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Retread

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Everything posted by Retread

  1. Actually, in this case, the prefix "geo-" is derived from the ancient Greek word for Kerbin, and, therefore, geostationary is quite correct. Any resemblance to the word "geostationary" referencing earth is coincidental.
  2. I feel like we're being punked by the author of the contract flavour text... Also, " There probably ain't much sound in space especially when travelling, since sound is pretty slow "waves". I feel like we should have a long talk, but I have no idea where to begin.
  3. I've seen this, too - only on the swept wings. I think it's a bug in the wings.
  4. The arrows you see are not the actual aerodynamic forces, just decoys to keep you occupied until the internet police arrives. Alerting them is what F12 actually does.
  5. I've never tried it, but I've heard lots of people using Seperatrons for this purpose.
  6. Great topic! I haven't seen much discussion of this before, and I've often wondered how others optimize landings. Theoretically, I believe the most efficient landing is essentially a gravity turn in reverse. All thrust takes place exactly retrograde, with the retrograde vector smoothly descending from horizontal to vertical as you burn, timing the burn so that your velocity relative to the surface reaches zero just as you touch down. In practice, the burn would need to be timed and throttled almost perfectly, or else you would reach zero velocity somewhere above the surface, requiring more dV to land, or below the surface, with obvious severe negative consequences. My landings are typically broken down into a deorbit phase and a descent phase. In the deorbit phase, my goal is to reduce my Pe a point low enough above the surface that I can begin the descent phase. I burn retrograde briefly at the beginning to lower my Pe, and then again shortly before the intended landing point to reduce my trajectory closer to vertical, beginning the descent. Because both burns are retrograde, I don't think there is too much inefficiency in the deorbit phase. During the descent phase, burns have two purposes - the first is to reduce my speed enough to land safely, the other to fine tune my landing location. Any dV spent fine tuning the location is going to be over and above that necessary to land, and this can be reduced by making the initial deorbit burn more accurate. Most dV is wasted because I try to give myself enough time to respond as the landing develops, limiting my vertical speed to something I'm comfortable with. Ideally, you would do a suicide burn as above. Since almost all of the dV losses happen during the descent phase, I try to minimize how long this phase is by bringing the Pe as close to the surface as possible during the initial deorbit burn. When landing on the Minmus flats, for example, I burn retrograde on the opposite side of the moon from my intended landing so that my Pe decreases from 20km to 3.5km, just enough to skim the mountains near the landing spot.
  7. Better yet, build only one satellite, with enough dV to reach both orbits.
  8. Could we see a picture of your craft? There's no reason what you're describing shouldn't work as expected.
  9. Once you're above 10km, friction losses are pretty minimal, despite the fireworks going on around your rocket. With the right rocket design, you can actually turn SAS right off, and let the rocket fly itself to space on a gravity turn, naturally following the prograde marker. It takes some practice adjusting your TWR in flight, but I do most of my launches without SAS now.
  10. I have a mining operation on Minmus at about 35° latitude, and use a tanker/rover to transfer fuel between it and an orbiting refuelling station. Here's a summary of my landing procedure. Note that the tanker starts in a 20km circular equatorial orbit. 1. On the opposite side of Minmus from the landing site, burn retrograde until the periapsis is about 3500m. This altitude varies on different bodies, I try to get as low as possible without creating a chance to impact a mountain range. Your periapsis should now be above the equator, directly south or north of the landing site. 2. Create a maneuver node halfway between apo- and periapsis, and plan for a normal or anti-normal burn that will bring your orbit directly over the landing site. Add sufficient retrograde to maintain the periapsis at the same height as before. Complete this burn, and your periapsis should now be directly over the landing site, although there's no need to be too exact. 3. Create a maneuver node about 10° before the landing site, and plan for a retrograde burn that leaves you intersecting the ground beyond the landing site. This will be your initial landing burn. 4. Create a second maneuver node between the landing site and inital landing burn, and plan for enough retrograde so that your orbit intersects the landing site. 5. As you get close to the initial landing burn, you may need to adjust where the burns are due to Minmus' rotation. The idea is to make the final burn so that the lander is coming down near vertically close to the landing site. 6. Execute both burns. You should now be close enough to the landing site to steer the lander in manually the rest of the way.
