Grant Exploit

(This was first posted on the Space Exploration StackExchange and the AskScienceDiscussion subreddit first, but I want more input, so I'm posting here as well. As forewarning, the most integral details of this question are bolded.) For context, I have been writing an alternate history involving the accelerated development of spaceflight technology for over 5 years now (one with quite different assumptions from other examples of the subgenre), and one of its long-standing elements has been a wildly-ambitious space probe that would be sent on a Solar System Circumnavigation through a Grander Tour. What does this mean? Well, here are the mission objectives: The main spacecraft body (which I will obfuscatorily name “the Spacecraft”) must fly by every planet (1930–2006) in the Solar System save Pluto. At least a subprobe (“Subprobe A”) must fly by Pluto. Double points if it manages to do so while flying by all 8 other planets. A sample, no matter how miniscule (probably micrometeorites or ring particles), must be returned to Earth by a subprobe or sub-subprobe (“Subprobe B”) after flying by all 8 2006– planets. The course correction to do so may involve as much as an orbital-scale (~9000 m/s) multi-stage solid rocket together with aerobreaking and/or a brutal gravity assist. Double points if it is on or launched from Subprobe A. Triple points if it is on or launched from Subprobe A after the Pluto flyby. Each flyby in the Outer Solar System should preferably be at least 1 synodic period before that of the real-life Grand Tour users the Voyagers in order to prepare for the arrival of a vaguely equivalent program. The base of the spacecraft’s conception was that it would be launched around the time of or before the first outer planets and interstellar probes in real life (Pioneer 10/11) to make time for it to engage on a more proper Grand Tour trajectory. This was reinforced by the fact that said time range roughly overlaps with the 450th anniversary of an Earth circumnavigation expedition done by the crew of a certain navigator, who happens to be the namesake of a far less impressive real-life space mission. So, the rock-hard minimum and maximum are the 450th anniversary of the start of that navigator’s voyage (September 20th, 1969) and the launch of the latter Pioneer, Pioneer 11 (April 5th, 1973). However, it would ideally be launched before September 6th, 1972, exactly 450 years after what was left of that expedition returned, yet as close to that date as possible (i.e. within 1972) to allow as much advanced technology to be used in it as possible—the spacecraft would include developments like 8-bit microprocessors, helical-scan tape data storage, robotic arms, synthetic aperture RADAR, and possibly non-solid-state radioisotope generators. And yes, the first asking of this question was deliberately timed to match with the 50th anniversary of that date and the 45th anniversary of the launch of Voyager 1. (I’d have preferred it to be earlier, but ehh…) Also, the spacecraft’s original conception had it launched on a Saturn IB–Agena D (what I thought was the highest-capacity high-velocity non-Saturn V notional “drop-in” vehicle that could have been made at the time… ignoring that either a Saturn IB–Centaur or earlier Titan IIIE would have greater capacity and could probably be made with similar R&D), but as its size and capabilities grew, its proposed launch vehicle was progressively upgraded until it became the “Saturn 1E-SB”, which consists of 4 stages (more details on which could be provided if required), the last one, not considered integral to the launch vehicle’s identity, being the main course correction stage of the spacecraft. The first 3 stages would have the capability to put the 4th stage and ~5.5-ton spacecraft complex—~28.5 tons in total and ~6.75 tons dry mass—on a trans-Cytherean or potentially trans-Martian injection (up to 3650 m/s tested in KSP RSS RO using a penultimate version of the launch vehicle, probably ~3800 m/s), beginning its Grander Tour… A Saturn V could do so, too, and to be honest I now find justifying the existence of the Saturn 1E-SB somewhat difficult, so I may bite the bullet of switching away from a “Saturn one” platform. Now, how much ∆v would the course correction stage be capable of supplying? A measly… ~5500 m/s. And that’s with the subprobes still attached. So there is a very beefy, though not unlimited course-correction capacity. Now, orbital mechanics is a complex business, and I don’t know if it would even be possible to fulfill even the barest mission requirements given the ∆v budget within that launch window, let alone how it would be done. However, the existence of trajectory designs like this, a flyby of all 2006– planets launched in the same vague timeframe with a negligible course-correction budget, indicates its likely possibility. Note that the 5500 m/s and 5.5 tons payload is a maximum and minimum, respectively—the more optimized the trajectory can be made, the smaller the fuel mass of the course correction stage needs to be, allowing a greater scientific payload, so the more optimized the mission is, the better. And so, the question. Ideally, I’d like to have the specifics of this drilled down by April 5th, 2023 for some sense of timeliness. For more context, this is the encounter order as planned when the conception of this mission reached its modern form: Main spacecraft: Earth→Venus→Mercury→Venus→Mars→Jupiter→Saturn→Ouranos→Neptune→Interstellar Subprobe A: 〃→〃→〃→〃→〃→〃→Pluto→Interstellar Subprobe B: 〃→〃→〃→〃→〃→〃→〃→Ouranos→Neptune→Earth

