Empiro

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About Empiro

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  1. This was what I did when I was starting out with docking, but once you learn how to use the navball, the navball is even easier and faster. On the navball, the RCS translation keys always behave exactly the same, regardless of how you've set up your camera.
  2. The two biggest pieces of advice I can give to the docking itself: Use the Navball. When I dock nowadays, the only time I look away from the navball is to look at the distance to my target. Learn what all the symbols mean and how your translational RCS (IJLK keys) affects your velocity marker, and rely on the Navball to dock. Learn how to point docking ports to each other by switching ships, and using the "control from here" functionality. This makes it so that you don't need to worry about flying around your target. You just need to point right at it.
  3. Unfortunately, I don't really think there's a good way to balance the RAPIER for use in career. If you're at the end of the tech tree (or close to it), then you've already spent millions to upgrade the science building to maximum, and various other buildings probably to at least level 2. That means that you've managed to earn all that money without using reusable SSTOs. Once you do get the tech for SSTOs what do you really need to make money for? Other than for the fun/challenge, there's really no need (no different than reusable SSTOs in Science/Sandbox modes)
  4. The nice thing about the round pods are that they have a built-in heat shield and decoupler, which saves on a decent amount of weight. Two things to watch out for is that the 3-crew version weighs so much that a single mk16 parachute may not slow it down enough. In addition, the heat shield and heat resistance on the pod is weak, and probably won't survive re-entry from the Mun and beyond, depending on your re-entry difficulty.
  5. Also, efficient planning is a big part of getting where you want to go with a reasonable sized rocket too, especially if you want to make multiple stops.
  6. You definitely shouldn't circularize at Jool or Eve if you're trying to get into orbit around around a far-away moon like Pol or Gilly, but I suspect that isn't what you meant either. I assume that you're actually talking about a course where (assuming you're in the right inclination already), you burn close to Jool just enough such that your AP intersects Pol's orbit. You'll eventually encounter Pol at your AP and can capture. Whether or not that saves Delta-V compared to capturing directly at Pol depends on a lot of factors. The general intuition is that by capturing close to Jool, you're taking maximum advantage of the Oberth effect since you're moving so fast close to Jool. It's easy to burn off the excess orbital energy you had when entering Jool. However, the cost is that you then have to raise your PE to match Pol's. It's similar to the tradeoff between a Hohmann Transfer versus a Bi-Elliptic. I haven't done the math, but I suspect that Eve and Kerbin are close enough that there's probably some savings in capturing at Gilly directly. However, Jool is far enough (and massive enough) such that I think it's still probably better to burn close to Jool. The optimum also can change if the moon is very massive, since you can take advantage of the Oberth effect there too, but both Pol and Gilly are small enough that I don't think it makes much of a difference here.
  7. It's true the ISP sucks, but again, remember that it's a specialized engine designed for an SSTO spaceplane in stock Kerbin. For most ascent profiles, you only need around 1600 m/s delta-V to get into orbit, do some maneuvers, and then land. The ISP doesn't matter too much in that realm. If I want to go somewhere farther, I'd use use a cargo SSTO powered by Rapiers to get into orbit, and then deploy a craft equipped with very efficient vacuum engines. That way, you don't haul unnecessary engines and wings around.
