thats a tight squeeze leaving only a hundred miles ( 20 minutes?? ) worth of gas.. However, if I were to do it, I would after takeoff climb to 18000, set the power to about 66 percent and the pitch to cruise. However, let me qualify here.. I'm first and foremost an engineer, not a pilot. My work uses hard data extrapolated from the curves, dimensions, weight and engine data for any given plane.. Engineers typically dont need to know anything about flying, and as much as I would sometimes like to think otherwise, i'm afraid i'm one of them. You see, over the last year, i have been completely inside a P-61, and have accumulated well over a thousand hours flying it.. For that plane its a no brainer. Set the MP to 30 inch and th rpms to 2450, and you can make it to hnl with the external tanks loaded. But the spartan is a turbine. you dont set MP.. You dont set RPMs and at that point, my understanding breaks down. However I would still recommend 66% throttle,as if it has a cruise setting on the pitch adjust it for that.. Perhaps someone with more knowledge of Jets and turbines could answer this better..
Pam