Ok then, I then deleted all extraneous GameData, and nope, CKAN still didn't recognize RO as installable, and as previously, still recognizes a couple residual mods as installed. CKAN said that RO and a few other mods (unfortunately, I did not take notes on which) had "updated metadata", and offered an upgrade when I launched the program, to which I selected no, partially as I thought it extremely bizarre that it was offering an upgrade to a mod it didn't show as officially installed or installable. Then I uninstalled all those residual mods using CKAN... Nope. Then I deleted the entire CKAN downloads archive... Still nope. I don't know what you exactly mean by a "fresh install"—I did reinstall it.... at least I thought, though it left most of the files in the KSP folder intact. So what should next? Should I total my CKAN folder and reinstall CKAN?

Hello, I haven't played RO since January, partially as I became disinterested with it, and partly as I sort of assumed that with the accelerated update schedule of "Take Two KSP" the RO team would just give in and the community would wither away. Fast-forward to a week ago and my interest was revived, and I found out that my fear was not true (quite the opposite, in fact). So, I backed up my KSP data, uninstalled, upgraded to 1.6.1, and loaded up CKAN (which I also updated) in preparation to upgrade RSS and RO. They didn't show up on CKAN. So then I briefly thought that though they were upgraded to 1.6.1, they weren't on CKAN yet... which is contradicted by this thread. So, I decided to see what happens when I opened KSP regardless. It told me that RO and a lot of other mods were incompatible with 1.6.1, which makes sense for the versions I had, but why CKAN wasn't allowing me to upgrade mystified me. Upon fully loading the game, I found that it was using the stock system and had few RO parts and visible mods. Also worth noting is that this happened both upon loading it from Steam (which loaded stock in 1.3.1) and CKAN. So, what should I do to solve this? I noticed that my GameData folder was full (typically uncharacteristic of a reinstall), so I thought that maybe purging that would allow me to reinstall the fresh versions of RO. Is that an advisable course of action, or should I do something else?

I am creating 2 spaceflight-related alternate histories which would include missions directly launched to Mercury. However, there has never been a direct mission to Mercury (all of them have used gravity assists), preventing me from using an existing launch and the synodic period to calculate their launch dates (the only method I know how to use). So, does anyone know any optimal launch dates for direct Mercury transfers?

Hello, Yesterday, I found out that about a week and a half prior, Realism Overhaul had (finally! ) been updated for 1.3.1. So, I did this sequence of events (I'm on Windows 10, BTW): Backed up saves and screenshots for safety, Deleted my copy of CKAN and the CKAN folder, as it was malfunctioning. Recalling the tumultuous experience I had with upgrading to 1.2.2, I uninstalled KSP and reinstalled it as 1.3.1. I reinstalled CKAN. CKAN recognized the mods that still existed in the Game Data folder, but (presumably because I deleted my CKAN folder), they were marked by 2 capital letters (which I can't recall) and I could not do anything with them. I permanently deleted all the Game Data, as I always have very little space on my computer. This took with it all of my custom engine configs, yaay... Now I could reinstall the mods. I attempted to do so, but it kept aborting the procedure as the mods were attempting to install a craft that was already in the Ships folder, which also strangely wasn't swept away by the reinstall. I sent the craft to the Recycle Bin. I tried again. This time a different craft showed up. What should I do? Should I delete my Ships folder or just the contents? What about the stock crafts or pre-made crafts that may not be provided in 1.3.1 RO?

