gunradd

My Feedback: (9)

Yes Kelly same mix. 1qt per 5 gallons

Kelly Rohrbach

My Feedback: (1)

Perfect, thank you Sir!!!

rcjetsaok

My Feedback: (7)

Well, Jet-A only for me... If I wanted something to run on diesel it would have 18 wheels, a 40 channel C.B. radio with twin antenna's, and chrome naked lady's on the mud flaps. It's like guy's using 2-stroke oil for their turbines... If I was gonna do that I would have a 90 mph bass boat that would put bugs in your teeth !! This hobby is AVIATION gentlemen.... Use the aviation stuff !! If your gonna use that other stuff, go drive a truck, go fish'in, or weed-eat your yard !!!
Ya'll are killing me !!!

10-10 on the side,
Danno

Hydro Junkie

I see people mentioning "biofuel". This was experimented with in the turbine powered unlimited hydroplanes around 10 years ago. The engine use for these tests was a Lycoming T55-L7C helicopter engine, the same as used in the H-46 and H-47 heavy lift helicopters used by the US military back in the 60s through 90s. Anyway, using one blend, using fuel derived from peanuts and peanut plants, the boat in question actually set the high qualifying speed in Seattle when compared to boats burning Jet A, though it did leave the air smelling like peanuts. Now, this is all fine and good, if none of the people in the area are allergic to nuts. The next test, in 2009, they used a blend based on oil extracted from the camelina plant and found the results to be similarly fast and without the issue of nut sensitivities. While qualifying first may not sound like a big deal, the boat used was built in 1995 and outran boats that were brand new and state of the art. The only advantage the boat had was it was driven, in both tests, by 11 time APBA Gold Cup Champion Chip Hanauer

stevekott

My last plane was a Piper Meridian with a Pratt-Whitney PT-6 Turboprop. And it was a 'real' aircraft. Guess what? It was certified to run on Jet-A or Diesel. It was even certified to run on 100 LL Avgas for up to 100 hours!

Turbines by nature are a LOT more tolerant of different fuels than a piston engine.

The biggest difference between K1 kerosene and Jet-A is the amount of sulphur (smell) it is allowed to contain. K1 is just a more refined product. Jet-A is allowed to be more 'crude' because it is designed to burn in an outdoor environment where the smell is not so much an issue. There are no performance advantages of Jet-A over K1 Kerosene and it even has a lower energy content than Diesel.

Kelly Rohrbach

My Feedback: (1)

What started my quest to find the answer is our local FBO is in danger of being shut down because of idiots that buy a home next to a city airport and then ***** about the noise of full scale aircraft flying above their house. The world is full of jack wagons.
This could make it a bit more challenging as we would have to get Jet A from our local larger International Airport, not that we can't but just more hoops to jump though.
I always knew Jet-A /Diesel/Kero are about the same drink, just wanted good proof that its a non issue before there is one and I hear "What the heck were you thinking"

cmp3cantrj

That is just a name slapped on at the pumps that means "this Diesel has our Special additives for easy starts" Less smoke, Cold weather etc. The diesel without this extra stuff that has no importance to us at all..... is ALL IDENTICAL no matter who refines it!!

Actually those special additives DO make a difference. We had a guy from Rolls-Royce Germany at the latest GTBA meeting and they are using turbine powered drones professionally for surveying inside large buildings and they have to use premium diesel to avoid hydocarbon residues.

The additives promote complete combustion - which is of value to us.

cmp3cantrj

More likely your flying is erratic!

A change from 172-> 197 mph requires a 31% thrust increase!

There is just no way such a change could result from a fuel change so I just don't believe you!

I'm sure if such a thing was possible it would have been detected by the turbine manufacturers and the guys who have tested turbines for RCJI!

The US service agents for Kingtech suggest a 5% performance increase - which is in line with the slightly high volumetric energy density of diesel - assuming that you leave the pump settings unchanged and allow the rpm to rise.

Of course if you adjust the engine to the same maximum rpm then there can be no difference because the thrust is governed by the mass flow and the exhaust velocity only. Both of these are directly linked to the rotor speed. Fuel has no direct role. This is all just basic physics - and there is no way around it.

If the Kingtech result is reporting improved fuel consumption rather than thrust then of course that is just down to the improved volumetric energy density. However diesel is heavier so the mass energy density will not see the same advantage.

The only kind of advantage that might be genuine would be a lower EGT - however even that is really down to the detailed design of the combustion chamber. i.e. this is just a matching issue and not an absolute - a different engine will show a different result!

HarryC

My Feedback: (1)

A lot of us use 28-second heating oil which is widely available and is half the price of diesel in the UK. I believe diesel is 35-second, which is a thicker viscosity. Oil companies' data sheets show that 28-second heating oil, Jet A1, kerosene, paraffin, etc are essentially the same thing, such as this one from Gulf and you can find the same from Conoco and others http://gulfoil.co.uk/content/uploads...sds_rev_01.pdf

A heating oil distributor near to me has a heating oil pump like a petrol pump at their yard, drive up and fill up jerry cans for just over 50 pence per litre (diesel currently around 110p/litre). Have been using it for a few years.

cmp3cantrj

Yes - ultimately it is a matter of local convenience. It just happens that my source of Jet A1 is on the same site as one of my flying fields and sells the stuff straight from the lorry at a price which varies with the oil price - but is currently 50p a litre.

A local garage sells kerosene at around £25 for 25 litres - - but comes with a free fuel container that might otherwise cost £11-£12 so I have used that a couple of times!

Ad Clark III

My Feedback: (8)

A couple of buddies and I were talking this morning, 126,000 rpm is the same thrust whether it's running on diesel, jet A, or strawberry jam. Of course pump voltages, egt, and mileage would likely change.

Pretty funny Danno, 10-10 on the side....Lol

josecilurzo

This is the rear bearing that Jetcat Brazil, was changed in my P80se, after 40hs of run time.

Henke Torphammar

Sure! I agree. The problem with our small turbines are that some are really ****(s h i t) in terms of engineering for good evaporation and such. Those are sensitive to different fuels. In general the older the engine, the less refined it is. The older Jetcats are simply not in line with modern cheap engines, even though they did a great thing back in the days.

Desert Fox 1

josecilurzo,

And you were burning Jet-A, Kero, or Diesel?

Cheers!
Desert Fox 1

Kelly Rohrbach

My Feedback: (1)

And in what condition is it in, unfortunately the picture does not tell the whole story, but thank you for sharing. Its a good discussion anyway and good input for those of us that have only used Jet-A. As long as the engine builders have no issues using either and the owners aren't having issues in the field then it sounds like a win win.

josecilurzo

Desert and Kelly,
i. Use diesel, mix jeta1, today 80%/20%, sometimes 100% diesel, this bearing are very smooth, and, clean, after 40hs, jetcat brazil was told me that the bearing could be using at least 10 hs more.

jose