Wemb

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About Wemb

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  1. So, I've got a science station in orbit round the Mun, and a little probe-based lander going down and collecting Science. Rather than sending a capsule based lander up, If I get an engineer to attach a ladder using KAS, can I ride Bob down to the surface as a passenger to do a soil sample and leave a flag behind? Thanks
  2. The answer is not much , but it's probably more than you think - the reason being that while the mun has no atmosphere a very slow ascent with a TWR of near to one will not necessarily be less efficient than using a higher power engine since because there is no atmosphere, you don't need to do it quickly - BUT landing definitely is time bound - you need enough time to reduce horizontal speed and reduce vertical speed at the same time (in most scenarios), and you also need to time to spare and time to recover from unexpected mountains. For all I know (not much) this could be one of the reasons why it was beneficial for the real Lunar Module to use a separate lander and ascent stages (though there were plenty of other reasons, mostly weight and reliability issues, I bet, that were probably more important) Wemb
  3. Today I learned that with RemoteTech installed, a Solar eclipse just before you start re-entry is a very scary thing indeed. Wemb
  4. The straight up and turn left approach isn't a good idea, hardly ever - and while trying to do a perfect gravity turn is an 'advanced' technique, you should be able to manage a fair approximation. Instead of sticking to the prograde dead one when you get to ~45 deg at ~15km, I'd hold at a bit above your prograde on the rest of the journey. Keep an eye on the map view and cut your engines when your Ap gets out of the atmosphere (70km) and then coast with the engines off till you get to the Ap before lighting them up again to circularise. Hopefully this way you'll come up with a good compromise between a very flat trajectory at the apex of your flight, and a straight-up trajectory. You might find it helpful to put on KER or MJ so you can see your Ap and time to Ap during the flight. If you do this, after you get to ~45 deg at ~15km, try and aim to keep your ToA at about 45-sec to 1min, too much higher than that you may reach the Ap before your leave the atmosphere, too low and too low and you'll reach your Ap before you get a change to gain enough horizontal velocity. That should get you into orbit fairly smoothly. Wemb
  5. One thing which might help illuminate why logarithms are a thing at all is that as well as being incredibly fundamental in calculations involving rates of change growth - they are also tremendously useful in simplifying manual arithmetic - and this was why they were first developed and investigated. Imagine you want to multiple two large numbers togther - 4324924823 x 6575676575 - this is a farily horrible and time consuming job if you don't have a calculator or computer (or, if you existed before they were invented). However, one of the rules that govern how logarithms work is that log (x) + log(y) = log (xy) So that if you had a compiled table of logs and their inverses, you could easily perform otherwise very long-winded mulitplications by simply looking up a couple of numbers from a table, adding them together and looking up the result in a second table. And, if you're using logs to the base 10, rather than the natural log, you don't have to worry about the decimal places till to the end, and that's also a trivial exercise in adding. Slide rules allow you do to the simialr, but in a somewhat more flexible way. This facility is why the exams I did in the late1980s and early 1990's still had printed log tables in the back of the formula book for those without calculators, or where calculators were not allowed. Wemb.
  6. This is what I love about this game and this community - you just don't get lessons on arithmetic like this on Call of Duty forums. Wemb
  7. Sure - and it's about the simplest thing you can design, since it'll never go near an atmosphere so you don't need to worry about aerodynamics and the TWR is vastly less of a consideration. Just pop a probe core with a docking port, a solar panel (probably), and some RCS - probably a lot if it's a fuel tanker - on the tank of your choice and you're done. Main consideration will be what engine you choose - obviously, a high vacuum ISP engine is best, but don't worry about the TWR too much - as long as it can accelerate/decelerate quickly enough to do the necessary rendezvous and docking manoeuvres you'll be okay. If you want a truly massive tanker with the highest possible fraction of fuel capacity to weight, you could, in theory, have a very low TWR and use tugs based at the station to do the capture and docking, though this may be more trouble than it's worth. Getting it into space, is an exercise for the OP - but note you can empty a fuel tank in the VAB if you don't need to carry it to space loaded. Wemb
  8. I'm struggling in my head to decide if the rotation of Kerbin needs to be taken into account with regard to what the navball is 'pointing at'. You'd see different results if it's orbit vs. surface mode, no? Wemb
  9. This - there's nothing stopping you flying two missions - one to stop him crashing and the other to bring him home. Wemb
  10. My view? Same as Chris Kraft's mostly... See this clip from 'From the Earth to the Moon' - you're yet to do docking and rendevouz, get to grips with the dV maps and build your rockets to requirements so you don't run out of fuel after landing, and keep on doing it over and over till it's easy. Then head for the planets :-) Good luck, and godspeed. https://www.youtube.com/watch?v=xZVe8N5uICI Wemb
  11. One thing I really want to explore is some properly automated launches that don't rely on MJ. I want, at some point, to fly a missions to dock at my orbiting station and do it entirely from within the IVA view with the games main GUI turned off via the F2 key. It should be possible to do this using MJ (for it's SmartASS) coupled to the RasterPropMonitor MFD displays. The one element that's missing is a sensible way to launch this. I could wing it from the navball, but my goal will be to do the launch with kOS. kOS isn't something I've remotely looked into yet, but it sounds interesting and would add a whole new interface to the game, rather than extending the game outwards with more planets, it'd provide me with an entirely new mechanic, and set of challenges, for handing even the simple stuff. Wemb
  12. Not in the strictest sense, no. The problem comes if you get any sort of off-axis translation when you're trying to dock - and if your vessels are moving in circles round planets, this is quite likely. Correcting for this with a reaction wheel and main engine isn't so much difficult as very time consuming and unwieldy as it requires you rotate the entire ship in the opposite direction of the drift and then burn to correct and then turn back to the target. Attempting to do this when you're 10 seconds from a docking is almost certain to be disastrous in some way. Wemb
  13. You'll eventually hit other issues with certificates as well as games that start to use newer frameworks and runtimes - I'm afraid it really is time to consider changing to or upgrade your OS to something supported. Wemb
  14. As the others have said - It's designed (invented) for fine control of translation and rotation that generally cannot be done, or be done easily, with the main engine. It's principal application is for assisting with docking where extremely accurate control of attitude and velocity is vital, but it can be used to help in many other areas such as landing, launch stability, or even to replace a main engine if needed. This is a brilliant video of the Soyuz TMA-19M mission to the ISS last year where the automatic docking failed and had to be done manually by the commander. you can see at ~3:50 onward the RCS thrusters on the soyuz capsule firing to help keep the capsule aligned in the right direction for docking, and at 4:35 firing to reverse the capsule and back away from the ISS. Wemb
  15. What he said. The only way you could have something that looks like an exception would be if the planet had it's centre of gravity somewhere other than at it's geometric centre and while that happens in a tiny degree IRL, I don't believe it happens in KSP. Wemb