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Diesel vs Kerosene

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Diesel vs Kerosene

Old 12-15-2013, 07:58 AM
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dbsonic
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Default Diesel vs Kerosene

It looks like diesel #2 actually weighs a little more per gallon than kerosene. JetA and kero are 6.8lbs per gallon and looks like diesel is a little more weighing in at 7.0 lbs. Although some sources quote 7.2lbs. What are people noticing when they switch from kero to diesel in terms of flight characteristics?

Darren
Old 12-15-2013, 08:02 AM
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mtnflyer14
 
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I didn't notice any difference in performance, but was/am happy to buy diesel at the same service station I buy gasoline and for about $1.50 less per gallon. Availability and cost - that is the real advantage, in my mind. And, for what it's worth, Kingtech recommends 3% oil with diesel as opposed to 5% with kerosene.
Regards,
Gus
Old 12-15-2013, 08:16 AM
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afterburner
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No difference here as well in my Rabbit and Cheetah. JC recommends around 2% when using diesel as opposed to 2.5% on kero. Only noticeable difference to me was more exhaust smoke on shutdown.
Old 12-15-2013, 08:16 AM
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JackD
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Darren,

The only thing I notice is smoke on start up and shut down. Other than that, I have seen absolutely no difference.
Old 12-15-2013, 01:58 PM
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CraigG
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Originally Posted by JackD
Darren,

The only thing I notice is smoke on start up and shut down. Other than that, I have seen absolutely no difference.
+1 except that the smoke on shutdown is more than just a nuisance to me. It always looks like there's a fire and even though I know it's just the diesel, I worry it might be masking a real fire. It bothered me enough that I went back to Jet A/Kerosene.

Craig
Old 12-15-2013, 04:25 PM
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d_wheel
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Any problem starting a kero start engine with diesel?

D.W.
Old 12-15-2013, 04:47 PM
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Originally Posted by d_wheel
Any problem starting a kero start engine with diesel?

D.W.
Both my Rabbit and Cheetah are kero start but it depends on the manufacturer. I believe JetCat does not recommend diesel in any of their engines whether kero or gas start.
Old 12-15-2013, 05:35 PM
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d_wheel; not if you own a Kingtech.
Regards,
Gus
Old 12-15-2013, 05:44 PM
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Thanks guys. Flew today and just like you said, no difference except for smoke on shutdown. I could not tell any difference while flying with it being slightly heavier, and amount burned was about the same judging by level in the tanks after flight using same timer. good power.

I did not know about the reduced oil advantage(I'm running a K180). I ran it with 5% like I would with kero. would guess that doesn't hurt.

Last edited by dbsonic; 12-15-2013 at 05:50 PM.
Old 12-15-2013, 05:54 PM
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Gus, Darren, 5% in Diesel is good and is how I run now, but never had a problem with 3% KT oil in Diesel either. Glad that you are enjoying it Darren.

Regards,
Barry
Old 12-15-2013, 09:19 PM
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husafreak
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I have been running 2.5% in my diesel. Started with diesel in my Cheetah and don't know any better. I just do whatever Jack tells me to do, it's easy! I like the smoke on shutdown since I don't have a smoke system. Plus an added benefit is my bud Hans really likes the smell. I make sure to pit upwind of him. As for the weight don't forget the the weight changes with temperature, you could make a little chart so you know exactly what your rig weighs
Old 12-15-2013, 09:25 PM
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Hi Mary. I have Super Eagle and Rhino. Can I run diesel on these jet central engines? Both are propane starts.

Do we need to add anti static fluid into Diesel if I fly at very dry place? The main reason that I still jpuse Jet A is that it has anti fungi and anti static additives.

Mike
Old 12-15-2013, 09:35 PM
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Mike,

Check with Eric or Juan but I do believe that any motor before the "polished" cases CANNOT run diesel. It has to do with the internal temp and combustion area I believe. The Rabbit and all newer versions of the engines are cleared for diesel.
Old 12-15-2013, 09:41 PM
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Thank you. Yes. I heard about that. I will check with them just to make sure. Thanks. Mike
Old 12-15-2013, 09:54 PM
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According to the flow meter and various other measuring devices at the factory test bench, Chuang concluded the following when running Diesel:

1) 10 to 12% better fuel efficiency
2) 3 to 5% higher thrust

Regards,
Barry
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Old 12-15-2013, 11:51 PM
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Any proven ECU changes to setup for K140F for running on diesel? Have been running Paraffin through mine for 3 years.

