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ground effect
24th Apr 2005, 00:06
So based on a little background reading I have found that although not preferable it is possible (eg in an emergency situation?) to run a turbine engine on a `wide cut` fuel like avgas 100LL SG .72 ....but the result... incorrect fuel metering, reduced performance, decreased range, over temp and over speed.

What if we reverse the senerio. Is it hypothetically possible to run a piston engine aviation machine on turbine fuel SG.80 ?? Are the `anti knock`qualities inadequate, how would it perform, what damage would result.

?????

IHL
24th Apr 2005, 02:41
There are numerous accident reports in where a piston aircraft was incorrectly fuelled with TURBINE fuel. The aircraft tend to run fine because of dilution and avgas in the fuel lines until after takeoff at which time the aircraft usually crashes or requires an immediate emergency landing with an- an change there after.

Turbine fuel CANNOT be used in a piston aircraft !

Gomer Pylot
24th Apr 2005, 20:08
Internal combustion piston engines do not run on kerosene. It just isn't volatile enough. They won't run on diesel, either. A turbine engine, because of the way it works, will run using almost anything from diesel to gasoline, but it's not something you want to do with any regularity. A piston, OTOH, should only be operated using the specific fuel grade recommended by the engine manufacturer. Turbines and pistons work very differently.

ShyTorque
24th Apr 2005, 20:50
>Internal combustion piston engines do not run on kerosene. It just isn't volatile enough. They won't run on diesel, either.<

I think you must mean spark ignition engines because Diesels ARE internal combustion piston engines....?

The problem with kero isn't so much a lack of volatility BUT the octane rating of it is very low, hence it being possible to ignite it by cylinder compression in a diesel engine, as in the modern aero engines. With fuel injection, it is forcibly made into a spray / vapourised in any event.

I learned to drive on a 1950s Ferguson tractor that had a two chamber fuel tank. The engine was started on petrol (gasoline) and was switched to paraffin (kerosene) once it warmed up. It could burn kero without drama because the compression ratio was very low, so it didn't knock.

NickLappos
24th Apr 2005, 23:51
ground effect,

Let's not start another urban myth here. For the record, turbines burn almost anything that is clean and hydrocarbon, generally without the ill effects that you list. The biggest problem that turbines experience when they burn gasoline is lead deposits on the hot section, which limits the time you should burn the gas. Metering, stall protection, temperatures are all very well controlled with different fuels in a turbine. Starts have to be manually controlled, generally but performance is unaffected, and the range might be less only because less fuel mass fits in the gas tank, and for no other reason.

Giovanni Cento Nove
25th Apr 2005, 06:04
Centurion (http://www.centurion-engines.com/)

SMA Engines (http://www.smaengines.com/products_homepage.htm)

Both pistons, both burn JET and both certified!!

As for running a turbine on Avgas - I have had to do it once and never noticed any difference. As Nick says it's the lead deposits which limit the time period.