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Terwin

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Everything posted by Terwin

  1. Want a better one? Don't write yourself into a corner to begin with. The more technical details you give to your audience, the more you tie your own hands behind your back with regards to creating and resolving drama. Examples: A) My ship has a Delta-V of X and a fuel fraction of Y, and I need to get this vaccine to the planet just hit by a plague within W hours or everyone there will die. he plague planet is Z distance away, I hope we can make it! B) A plague hit Planet X! We are the only ship with a hope of getting there in time, and only if we <Technobable> the <Technobable>, and then push the <Technobable> beyond safe levels! With A, anyone who knows enough to understand all the numbers you throw out about the ship will know right away if the ship can get there in time, and anything else will be obvious deus-ex-mahina. With B you can have <Technobable> break-down from pushing it too hard and lots of dramatic struggles and risks to make it on-time with no known outcome until the end. Not to mention, providing technical details does nothing productive with regards to building or maintaining dramatic tension. For the sake of your readers, do not make your story into a technical manual. Making a thrust shorter does not in any way make it more fuel efficient. Usually the inverse actually, as lower-thrust engines are usually more efficient, especially things like ion engines that run for days but could not lift a piece of paper off of a table on earth. Generally speaking, energy density is the antithesis of safety.
  2. I believe that the max change in velocity that you can get from a fly-by/gravity assist is 2x the relative speed of the body in question. At best you are making a U-turn around the body where your relative velocity compared to the moon is the same when you leave as when you arrived, but with a reversed direction compared to the body in question. So, if you are approaching a body from behind with only 100m/s in relative velocity, then after the assist you will be going 100m/s slower than the body as opposed to 100m/s faster than the body when you started, for a total change of 200m/s. The size/mass of the body only affects how low you need to get to achieve this perfect U-turn for a given relative velocity. If it is a small/light body, you may not be able to get close enough without litho-breaking, and bodies with atmospheres increase your minimum altitude without aero-breaking. So choosing the correct moon is usually much more important than choosing the heaviest object available.
  3. WOLF uses exactly the same resources and materials that the MKS system uses, it just uses WOLF-specific parts to extract and process them. The units represent materials over time instead of distinct chunks of something physical to avoid additional processing load, but that is the biggest difference between the two. (use hoppers to convert WOLF materials into MKS materials) KIS has been generally supplanted by the stock inventory system. I do not think that the actually conflict, but remembering what is in which sort of inventory and handling it appropriately could be a headache. I believe USI now has it's own in-situ vessel construction mechanic, making GC redundant, but once again, I do not believe that they actually conflict, it is just that trying to actually use both at the same time may cause more headaches than it is worth, at least long-term.
  4. In the current version of MKS you can specify how much machinery is consumed, including setting machinery consumption to zero. To the best of my understanding zero machinery consumption is the primary difference between MKS and MKS lite, so this setting makes MKS lite redundant.
  5. How are you going to get your hands on the wealth of the Saudi royal family, or other authoritarian régimes? They tax others, they themselves do not get taxed, and anyone who wants to try , will need to get past their tanks and soldiers. Also, how do you take part of the value of a billion dollar chip foundry? a Skyscraper? It is not like these amounts of money are actually sitting around in bank accounts. Any funds in bank accounts would just get shuffled into banks in non-compliant countries anyway.
  6. Imperial evolved over time as a system that could maintain a reasonable level of accuracy with little or nothing in the way of tools. You have a gallon and you need a quart? Divide it in half twice. Need a pint, divide that in half. Units are centered around day-to-day needs, and conversions generally involve halves and thirds, which can be estimated by eye with a reasonable level of accuracy. Metric was engineered from the out-set to be useful for engineering and scientific purposes, simplifying the usage of both scales and conversions that a pre-industrial farmer would never need or use. If you want something that is easy to use in your day to day life where you can eye-ball the difference and make conversions without any tools, Imperial works best. If you want precision engineering, or you want to do complex calculations, or you want to use macro/micro scales, then metric is better fit for purpose. In our highly mechanized world, Metric tends to make more sense, but that will not stop curmudgeon like myself from holding tight to our yard-sticks, gallons of milk, and wanting a pleasant day to be around 70 degrees.
  7. According to here there is roughly 3.14g per day per MW of U235 consumed by a thermal fission reactor. According to this the US produced 843 bln kWh from nuclear power in 2019 1 MW-day would be 24MWh 843 bln kWh/24MWh = 843 M/24= ~35M multiply that by 3.14 grams for ~111 metric tons of U235 converted to by-products for all US powerplants in 2019 According to Wiki, those by-products are iodine, caesium, strontium, xenon and barium. I do not know the percentages produced, but the most radioactive products have short half-lives and are all but gone in a few months, then the radioactive signature is dominated by less radioactive isotopes for the next couple of years, followed by longer-lived isotopes after that. So with just fuel-rod recycling to recapture un-spent uranium, all nuclear waste produced by power generation in the US in 2019 could be carried in a single Starship. If you let those rods sit in a holding pool for a few months or a couple years, you probably reduce that amount significantly. Note: in 2019 19% of US power was from nuclear, so even scaling up to 50-80% nuclear power, you are probably looking at 1-2 SS/year or less to dispose of the waste. Note 2: Electricity consumption in the US went down in 2020, then up in 2021, but still less than 2019. Numbers for 2022 are not yet available.
