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Ok... I have read almost the entire CARS and can't find anything that I'm looking for on this subject... although strangely enough I found stuff that I couldn't find before and no longer care about...hmmmm...


I was asked by a client if we could use diesel fuel in an emergency evacuation (in case we were attacked and had to move 50 guys out of harm's way). I know that we can in a 212 because I've done it before and seen it done many times. What I want to know is if it's legal.


According to the FM I can. According to the MM I can. What does the law say? And if we can use diesel fuel why do we use Jet Fuel?


Generally in bulk jet fuel is cheaper because of lesser taxes, but when we are buying fuel at an airport and paying $1.00 per litre for them to fill our slip tanks or drums, why don't we go to the local gas station?


And before anyone gets upset thinking that I'm advocating using truck fuel instead of something manufactured for the express purpose to which we're putting it, I'm definitely not. I would just like to see in black and white whether we can or cannot use a "non-aviation" fuel legally.


I typed so many key words into google on this my eyes were going bleary... I had to take some medicinal rum in order to lessen the pain... the pain didn't lessen but the "care factor" vanished.


Thanks guys,



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HV ------ been down this road before. The M & O Manuals will give you the number of hours between O/H's that diesel fuel can be burned. On some engines they also list other fuels and the hours that they can be burned or forbidden altogether. I've did the looking into the legalities also and also found nothing. The way it stood the last time I did it and wanted advice, was that as long as I stayed within the hours stated in the M & O Manual I was okay because that Manual backed me up. Over and above that time, then one doesn't want to have an engine problem where you go "bang" on the ground or else the fact that you went over that approved time might "get you". I've burned lots of Arctic Diesel over the years and many of the engines' M & O Manuals for the a/c I was flying allowed up to 25hrs between O/H's for that fuel. There was also a tolerance for other fuels, but the tolerance for the hours burned varied. In short, I believe that you will find that the M & O Manual will be "calling the shots" on this one and I'd go with what the engineer tells me. Most Ops Manuals don't address this situation and it's my personal belief that they should.

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Guest Bullet Remington



Basically, diesel fuel would be about JP-8. while jet a or jet b would be around JP 4 and jp 5.


We did a project while I was stationed at AETE on the CF5s. Did a project where we burned diesel fuel (JP-8) rather than JP-4 or 5 (Jet a or B) The diesel fuel burned, but not very well. Oh, no doubt it will burn but the calorific value of diesel is way below that of jet fuel.


We ended up changing the ignitors and we had to adjust the T5B. Plus the exciter boxs for some reason were being changed out alot. Probably because the ignition point was lower with the diesel fuel than with the Jet fuel.


As for the reference, I know I've seen and read a couple of Transport lettere/Policy memos on the use of diesel somewhere on the TC site.


As soon as I get done writting the latest manual, I go have a search and see if i can find it.


So, basically but, you will need more diesel to obtain the same power. That is to say, one will get more calorific value from one ounce of Jet Fuel than they would get from say 4 ounces of diesel.


Those old engines will burn 100ll too. But I'm not sure just how long you'd want to be spoolin thosse suckers with AvGas in them!! :shock: :shock:

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If the FM says you can burn diesel shouldnt that be enough? As long as you burn it according to the FM (mixing tanks half jet half deisel or half jet half Av, whatever the manual states) I would think that would be fine.

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I agree with what everyone has said about the manuals and the time allowed between overhauls.And mister Vibe I know that you allready know this as well.So my question to you is that if you know it will burn,and someone is trying to blow your *** off,do you really care what your burning???????????????


Hope your having fun,stay safe

Cheers Mini..

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T rex --------not all diesel fuel has sulpur in it. Truckers can buy it with or without. Ignition point on Jet-A is approximately 629C and Jet-B about 100C lower. Plain old diesel has a lot more oil in it and a lower ignition point than either of the other two. The oil in the diesel fuel starts to make the fuel gel at temps below 10C and then the fuel has to be thinned out with Varsol or some commercially-made anti-gelling product. I've seen the power turbine blades at Standard Aero that came from an engines that burned either Avgas or straight diesel for too long and it ain't pretty.......nice tan-coloured blades.

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Thanks for the replies fellas. I was just trying to satisfy my curiousity.


I remember that it says right in some flight manuals that you can burn some fuels for a certain period of time between overhauls. However, in the 212 manual it doesn't state any time limit whatsoever (that I can find). I didn't read what the M & O Manual said myself but I've been told it is simply allowed. That's why I was wondering if there were any other reg's I should be aware of.




P.S. And MINI, good God... if they start shooting I'll be putting straight vodka in the stove!!! If I can find any... it's a dry camp...:)

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