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Let me start with the following disclamer. The results I present are for an ideal ship weighing approximately 335 t with 39t of fuel (Xenon or Argon). The ship was designed to shuttle 200t to mars and bring 20t back. The fuel that is provided is ideal fuel and assumes that burns are instantaneous. In reality more fuel would need to be brought along. The drive is assumed to have a nuclear powersupply, no such power supply exists AND if it did the cooling systems for the power supply would be much greater in mass than the mass provided for engines, power-supply, and radiative cooling. The vessel produces in excess of 0.0105 acceleration and has a total dV in the 8.7 km/sec range. The first set up assumes that the burn angle occurs around the periapsis of an opposing exit vector. So if a burn span is 270' then the burn begins 45' after the exit vector and continues until 45' bfore the exit vector, resting as it travels through the apoapsis. The first set up gets the ship to Earths average hill sphere with zero velocity relative to the Earth. SpanBurn TBurn (sec)(cumm.) T (to escape) Dv (m/s) Waste(m/s) 360 ' = 2π 604413 >7 days 6633 3422 270 = 3π/2 524607 >7 days 5726 2514 240 = 4π/3 452699 >13 days 4917 1705 180 = π 364657 >60 days 3937 725 120 = 2π/3 324279 >200 days 3491 280 90 = π/2 313283 >400 days 3370 159 60 = π/3 306224 ~1000 days 3293 81 Burning to Mars. Adding the 6471769 J/kg required to reach Mars at its apogee. SpanBurn TBurn (sec)(cumm.) T (to escape) Dv (m/s) Waste(m/s) 360 800005 >9 days 8902 5018 270 719818 >8 days 7964 4080 240 634915 >13 days 6863 3099 180 527567 >60 days 5759 1875 120 491702 >200 days 5355 1471 90 483796 >400 days 5265 1381 60 476635 ~1000 days 5185 1301 Note that some waste in the final burn to mars is unavoidable, because once spefici orbital energy >=0 one cannot 'kick' past the periapsis and so once the final burn that has SME_>0 has also be a parto of the burn that goes to mars despite the fact that most of the burn occurs at low velocity (and thus low dE/dt during the burn). There are several ways to improve this. 1. Burn down 5 to 10' more than prograde to keep Pe low (from 270 to to 200) 2. On the last jump, jump to 270 and also burn down at 30' 3. Switch the ION drive to burn at a lower ISP and higher thrust. 4. Have an auxillary chemical based engine on board. The dV difference between escape, and mars intercept is only about 400 at burn from 6531 km and so a reasonably small fuel tank with powerful engine would suffice, the fuel tank can be ditched after the burn, it will go into a circumsolar orbit. Lessons to be learned: In a burn to Mars from Earth orbit, you do not want to use a spiral (360 burn span) orbit. It wastes both fuel and time. Since a Mars mission would be at least 90 days the loss of 5 days getting a better fuel economy is worth it. This means that blocking off 120' of the orbit as a no burn zone is a reasonable move. For a space tug that has no real cost of time except for capital cost of inventory. blocking the burn from a half to 2/3rds of the orbit is a reasonably good choice.

First off, let me just say that from a couple year ago when I first started building parts this group has come a l o n g w a y in terms of improvements. What I have done: We need however some just basic glossary of terms somewhere, and the term defined like raycasttransformed = (this is what it does, this is how to employ it). . . . . . alphabetized and stickied. It would be nice to see an index at the begin than a headed paragraph on each keyword. The KSP specific area that hung me up were these terms and thrustVectorTransformName, animationName, and raycastTransformName. Built a new, from scratch, ION drive complete with emmissive - would absolutely not have been possible without the tutorials. Built a new, from scratch, Solar panel (10 meters by 100 meters, no joke), extendable non tracking (on purpose) solar panel. - animation would not have been possible without tutorials and searches here Built from scratch a new set of lattice elements (including 5 meter long aluminun poles, corners, T, 30 angles, pole anchors. So here is the basic issue. Im trying to control the power input for my ion drive. So basically this is it, I want to burn 70 units of electricity a second (For my panels im equating a unit to a kilowatt, the ion drive needs to burn 70 units per 0.001 thrust the xenon gas used then needs to be used accordingly to the ISP which is 9000. How to do? Im not exactly sure how electric charge is managed in an ion engine.