  8. To start with, the vast majority of 'nuclear waste' are just things that had neutron activation due to being in proximity to a nuclear reaction. For the most part these are no more radioactive than natural materials like granite. Thanks to the linear approximation method that is still in use even after being proven wrong, all of these bits, pieces, and structural materials must be locked away for 10,000 years in a geologically stable environment. For real radioactive waste, like 'spent' fuel rods, just discarding them like we are is terribly wasteful, as something like 80%+ of the fuel is still there, it is just 'poisoned' by reaction byproducts. These could easily be recycled into new fuel rods, leaving only a small amount of actual reaction waste products. These, often highly radioactive, waste products could then be put in to a fast 'breeder reactor'(the navy had one for processing spent nuclear fuel, producing both useable fuel and energy, but it was decommissioned, and no one else was allowed to have one due to the risk of proliferation, as they can also produce weapons-grade materials). Once you start ignoring things that are less radioactive than common, naturally occurring materials, and re-processing 'spent' fuel, you are mostly left with highly energetic materials, that have short half-lives. Generally these are things that could be put in a storge pool for at most a decade or two, then discarded normally as being in the 'low radioactivity' category mentioned above. The only thing that makes nuclear waste management 'impossible' is FUD driven politics.
  9. When I was using near future engines, I remember the large ISRU processor being able to produce lithium from ore. This might not be balanced however as the large ISRU does a straight loss-less conversion based on mass, and ore containers are much more mass efficient than lithium tanks. (But if you are already using firespitter to swap tank contents, this is probably less of an issue.)
  10. I have never seen anything that would let someone manufacture solar panels in their garage, nor any way to produce solar panels cheaply, let alone something that does both. The primary criteria I listed were cheap and easy, whereas solar panels are neither. If solar gets a break-even period of less than 2 years I might consider it cheap, but having a break-even period measured in decades is not so cheap.
  11. Every source of energy has it's down-sides, and we should expect that to continue to be the case going forwards. If environmental groups were really concerned with global climate change, and not just fund-raising, they would have been advocating for nuclear power instead of against it. The ignorant fear, the self-interested stoke that fear to their own ends, and we all get more propaganda until it gets to the point that your 'truth' depends on which source of lies you distrust less. Unless you have a magical power source that people can build in their own garage on a shoe-string budget and then power their entire neighborhood for a decade, the supply for the power grid will continue to be used as a game piece by people seeking more money, more power, or both.
  12. It does get a lot harder to have surface water however, unless you have something like a force-field or gravity generator just for the lake. (Liquid water by itself tends not to have a high structural strength)
  13. A non-spinning moon would have a lower Roache limit, as would a more diffuse/lighter planet or a denser/heavier moon Might also be a matter of perspective, like how the moon always looks closer to the naked eye than to a camera. If a body is held together by something other than it's own gravity, it can ignore the Roache limit as well.
  14. Depends on the range of the aerokinesis field. If the field is similar in size to the blades of a helicopter, then you would get helicopter-type down-drafts, but if you can affect a half-kilometer radius, then it would be a gentle breeze(or less), even with a several-ton vessel. Examle: Google says air at sea-level has a mass of 1.225 kg/m³ A sample helicopter from Wiki has a max takeoff weight of 4300 kg and a rotor diameter of 15m, giving a rotor area listed as ~168 sq m, giving a down-draft of roughly 26kg per sq m or a ~21m/s down-draft This would be a Beaufort number of 9 or Strong Gale A 21m aerokinesis diameter would reduce the required thrust per sq m by half to ~10m/s, reducing the Beaufort number to 5, which is 'Fresh Breeze' A 30m Aerokinesis diameter would reduce that by half again to ~5m/s, giving a Beaufort number of 3, or gentle breeze
  15. I you have aerokinesis, then you just grab some air and keep it next to the skin of the vehicle as a buffer, possibly changing it out if it gets too hot. Maximum mass of your vehicle would be related to: Mass of the total amount of air you can move / mass of your vehicle. If you can extend your aerokinesis field over a wide area, ten you can have a much heavier craft than if the range is measured in inches, just due to the mass of the air you an move. If you are worried about heating, drop the wings and go with a more needle type shape(or rocket-type if you prefer). Perhaps with out-riggers if your aerokinesis field has a range measure in meters and this would let you add engines to cover more air(assuming that such additional volume can adequately off-set the mass+drag). Considering that the frontal area of the engine of a commercial airliner is much smaller than the surface area of the airplane in general, an aerokinesis range of even a few meters outside the skin of the vessel could provide a relatively large amount of thrust if you can push the air with the same speed as the airliner engine. However a relatively light vessel with a longer range of aerokinesis effect might want to be more spherical so that it could rapidly turn in any direction(so long as you do not crush any occupants/control systems), combined with a shorter-range aerokinesis system, you could have a nearly instantly reconfigurable aeroshell made of air which is held in place by the smaller system while the larger system grabs and moves huge masses of air to push it around with a maneuverability that is only limited by the ability of the control systems to withstand the acceleration.