  8. Docking has two parts, the rendevous where you get close to each other, and the actual docking. Rendevous is not too hard, but docking a craft to a station that can't rotate is pretty difficult until you practice a lot. For rendevous, If they're in the same orbit then they'll stay the same distance from each other. How far are the two crafts from one another? If it's not too far (< 20km), select the other target in the Map, switch the NavBall to Target, and burn toward the pink Target Prograde marker. Once you get close, or if the green prograde drifts too far form the target prograde, burn on the green velocity retrograde marker to bring yourself to a stop, and repeat. Once you're better at this, you can push / pull the velocity marker to approach much faster. If the two crafts are not currently close to each other, you need to get yourself into a different orbit. Pick a point where the two orbits are the closest/touching, and then burn prograde (if ahead) or retrograde (if behind). It doesn't have to be too much. Eventually, you or the other craft will catch up. This old guide is pretty good:
  9. It's been a while since I've been to Moho, but I agree with a lot of the advice. The first time I went, I spent tons of delta-V at the capture burn, and I learned that just getting an encounter is not enough. You need to make sure that the encounter lets you capture efficiently too. One thing that can save you a lot of delta-V is to deal with the inclination while burning at Kerbin. Remember that inclination changes are easiest when you are far out, and burns are most efficient when you're near a large body like Kerbin. Basically burn such that you eject from Kerbin going both retrograde and normal relative to Kerbin, putting you in Moho's plane. You'll want to do this when Kerbin is at the Ascending node (I think -- it might be at the other node). Note that the AN/DN are NOT symmetrical, because Moho has an Argument of the Periapsis of 15 degrees (the angle from the AN to the PE), so one of the nodes is much closer to the PE than the other. You want to burn at the farther node, so you arrive at Moho near its PE. This saves a lot of delta-V in the capture burn because you'll be moving much faster than Moho when you arrive, so you want it to be moving fast too (there's a 6km difference in Moho's orbital velocity, so this can make a big difference). You can save even more delta-V if at Kerbin, you launch directly into the right inclination so that you only have to burn prograde to eject from Kerbin in the right direction. This can be somewhat difficult to pull off. As others have said, you're basically in a phasing orbit after you leave Kerbin, so you should be able to get an encounter if you burn at your PE the right amount. It's somewhat less efficient than just waiting (until you eventually get an encounter), but the difference isn't that huge, because Moho isn't a very big planet, so efficiency gains from burning in its gravity well aren't as big compared to Kerbin. Another option is to use Eve to correct both your inclination and also reduce your PE down to Moho. It might require several assists to do this, and you'd spend a lot of time waiting around, so I haven't really every tried it this way.
  10. You are correct that from a practical standpoint, a 180 degree turn will usually only happen if you're moving very slowly with respect to the body you're getting the assist from. However, for any given velocity, the closer to 180 degrees, the better the potential benefit. At 180 degrees, you pick up 2x the difference in velocity with respect to the parent. For example, if you were stationary with respect to Jool, Tylo would approach you at 2000 m/s (its orbital velocity). If you managed a 180 degree deflection from Tylo, you'd exit Tylo moving 2000 in the opposite direction, and end up moving 4000 m/s with respect to Jool. The problem is that you can't get 180 degree deflection from Tylo while moving that fast. You get a greater deflection if you pass close to Tylo, but at some point, you'll crash into it. However, if you replaced Tylo with a black hole with the same mass, you would be able to approach much closer, and it would likely be possible to get a 180 degree deflection, even when moving very quickly. In general, the best places to do gravity assists are around objects that are both massive and moving fairly quickly. That's why moons like Tylo are a good choice, and why both Eve and Jool are used as well. This article also does a really good job explaining how gravity assists work with pictures.
  11. Awesome looking mod! One thing I did notice from your videos is that Rhode is easier to orbit compared to Kerbin. Do you think you'll ever add an option to make Rhode identical to Kerbin (in terms of atmosphere, mass, size)?
  12. With careful configuration editing, it may be possible to flip the docking port in your save game. Make a backup first. Otherwise, you can try to grab the craft with a gabber arm. I often encounter bugs with the arm though.
  13. I'd generally advise a Space Plane for Laythe because it's too hard to find somewhere to land otherwise. However, a normal lander would work too, if you design it for a water landing. You'd want some way to ensure it stays upright after it lands in the water, and I'd definitely test it in Kerbin's water before sending it off. Treat Laythe as basically about 85% that of Kerbin -- any rocket that has about 85% of the delta-V and 85% of the TWR should be able to make it.
  14. It's been a while since I've done a landing on Tylo, but according to the wiki, it takes around 2300 m/s to land, and about the same to take off. If you're taking up much more than that, you should look at your landing method. I'd definitely do a multi-stage lander, as having sufficient TWR and delta-V will be difficult without staging. It makes sense to have a single ascent stage, and at least one descent stage. Keep engine weight as low as possible. There is no need for super-high TWR values (more than 2). When landing, remember that TWR only matters toward the end. If you can use a mod that tells you when to perform a suicide burn, that can save you a lot of wasted fuel.
  15. It's an early-game engine that gives you good TWR and decent ISP to get you into orbit. You don't really need gimbaling if you do a good gravity turn using the built-in torque of command pods. You can also use it as boosters for a central Swivel, since you don't need all engines to be gimbaled. You do quickly stop using it as you get better engines though.