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  2. Given the extreme environment of Eve, I’ve always wondered what effect this has on engine performances. The Vector, Dart and Mammoth are often recommended for Eve, but I never really saw any quantitative numbers backing them up. Fortunately, the staging interface in the VAB lets us set the environment to Eve at sea level and it’s only a matter of using math to derive Isp values from the deltaV values. As expected, I found that the Vector, Dart and Mammoth do pretty well while most other engines suck. Interestingly, the Thud also performs pretty okay. The highest Isp values for Eve are: Dart: 267; Vector: 152; Thud: 101; Mammoth-II: 97; Mainsail: 96; Spider: 74. All others are below 50 (except possibly the Rapier; I forgot to test that one). The Isp values translate to the highest thrust values: Mammoth: 1332; Mainsail: 501; Vector: 411; Bottle-Rocket: 230; Clydesdale: 228; Dart: 142; Kickback: 115; Thud: 92. Using Eve’s gravity of 16.68 m/s2 (1.7x Kerbin), the highest TWR values are: Dart: 8.5; Vector: 6.2; Hammer: 5.6; Mammoth-II: 5.3; Mainsail: 5.0; Thud: 3.5; Kickback: 3.3. Optimal launch configuration While the Dart has the highest efficiency and TWR, it lacks absolute thrust and an efficient engine is useless if it can’t get its payload off the ground. Since the delta-V calculation doesn’t account for gravity pulling the rocket down, I find that instead the most useful quantity for a launch is the total change in momentum (or impulse) that an engine can deliver, which is equal to the net upward force integrated over time: J = integral (F - g*(mpayload + mengine+ mfuselage + mfuel - R*t)) dt Here F is the engine thrust, g is the local specific gravity and R is the fuel burn rate in kg/s. We can assume that for most cases mfuselage = 0.125 * mfuel . The total burn time can be calculated from t = mfuel /R. The equation then results in: J = (g/R) * ((F/g - mpayload - mengine)*mfuel - 0.625*mfuel2) By solving for dJ/dmfuel = 0, we can find the amount of fuel for which the maximum impulse is achieved: mfuel = 0.8*(F/g - mpayload - mengine) Interestingly, this means that for every ton of payload, you need to substract 800kg of fuel to keep the impulse maximized. From this, we also get the optimal launch TWR: TWR = 1 + (F - g*(mpayload + mengine)) / (9*F + g*(mpayload + g*mengine)) This means optimal launch TWR is always <1.111, getting lower with increasing payloads and gravity, depending on the engine. By adding the optimal fuel mass to the impulse equation, we find the maximum impulse: Jmax = 0.4*(g/R)*(F/g - mpayload - mengine)2 Since g=16.68 m/s2 for Eve, and F, R and mengine are constant for each engine, the only remaining free variable is mpayload. Engine comparison As you can see, the Mammoth-II can potentially deliver the most impulse by far for any payload. In second place is the Vector for payloads below 12t, but above 12t the Mainsail would be a better second choice. Without any payload, the Dart has almost as much maximum impulse as the Mainsail, but that quickly drops off. However, to get the most out of the Mammoth, you’d need an enormous amount of fuel. Without local production, this would all need to be brought in from Kerbin and you would need to manage to land it on Eve without burning up in the dense atmosphere or smashing too hard into the surface due to the high gravity. So, maybe the best value to look at would instead be the maximum impulse per kg of starting mass. The math becomes a bit more complicated at this point, but the Dart would now become the best choice for payloads below 2.5t. Between 2.5t and 5.3t the best choice would be the Vector and for payloads above that the Mammoth-II brings the most impulse per kg: Now, do keep in mind that these are the values per engine. Given the LG size of the Mammoth-II, you could argue it should actually be compared to 7 SM or 3 MD engines for similar footprints. In that case, the Mammoth becomes completely inferior to 7 Vectors and would only be better than 7 Darts for impractically heavy payloads of over 40t. It would perform about the same as 3 Mainsails or 36 Thuds: 7 Vectors would however require much more fuel for maximum impulse than a single Mammoth. So yet another way is to compare the amounts of engines that need a similar starting mass to achieve their optimal impulses. For very large payloads, that would be the case for either 7 Darts, 3 Vectors or 1 Mammoth-II. For smaller payloads, the 7 Darts would deliver far more momentum, followed by the 3 Vectors: Staging configurations For a final comparison, I considered a payload of about 3t (a command pod, a Terrier, sufficient fuel for a circularization burn and some appendices) and an asparagus staging configuration. Using 7 Dart engines would require 3.6t of fuel for the center engine and 13t of fuel for each of the 3 outer stages (so 6.5t per engine), giving a total of 24,000 kNs of impulse and a starting mass of 58t. Using 3 Vectors would require 14t of fuel for the center engine and 34t of fuel for the outer stage (so 17t per engine), giving a total of 22,500 kNs of impulse and a starting mass of 70t. A single Mammoth-II would require 50t