"Theoretically", your x-cntry planning should include airports with diesel available, I think.
There is a lot of difference between diesel and Jet A and the Thielert engines are designed to burn Jet A----wouldn't try pump diesel until I checked factory specs thoroughly
Woah, so if i understand you right these diesel engines actually burn JetA and are just using the diesel type combustion principal?
Seems to be some misunderstanding going on here...
Diesel Engines don't neccessarily burn diesel fuel, it's a combustion process. Yes, the aviation diesel engines are designed to run on Jet A. However, any diesel engine will run on Jet A (which used to be called aviation kerosene).
It's not done this way anymore, but the flow for Jet A production used to be: oil ---> Diesel fuel --> Kerosene --> Jet A
The thing is, Jet A is a lot more highly refined than Diesel fuel. The modern diesel is probobly going to start getting a lot closer though with the change to ULSD (Ultra Low Sulfer Diesel). What this leads to is that you can generally run Jet A in a Diesel engine without any ill effects, but an engine designed specifically with Jet A in mind miight not like diesel fuel becuase it'll essentially be "dirtier."
There is a question with modern Jet A about whether any new additives will harm seals in an engine not designed for it, but that's just theory and I've never heard of anyone having problems if they ran Jet A in their fuel trucks or other diesel vehicles on the ramp.
However, turbine engines don't actually *need* Jet A either. In fact, they've had turbine engines running on anything from coal dust to powdered milk! The problem with these is that you have to set up the burner to burn whatever fuel if it is a different form (such as powder). We are allowed to run 100LL Avgas in our PT6s, although we are limited in how much power we are allowed to output with it (gasoline burns faster and hotter than Jet A or diesel fuel, gasoline tends to explode while diesel or jet fuel just tends to burn, this is why there have actually been instances of diesel fuel putting *out* fires because it actually isn't extremely easy to ignite like gasoline).
To further give you a headache, the first diesel engines didn't run on diesel fuel.