Last edited by DominicM; 12-16-2013 at 12:27 AM.
Old 12-16-2013, 02:20 AM
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I have been running diesel and 2.5% oil in my Boosters since the beginning.

m
Old 12-16-2013, 03:40 AM
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Mike, please let us know if you speak to Eric or Juan because I asked and was told I could run it in my Eagle as well. I haven't done it for that engine yet as I haven't flown that plane but I wouldn't have switched to diesel if I couldn't run it in all my Jetcentral engines. I don't want to have to have two different fuelers. Thanks.
Old 12-16-2013, 05:42 AM
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I switched to diesel in the spring and right from the get go noticed that my wallet prefers diesel Diesel is 1/3 the cost of kero for me. I also felt that there was a slight increase in power over the kero, as Diesel burns hotter it makes sense. A lot of people comment on the smoke during shut down and when backing off the throttle in flight... but then they just laugh it off as being more Scale Like
Old 12-16-2013, 05:42 AM
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I've only got a few flights with diesel, and the smoke got my attention when I first ran the engine on the stand. I'm not crazy about the smoking - in fact, I don't like it very much at all - but I got used to it. On the other hand, I like the convenience of availability and lower cost of diesel more than I dislike the smoke.

Barry says the engine makes more thrust with diesel, and with better fuel burn numbers at equivalent thrust numbers, than with kero. I've got no way to measure this for sure, but Barry seems like a stright-shooter to me, so I'll take his word for it.

So, I agree with Gus...and Craig....and Barry. Heck, I'm sounding like a politician, "I feel strongly both ways!"
Old 12-16-2013, 06:50 AM
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I am using diesel in all my engines (Jetcat and Kingtech). No negative issues at all.
I use Kingtech oil (3%). It has all the necessary additives added.

The only complain comes from my club's buddies: they claim that now the field smells like a "bus stop" instead of an airport

Will see when Jetcat services my engines if there is a consequence of using diesel. I am not worried at all.
In my opinion, using less oil (3%) is convenient in order to maintain the same lubricating fuel flow to the bearings.
I always use the "Mr. Funnel" to filter the diesel and remove any water.


Jack
Old 12-16-2013, 07:35 AM
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do you guys have different settings for diesel esc for your turbines? I know kingtech has them, and I had to tweak slightly.

For my Behotec Engines, I found lowering Kerosene modulation and lowering pump ramp up voltage would reduce flames.

Diesel seems to make some more flames than kerosene on default turbine settings it seems, so have you guys had to adjust your settings on Jet Central and other tubines?

Also long term use is something in the back of my mind, I'm wondering what are the long term affects of Kero/JETA vs ULSD (ultra low sulfur diesel) are.

Also I don't belive its a sulfur issue because ULSD has 15ppm of sulfur, the same as K-1 Kerosene.
Old 12-16-2013, 08:00 AM
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Falcon 64
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Originally Posted by marquisvns


According to the flow meter and various other measuring devices at the factory test bench, Chuang concluded the following when running Diesel:

1) 10 to 12% better fuel efficiency
2) 3 to 5% higher thrust

Regards,
Barry
I read somewhere that diesel mixed whith 10% gasoline has the highest "burn value", meaning the most efficient fuel per unit among the petro-fuels we have.
It was a German article I remember..
This in itself should result in a ditto lower % consumption at the same thrust compared to all other regular fuels, meaning carrying less weight/longer flight.
Anyone tried that mix?

Last edited by Falcon 64; 12-16-2013 at 09:05 AM.
Old 12-16-2013, 06:43 PM
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Originally Posted by Falcon 64
I read somewhere that diesel mixed whith 10% gasoline has the highest "burn value", meaning the most efficient fuel per unit among the petro-fuels we have.
It was a German article I remember..
This in itself should result in a ditto lower % consumption at the same thrust compared to all other regular fuels, meaning carrying less weight/longer flight.
Anyone tried that mix?

Probably not a good idea as the gasoline will raise the combustion temp significantly and could burn through your can. Mixing gasoline in diesel was common in winter 30 years ago, In todays modern direct injection diesels the fuel pump raises the pressure enough that a gas/diesel mix can explode in the pump.
Old 12-16-2013, 07:11 PM
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Falcon 64
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.....The ECU takes care of the turbine.. This is at the core of the subject...

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