit in the engines if we were going to fly more with it. Does the CRJ manual say the same thing?
 
You know what... I just checked again and it's F40/JP4/JetB we can't use.

We are good for JetA, JetA1, JP5 and JP8. I actually was asked a few years ago at Eglin if we could take JP8 because the civilian fuel farm truck was broken and they were buying it from the Air Force instead.
 
MikeD said:
In the A-10 (same general engine as your CRJ), we could only fly 3 sorties on an alternate fuel such as JP-5, before we had to make an adjustment to the fuel control unit in the engines if we were going to fly more with it. Does the CRJ manual say the same thing?
Click to expand...

There doesn't seem to be a limit on that. It also specifically says that mixing fuels is ok. There is a temperature limitation on JetA (less than OAT of less -30C and the bulk fuel has to be verified above -29C) but otherwise, as for as the POH and FCOM go there aren't any restrictions.
 
BobDDuck said:
You know what... I just checked again and it's F40/JP4/JetB we can't use.

We are good for JetA, JetA1, JP5 and JP8. I actually was asked a few years ago at Eglin if we could take JP8 because the civilian fuel farm truck was broken and they were buying it from the Air Force instead.
Click to expand...

That makes sense now. For the A-10, JP-8 and JP-4 and NATO equivilents are primary fuels, as is Jet A and Jet B. JP-5 is an alternate fuel, as is JP-8+100; IIRC.

Funny you mention the latter. At CBP, we refuel the Citation 550s and UH-60s with JP-8 purchased from the USAF. However, for the turbine AS350 Astar helos, the JP-8 was causing coking issues in those engines (not +100), so we have our own JetA trucks we use with those birds......don't use JP-8 in them anymore.
 
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