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About ArcFurnace

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  1. You could turn the resistojet into a high-ISP RCS port. Sadly linear only since multi-nozzle bipropellant RCS doesn't work in stock, but the current model only has one nozzle anyway. You might have to shrink it a bit, of course. EDIT: Found an issue, the mass ratio of the FS-L 0.625m LFO tanks is off. The stock fuel tanks have all been normalized to have a mass ratio of 9 (8 tons fuel:1 ton tank). The FS-L tanks have a mass ratio of 81 (80 tons fuel:1 ton tank) - e.g. the FS-L50 carries 1.2 tons of fuel with a tank mass of 0.015 tons, compared to the FL-T200 that carries 1 ton of fuel with
  2. That's looking pretty good. I would also add a comparison with the O-10 "Puff", which is 0.0 Ec/s, 250s, 20 kN, 0.09t, TWR 22.65, Precision Propulsion (t5). Clearly the high-TWR, low-ISP option for monopropellant.
  3. I'm not sure if you can really call the Project Pluto design a "jet" in the sense of a manned aircraft useful for anything other than destruction. It was unmanned, had no radiation shielding at all and had radioactive reactor-core dust as part of the exhaust stream, and I doubt you can eliminate those without reducing the performance substantially. Radiation shielding to keep crew and passengers healthy is heavy, and if you don't want bits of the reactor core coming out the exhaust you have to run it at lower temperatures and/or without supersonic airflow through the heat exchanger (making i
  4. Acceleration can be measured by an accelerometer. Taking the time integral of the acceleration gets you the change in velocity, although you have to be careful (if the accelerometer is off by a little, integrating over time will result in increasing levels of error in your measured velocity). See also inertial navigation system, which is a more detailed discussion of that procedure. A star tracker can give you your attitude (the direction you're facing), although I'm not sure if it's possible to get velocity from those. If you have access to a ground station, you can send radio signals bac
  5. Also, specify which dev build you're using, by version number or similar - "most recent" works at the time you post it, but it's possible that Ferram could push another update before he sees your report, in which case confusion might result if you don't clearly specify the version.
  6. I actually couldn't find numbers for Merlin 1D-Vacuum sea level ISP anywhere, presumably because nobody bothered to calculate them (as it would never be used). I did find this webpage, which states that while the Merlin 1D has a chamber pressure of 97 bar (9.7 MPa) and an expansion ratio of 16, the Merlin 1D-Vacuum has the same chamber pressure and an expansion ratio of over 117! Even more annoyingly, I couldn't find equations that would let me take the chamber pressure and expansion ratio and calculate the exhaust pressure at the nozzle, but I bet it's a lot lower than 1 atm, which would in
  7. Basically, with the stock system, a certain amount of heat flux (from the shock compression plasma) is applied to parts. However, in the stock system a single part is modeled as having a single temperature throughout that part, and the entire mass of the part contributes to its thermal mass (how much energy you need to add to raise its temperature by a certain amount). This means that for, say, a big heavy fuel tank, it takes quite a lot of heat to heat it up to the point where it explodes from overheating. This isn't really realistic. The superheated air is only touching the very outside
  8. So, reading Claw's post there, it seems the major reason why the air feels so "soupy" is that pointy shapes (nosecones and such) that OUGHT to cut through the air easily are actually modeled as being much more drag-inducing - and since the majority of drag comes from the front face of the craft, this makes drag seem excessive overall. My other comment is that, currently, reentry heating doesn't do much due to craft slowing down rapidly enough that nothing overheats (I had a craft turn out to be reentry-unstable and flip so that all the parachutes were facing forward, but it made it through t
  9. I agree that electric propellers would be nice. Would either need a workaround or an adjustment to the stock engine module, though- the current version requires an ISP value and at least one propellant that has mass (ElectricCharge does not), which is why you have things like the Firespitter electric propellers generating "FSCoolant" from ElectricCharge and then using that inside the engine module. Squad being in control of the game's code, they are in the best position of anyone to make this workable without using such a workaround.
  10. Material is the most relevant for maxTemp values, shape could affect heat loading during reentry but would not really alter maxTemp. Very few materials meet the dual criteria of (a) structural strength at high temperatures and ( low weight. The Space Shuttle thermal protection system gives several examples of high-temperature materials. One of the highest real-world values is the reinforced carbon-carbon leading edges on the Shuttle, which are structural and rated for up to 1,500 °C, although RCC can be very brittle. RCC may even be able to go higher than 1,500 °C. A lower-temperatur
  11. You seem to be conflating "procedural fairings" (non-predefined-shape fairings) with Procedural Fairings (the mod). In Procedural Fairings you just place a fairing base and a fairing panel, and it automagically reshapes itself to fit the payload- am I right that you feel that this is "cheating"/"too easy" since it requires no effort from the player to ensure that the payload fits in the fairing? The actual description of how the fairings work by HarvesteR seems to imply that this is not the case for their implementation. I see nothing in there about automatic fairing shaping, and several t
  12. That is looking pretty good to me, Nertea! I like that it now has a separate niche of wide-load (plenty of room for extra surface-mounted bits on the sides of a 2.5m fuselage) or rover deployment with that flat bottom and the tail ramp, making it nicely distinct from the stock Mk3, which is a bit more of a snug fit on 2.5m cargo and can't really do rovers (outside of maybe dropping them from an inverted cargo bay).
  13. So when you say "Mach effects," do you mean the visual effects (similar to what we already get when moving at high speeds at low altitudes), or a sudden increase in drag as you approach the sound barrier?
  14. Yes, precisely. The one that tells you part count/mass. It's in the AppLauncher (the stock toolbar), so it's an app.
  15. If that's what is supposed to happen, then something's bugged, because pressing Launch to Rendezvous doesn't update the launch inclination for me (tried this multiple times). It can still manage a decent intercept even with the wrong inclination. Launch into Plane of Target works perfectly, automatically updating the inclination of the launch autopilot to match the target and correctly timing the launch. This is 0.90 KSP with Mechjeb dev#393, no other mods installed. Reproduction steps (at least for me) are basically "have a target craft in an inclined orbit, manually set the launch autopi
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