LN400

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About LN400

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  1. I'll just add, by having the sats in a lower orbit, you can get away with shorter range antennas for local network which consume less power. Combined with a shorter time on the planet's night side, it means you need fewer/smaller -> cheaper and lighter battery packs, making the overall launch cheaper which is always nice in career mode.
  2. Well, the modules for the Mun (legs, not tracks or wheels on these modules) operation is already orbiting Mun ready to land as soon as the rovers on the ground have found the highest ore concentration. Already on the ground are 2 fuel tanks on legs and a science probe also on legs. They were hooked up using winches and there was no hint of trouble then. I will land the mining modules soon and find out if Mun is generally more Kraken free than Kerbin which apparenly is where Kraken and its mom live.
  3. THe bit I bolded there is a major pain in the neck. I have a contract for a Mun surface base for 12 kerbals, 7000 units of LF, 5000 units of ore and the whole bleedin monstrosity has to be on wheels, as per contract. There is no way I will get that in one piece from Kerbin to Mun even with empty fuel/ore tanks.
  4. As for auto struts the answer is no. In fact that was the reason I went for the KF wheels as they don't have forced auto struts. As for not understanding the behaviour, that makes 2 of us. It is weirder than weird Al and it baffles me a great deal not to mention troubles me as a failed design of a mining installation will be quite damaging to my career mode bank account.
  5. First, I could post this in the KF mod thread but I figured some replies here might be outside that thread's scope so here goes: Now, for some issues I have that might have a workaround or a solution (this is where I hope you guys will chime in with your experiences): I use the mod KerbalFoundries for the wheels and tracks. They work... kind of BUT tests on Kerbin had the Kraken rear its ugly head: If a kerbal so much as came near the KF wheels, it would rocket left and right up and down like crazy, stretching out like mad spaghetti before exploding in a puff of dust. Weird thing is, the KF tracks work like a dream on Mun where the Kerbals can climb the tracks and all is fine and dandy, Kraken sound asleep. I plan on a Minmus mining operation, big scale and the decision has been made to make it module based using winches to hook all the modules together. This to allow for expansions for more drills or power or battery banks, fuel tanks, cooling etc etc etc. The drill unit will be a quad drill with large ore tanks on the same unit. This unit I really would like on tracks since it might need to move around. One design has some mamoth sized tracks and the whole thing has a dry mass of around 40 tons. The fuel tank unit that will hook up to this is also around 40 tons. Refinery, PSU, coolers and battery banks will all be separate modules but again, tests on Kerbin had all the light weight modules go bananas as soon as they hooked up to the heavies, jumping around until they tore themselves apart and exploded. I have no idea but I suspect the CoM calculation is not coping well with the winch but at the same time,, I do keep in mind how the KF tracks changed behaviour as described above as soon as they landed on Mun. So, any inputs/ideas on how I should go about it? Any of you ever had similar issues? For a wheeled/tracked, module based operation, how would you go about it? Any tips or suggestions on mobile mining/refinery operations on other bodies than Kerbin?
  6. I never bother with geosynchronous orbits for my commsat hub or any other comm sat. I just don't see the point. As you point out, as long as their periods are the same, it still works just fine. My standard setup is 800-900 km for all comm satellites around Kerbin, 4 hub sats at 840 km, Mun and Minus get 2 at say 835 km, Moho/Eve 2 at 830 etc etc untl I replace all with 4 sats with full comm capabilities for all planets + 1 direct link to the active ship + 3 for a link to a Sun hub late in the game for link to planets in the Suns comm shadow from Kerbin. None of these sats ever go geosynchronous. (Reason for these altitude bands is I don't have to think about where I can place other ships and sats with no risk of collisions. I use the same idea for pretty much the entire altitude band down to 70km, each 1000m or so meter is assigned a non-debatable purpose. Tourists/parts tests/one orbit trips etc get 71km, rescues are typically between 75 and 95km). Departure is 100km, return to LKO 101km etc etc).
  7. If two or more really, REALLY important events are to happen, they WILL, invariably, happen at the exact same time. No way around that one.
  8. Making A Manoeuvre Burn Using Two Stages?