of fuel for a total impulse of 18,300 kNs, with a starting mass of 74t. Again the Dart comes out on top, but I do have to note that I used sea-level values for all stages. Performances of the Vector and the Mammoth would especially improve a lot while gaining altitude, while the Dart would only improve a bit. You could consider using a Vector at the center stage with 6 Darts on the outer stage, but the additional fuel for the Vector would then count as a higher payload for the prior stages. This makes the Darts much less effective and it would only result in a total of 19,300 kNs of impulse, while having a starting mass of 74t. In fact, since the Dart suffers so much from higher payloads, asparagus staging is probably not even the most efficient way to use it. Just using 7 Darts without staging would give us a much larger impulse of 43,200 KNs, for a starting mass of just 55t. Using drop tanks while keeping all the engines would be even better. Of course, this doesn’t account for the effects of drag as a result of the wider rocket and the increased acceleration, so the best results might actually be achieved by an in-between solution. Conclusion Given all these results, I would at least have to conclude that the Mammoth-II and the Mainsail are never good picks, at least not when they have to be brought in from Kerbin. The optimal choice would be to use Darts. For larger payloads the Vector is a viable choice to lower the amount of engines, or when stabilizers aren't enough and you really need thrust vectoring (which the Dart doesn’t have). The only advantage that the Thud brings is that it’s radially attachable, but you would need a lot of them to make them work. This was pretty interesting to work out as preparation towards the Under Pressure mission, but it's all just theoretical. I don't have a lot of actual experience with Eve, so I'm wondering how this all corresponds with your experiences.
  3. In addition to the official documentation linked by @JonnyOThan, you may also find this thread useful:
  4. I will not push you towards making a purchase to play KSS2. But I will tell you that it's worth the money.
  5. Using time drops to dilate your time is cheating.
  6. This could be cool, if it did this for all of them I think it would only be fair that it takes longer for each biome, otherwise you could get all of the biomes in just a couple orbits
  7. Part 8: Garibarge against mountains, 2-2 draw WORK IN PROGRESS Flying Christmas Tree finishes taking space science (almost) and brings Not Albatross to explore Laythe. The route taken around Laythe; the image is centered on Crescent bay I was just going faster. I could have limited speed to 40 m/s, and it would have been very safe (except hitting the occasional surface feature) but it would also have been boring. It is a slight modification of the suicide burn. The very efficient landing, used by those that go for low mass records, is to lower orbit to the level of the highest mountain on the equator, then brake while pointing upwards so that the vertical speed is always 0, and time it all so that when they stop they are right on top of the highest mountain. this way minimizes gravity drag. However, timing it all so perfectly is impossible for a human. my variation is a human-friendly compromise that's only slightly less efficient. Misfortune? It was nice, I regret not going more straight north after Gagarin crater and skipping the main patch of mountains. Difficult terrain keeps things interesting, so long as the rover is capable to handle it. 8.1) For ease of mind 8.2)
  8. I love this post let me give my opinions: I disagree with your first point of "auto-fear" I think that the beauty of the game is getting to learn how to launch rockets and get good at the process. I like that they avoid automating parts of the game because if you automate something people will default to it and not learn the actual game. I can see how you may find that tedious however, luckily for players like you there will be orbital colonies that you can launch from already in orbit! This means once you can set one of these space stations up after the colonies update you wont have to worry about launching from Kerbin again unless you want to. I do agree that the tech tree should be a subject that the developers are always looking over and listening to the community about. I myself haven't really sat down and thought about what I think about the tech tree but I have seen a couple posts here bringing it up. They should make a thread specifically for tech tree improvement suggestions and they should take those suggestions heavily into consideration. Finally I love love love the idea of in game rewards for "failure" because they always say they see the game loop as "design - launch - fail/learn - redesign" and I agree this is a great loop but having in game reward like science (even if it is just 1 per component per failure type) makes the whole process much less frustrating and more rewarding! I think that is a great idea! It does also keep you from just quicksaving and making sure all your launches in the "in game timeline" are perfect. This is one of the best ideas I've heard for new gameplay!
