You can download it from here (it is in the katix.org gforge svn):
RangeCalculator.ods
Some calculated results:
Target range = 1500 nm
Fuel consumption = 31.5 liters/h (2 x Rotax 912ULS, with economy cruise power)
[kts] [h] [l] [kg]Speed Endurance required Fuel liters Fuel weight100 15 472.47 335.45110 13.64 429.52 304.96120 12.5 393.73 279.55130 11.54 363.44 258.04140 10.71 337.48 239.61150 10 314.98 223.64160 9.38 295.29 209.66170 8.82 277.92 197.33180 8.33 262.48 186.36190 7.89 248.67 176.56200 7.5 236.24 167.73210 7.14 224.99 159.74220 6.82 214.76 152.48230 6.52 205.42 145.85240 6.25 196.86 139.77250 6 188.99 134.18260 5.77 181.72 129.02270 5.56 174.99 124.24280 5.36 168.74 119.81290 5.17 162.92 115.67
Nice calculator. That last line would really make us all happy. The question only is, if that could be achieved?
Have you estimated your total cruise drag and speed vs. weight (with fuel consumption)? Integraiting that should yield the total endurance. Easy to do with some loop in the pgm. Just one have to make sure that the plane stays in the laminar bucket (if any).