  16. Why? Starship is designed to land on earth after launching SSTO from mars(where SSTO is much more reasonable). Launching from earth requires a SH first stage, but Starship is fine making orbit from mars or the moon, and even has dv left for going somewhere. If you want Star Trek type adventures, your engines(and shuttle craft/transporters) will need to be fantasy, not hard sci-fi. Nothing realistic can manage Star Trek, even in a size-constrained multi-system like the 'verse from Firefly.
  17. The 'difficulty' is more expense and mass fraction than anything else. If you want a realistic vehicle using all of these wiz-bang ideas without ignoring realism, you should expect your 8kiloton STO to have a useable payload of perhaps 50 tons, and costs that might bankrupt a level 3 civilization with each launch.
  18. This does not in any way reduce the force that the ramp would need to apply to the space ship, nor the forces that the ramp would need to undergo during a launch. If anything, this makes the problem harder as you no longer have anything keeping your vessel from sliding off to the side of the ramp and greatly limits the strength of the materials you can use for the surface of the ramp. You would also need a magnetic field strong enough to hold up that 8 kiloton vehicle, and I have serious doubts that a fixed magnet can manage that much force in the area available.(and if it can, it may be a bigger hazard than the engines. Such a strong magnet right next to the engines would also likely cause problems with your magnetic nozzle. This also does not in any way address the issue of losses due to high speeds low in the atmosphere nor the need to make a 90 degree turn so to change the rocket from horizonal to vertical(Rear engines with no wings = falling with a high horizontal velocity unless you are vertical)
  19. The whole point of fusion over fission is that fusion scales down. Fission requires critical mass, providing a minimum possible blast, while fusion scales down to levels that are insufficient to even melt an entire snow flake. Also, you are using fantasy engines, so they have whatever properties you want them to have.
  20. If you are using fantasy drives, why not just assume that you can use them for VTOL as well? Star trek and star wars do not even bother to put engines other than the ones at the rear, yet they still more or less VTOL.
  21. Sounds like the 'deep space' biome. Not many would care about what demarks the difference, but Deep Space is a biome I would expect in KSP2 between the star systems.
  22. A nuclear reaction has three possible states: Sub-critical: The reaction will peter-out and die without external support/neutrons Critical: the reaction is exactly maintaining itself with excess neutrons being removed form the reaction to maintain this state Super-Critical: the reaction is accelerating, usually in an exponential fashion A nuclear reactor wants to maintain a critical state long-term, and switches to sub-critical to 'shut down'. A nuclear bomb wants to initiate a super-critical state until the energy release blows the weapon into pieces too small for the reaction to continue. The faster the reaction, the more energy it can release before it gets blown to pieces. If you want to use the heat from an on-going critical reaction, that would be a Nuclear thermal deign or perhaps some sort of ion engine powered by a nuclear reactor. If you want to slow down a nuclear bomb, that is called a misfire or a 'dud' and may not release even as much energy as a similar mass of TNT.
  23. You are conflating two things: 1) SSTO is inefficient for anything* 2) Chemical rockets are the only thing that is currently useful for achieving orbit *) But science fiction ignores this for the sake of the story and you keep ignoring that Bigger is Better when it comes to chemical rockets, and huge** is the only way to get chemical rockets to SSTO. **) While SH+SS is huge for a TSTO, it *might* be big enough for a reusable SSTO that can actually do something useful, even if it would be terribly inefficient compared to the existing TSTO.
  24. Wiki indicates that 70-90% is good for a turbopump: https://en.wikipedia.org/wiki/Turbopump#:~:text=Turbopumps have a reputation for,this is a severe problem. It looks like the efficiency problems are more with the fluid-handling side as opposed to the gas-turbine side(or at least all the listed issues seem to be related to fluid handling). Also, the 99% includes not just two gas turbines, but also the two pumps, the combustion chamber and the rest of the engine. Even if both turbines are at 99.9% that still means that the rest of the bits combined lose less than 0.9% total efficiency.
  25. CKAN can be kind of Jankey, it is recommended to manually install. As RoverDude no longer supports CKAN, it is possible that whoever made the latest changes left out something important(like USItools or firespitter) and so CKAN is seeing a missing dependency.
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