  11. I agree that the initial nudge has a great deal to do with how a gravity turn will turn out. You can control the rate at which your rocket tips towards the horizon to some degree with the throttle, however. As you ascend, keep a close eye on your TWR; you'll need a mod like mechjob or kerbal engineer for this. (They will also calculate your delta V for you). If you find the nose of the ship not dropping to the horizon fast enough, throttle back to reduce your TWR. If it is dropping too quickly, increase your throttle. This technique does not give you a huge amount of control, and will not overcome poor design decisions, but it does allow some control over the flight path.
  12. Two more tips: 1. If you need to make a plane change to match your target orbit, do it when you are as far from Kerbin as possible to minimize the required deltaV. In other words, raise your periapsis out to the ascending/descending node of the target orbit, and do a combined maneuver to raise your apoapsis and match planes at the same time. 2. Double check the direction of the target orbit before you launch, it's easy (for me, at least) to launch in the exact opposite direction you need to go.
  13. And yet I feel responsible for poor Lexie Kerman's death. It was my greed, more than anything, that did her in. It was supposed to be a simple mission; three kerbonauts and two tourists on a flag planting, experience gathering jaunt to Minmus, the first to use completely reusable equipment. All went well until the spaceplane from Kerblab returning them home had already touched down, when I noticed I had never collected science while flying low over the SPH. Out the hatch goes Lexie, only to fall off the ladder and -splat-. Gone. Sigh.
  14. And yet I had a Kerbal fall off a spaceplane - on the gorund - and die in a puff of smoke.
  15. I have Surface Pro 2, and while I've played KSP on it, I can't say it was a very enjoyable experience. The game runs OK on the lowest settings, but the small screen and cramped keyboard make it hard to see and control what's going on, even with a mouse.
  16. The most fool proof method I've found is this: 1. Match your target's orbit as closely as possible. At this stage, it doesn't matter how far out of phase the two vessels are. 2. At periapsis, burn prograde until you get a close intercept (which should also take place close to periapsis) 3. At intercept, burn retrograde to kill relative velocity, fine tuning as necessary to acchienve rendezvous. Think of it in terms of orbital periods. For example, both you and the target are in the same orbit, taking 1 hour for a complete circuit of Kerbin. If the target is 15 minutes behind you, you need to lengthen your orbit by 15 minutes in order to arrive at the same place at the same time next time around. If your target is ahead of you, you could also decrease your orbital period by making the initial burn retrograde. However, this is not possible in most cases because you will hit the atmosphere or the ground unless the target is very close.
  17. Maybe I didn't ask the question right, then. As far as I know, there are certain alignments between two planets that will allow for minimim dV transfers between them, usually referred to as launch or transfer windows. Are you saying that by allowing several orbits to elapse between escape from one planet and insertion to another, there's additional dV savings to be had?
  18. I can't help you with a mod that would show this, but I'm wondering why you would want to do it this way instead of just waiting for a transfer window.
  19. The wiki has orbital speeds for each planet (min/max), along with all the other orbital parameters. Here's a link to a fantastic delta-V map you can use for mission planning: http://forum.kerbalspaceprogram.com/threads/96985-1-0-4-WAC-s-Delta-V-Map-continued-2-2-(Aug-13th)-Swash-transition Wikipedia has a short article on orbital speed here, complete with equations: https://en.wikipedia.org/wiki/Orbital_speed
  20. I would tend to build and assemble a single ship in orbit, if for the simple reason that that is the only way to ensure they all arrive within a reasonable time period of each other. Plus, big ships are cooler. On the downside, they are more difficult to design, take a long time to assemble correctly in orbit, and are more difficult to fly because their size often makes them less stable and they require longer burn times. As for the science question, here's one time you get to have your cake and eat it, too. Processing science in the lab simply fuels up the lab's data store, which can then crank out science points. The data can still be returned to KSC for full value.
  21. I wonder if the water-drop-in-freefall thing has ever been done in a vaccum. Would a glob of water released into space truly just vaporize? Or would a solid, frozen "skin" of ice form, allowing the water inside to remain liquid for a time?
  22. Hyperedit it to the runway and recover it. No functional difference to using some kind of auto-pilot functionality.
  23. I don't think Minmus is slippery, per se, but the low gravity makes wheel contact tenuous, at best. I've noticed that my Minmus fuel transfer lander/rover (basically an orange tank with wheels and engines) works much better when loaded than when empty.
  24. The ONLY female kerbal? My save is populated almost entirely by female Kerbals, since that's all that seems to spawn for rescue missions.
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