  9. Banned to a more elegant time.
  10. ColdJ

    Shower thoughts

    No, not a time loop, I mean stop him from moving in the normal time stream. If you remember the Dr Strange first movie, then you will remember the manupulation of the apple and the going back to see what the page had been in the book. Freezing something so it doesn't appear to move would be easy for the time stone. Or if you like, everybody else is super fast compared to Thanos at that point. That is more like "Sliders" than time travel. it suggests that instead of time traveling backwards you are instead traveling sideways into realities that are at different points in their histories compared to your reality. Also ruins the explanation that Banner gave to the Sorcerer Supreme about what they were going to do. I read somewhere, some one proposed that he sent Thanos and co back to the year and place they came from with no memory of what had happened. That would work but it left a big mess. I personally don't believe you can go back in any way. For me, Time is just an observation of things changing, not something you can affect in any way. I don't see the first method of time travel as everything is destined and life has no choices. Just that in this case, whatever you chose to do will end up with your situation being the one you were in when you decided to go back, so closing the loop you created. As to the second, There is a a great Sci Fi book called "Rebel in Time" by Harry Harrison, that uses it well.
  11. Okay, okay, you win, I'll call SpaceX and tell them someone wants a proper mass simulator on the next flight. Except they're not accepting my calls for some reason.
  12. I am using 2.14.3.0. The problem is intermittent, it doesn’t always occur, and not always on the same Maneuver Planner burn. Sometimes, with MP engaged, I can manually move the spacecraft to the correct attitude and the main burn will occur. The RCS stutter is such that the spacecraft doesn’t move under the guidance of MP. Weird. Is this a bug? Should I uninstall MechJeb and reinstall?
  13. Ever since the Industrial revolution, humans have been searching for more ways to boil water into steam for industrial processes. Coal boilers. Gas boilers. Concentrated solar. Nuclear reactors. Now someone is proposing heatpumps, which is more viable on industrial scale than you might think. And the government seems to agree, awarding them up to 145 million dollars to develop their drop-in heat-pump boilers to convert low-grade heat into industrial steam. The specs seem right, because at minimum, it uses water as a refrigerant, can work on heat sources as low as 29 deg. C and operate at a Coefficent of Performance of 2.1. It's even capable of leaving the gas boilers in place as a backup.
  14. @Shadow Wolf TJC As far as "PartLoader Warning: Variable <whatever> not found in Part" is concerned, that's usually quite harmless. If, by chance, you have parts that use the Firespitter buoyancy module (namely the Firespitter parts pack, specifically) remove them and start KSP again. As for the exception you've shown me, another mod which affects docking ports and/or maneuvers is what's crashing your game and you'll need to troubleshoot and pick apart your install. I'm not going to mod my game as far as you did to investigate. That's not how the help desk works, sorry. There is a catch-all built-in. I found the need for this on my own while making this mod.
  15. Yeah, so while I do like the direction of having some science that takes time to gather, Im not sure if what we have now is the best answer. maybe if it can somehow keep track of progression, simultaneously for each biome as it orbits. so you might put your probe in a polar orbit, let it run for a few orbits and see something like this: (using Tylo biomes for example) - orbital survey / low orbit: ----- highlands -- 100% complete ----- lowlands -- 57% complete (3:23 of 6:00) ---- craters -- 2% complete (0:05 of 6:00) ---- dimple -- 0% complete (0:00 of 6:00) But I dont know if that would be thought of as "too automatic" / "too easy" and maybe defeat the entire idea of making it take time to gather? I dunno. just some thoughts.
  16. 7/10 I'm seeing you around more now.
  17. Today
  18. How about showing it can get anywhere near the 150 tons payload to LEO claimed? What IFT-3 showed was a launcher with 0 tons to LEO payload capability, even when fully fueled and fully expending its propellant. Then how can it do Artemis Starship HLS refuelings when it gets 0 tons to LEO? Bob Clark
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