    Keep in mind that burn time is a function of not only delta v but also acceleration. Delta v requirements will be the same for any engine but the acceleration will not. To find the starting acceleration, take the thrust that the engine produces, and divide by mass*9.81 (close to Kerbin's surface, other values entirely on and around other bodies). Now take the delta v you need and divide by the acceleration you just calculated to get burn time in seconds (actual burn time will be lower as the spent fuel means less mass and higher acceleration but for ballpark figures it'll work). So: Know or calculate how much dv the first of the two stages will give you and for how long the engine will burn before the fuel is spent. Calculate the burn time for the 2nd of the two stages to give you the remaining m/s. Total burn time will be the sum of these 2 burn times. Add then the time you need for a clean separation.
  9. Bewing is right. If you use a mod that gives you detailed flight info, like KER, and some auto throttle capable mod like RT then it is quite possible to have the orbital period match to tenths of a millisecond.
  10. Favorite/Must-have mods

    Hah! I suppose that explains why I thought the mod had had a name change. I was missing the circularize feature and lo and behold, it was there in the other mod all along, huh? I guess I will have to try that then.
  11. Favorite/Must-have mods

    My bad, I guess I'm tired. Yeah I meant Precice Node. The memory thing has always been a bit of a blighter on this computer and with SCANSat I don't have many spare bits of RAM left.
  12. Using my equations, for the T45 engine, TWR = 1.5 and dv first stage = 1700 m/s ASL value, I do get a wet to fuel ratio of pretty close to 2, like really close down to the 4th decimal. For the 2nd stage using a 909, TWR = 1.79, dv = 1700 m/s vacuum value, I get a wet to fuel ratio of 2.53-ish to maintain the wet mass, TWR and dv for the first stage. To punch in the figures: I want a starting TWR of 1.5 and a first stage dv of 1700 m/s ASL. At sea level, the T45 has the following specs: Thrust: 167.969 kN, Isp 250s. That gives a starting wet mass of the whole tabernacle of 11.4187 t. To get a dv of 1700, I need a wet to dry ratio of 2 + a tiiiny bit which gives a dry mass of 5.7079 t which in turn gives me the fuel mass of 5,7108 meaning 514,0 units of LF and 628.2 units of LO. Decoupler, engine, 4 fins, fuel and the tank has a combined mass of 8.009 t which means it can carry 3.4097 t. That will be the wet mass for the 2nd stage. The 909 has the vacuum specs of 60 kN, 345s. To get 1700 m/s, I need 1.3467 t of fuel. Decoupler, engine, fuel and tank has a combined mass of 2.058t which gives the payload mass of 1.3517t or about 11.8% of the full mass of the entire thing.
  13. This is one reason I use procedural tanks and not the standard sized ones. It does mean the rocket won't be the cheapest possible but here the entire project is to break up the monotony, and have some fun with maths while I'm at it. I have the door open for SRB for those extra kilonewtons and m/s but since I need to learn a lot here, I think I'll keep it simple until I get the hang of these single engine rockets. This is quite an interesting bit of info there. I'll have to play around with that and see how that goes.
  14. What did you do in KSP today?

    Been going through my 1.3.0 mod soup and realized it is a royal nightmare to go through finding out if all of them have been updated to 1.3.1.
  15. Favorite/Must-have mods

    The most essential: Kerbal Alarm Clock for without it I shall not go to space or anywhere else today. Now for other must haves: KER KIS/KAS SCANSat RemoteTech MRS SpaceY KW Rocketry Procedural Fairings Procedural Tanks Infernal Robotics Precice Maneuver but alas, I can not run it as it gobbles up whatever memory SCANSat has left over and throws me out to desktop.