Thanks @JadeOfMaar! I'll take a look at that mod. I'll experiment on my 100% idea first—I don't think the tangent curves will matter for that.

I'd like to be able to create solid motor configs that have 100% thrust all the time in order to reduce gravity drag for orbital launch vehicles. However, I don't know how the thrust curves in the engine configs are structured. For instance, the AJ-260 FL: thrustCurve { key = 1 0.554323725 -12 -12 key = 0.99425197 0.692904656 -4 -4 key = 0.851189892 0.859201774 -0.952083496 -0.952083496 key = 0.681175941 0.985310421 -0.531426454 -0.531426454 key = 0.63542801 1 0 0 key = 0.498184216 0.985310421 0.255306394 0.255306394 key = 0.323060905 0.914634146 0.285245267 0.285245267 key = 0.157006708 0.88691796 0.31677097 0.31677097 key = 0.03821409 0.831485588 3 3 key = 0.023086798 0.44345898 39.42093859 39.42093859 key = 0.00322197 0.138580931 7 7 key = 0.0001 0.0005 0 7 } wat. I think the first two columns are referring to the propellant quantity remaining and thrust, respectively, but what are the latter two columns? I really don't want to do this, but... @NathanKell? @Phineas Freak? @JadeOfMaar? @Mecripp? Can you help?

Ion thrusters still require propellant. And I don't know how to move topics to different subforums.

After learning how to make propellers in stock KSP, I wondered if it was possible to make a solar-powered aircraft, like Solar Impulse or the NASA Helios. The problem is, all the propeller engine designs I've seen require the engine to be physically separate from the aircraft, preventing electricity from wing-mounted solar panels from reaching it. Is it possible to make a propeller engine that isn't physically separated from the aircraft, or somehow "beam" electricity into the engine? If not, are there any easy code fixes that can allow either of those things?

Typically, as the thrust produced depends on the propeller used and the airspeed, propeller engine performance IRL is measured in horsepower or kilowatts. As stock propellers require a constant amount of electricity to run, we can find their in-game power consumption in units per second easily—in fact, by just looking at the Resource bars. However, there are 2 potential ways to convert this into real units: A solar panel of a certain area pointed ideally at Kerbol from Kerbin will produce a certain amount of charge per second. An in-game power-per-unit-area figure can be calculated from that. Compare that with Earth's 1361 W/m3 ideal power-per-unit-area figure. This will of course depend on the efficiency of the solar panels used, but assumptions can be made. More reliably, the Realism Overhaul mod suite has a conversion factor from units of electric charge to Watts in case a part specifies its power consumption that way. So, it should be possible to measure the power output of stock propeller engine. It should also be possible, though difficult, to measure the mechanical efficiency of the engine by taking into account the rotary's* moment of inertia, angular acceleration, and cruise angular velocity. Has anyone ever thought of this before? Regardless, if you have made a stock propeller aircraft, please post the power output of the planes and engines you've made, as well as preferably their masses. Posting mechanical efficiency would be really awesome. *Most KSP stock props are technically rotary engines.

I actually found this out a couple of months ago on accident, and thought nothing major of it until recently when I badly had an urge to play stock again for its simpler plane construction mechanics, greater exploitability, etc. The question I have is this: Is it safe? I'm worried playing stock KSP (of course, not on the same savegames) while still having RSS, RO, and RP-0 installed may crash it, or corrupt my savefiles. Will it?

I want to create custom configs for solid rocket motors to simulate fictional and alternate historical rockets, yet I can't locate anything that gives the propellant quantity in either mass or volume. Is it in a different file or what? Here's an example config file for the Castor 1 in case you want to take a look: // ================================================== // Castor 1 solid rocket motor global engine configuration. // Throttle Range: N/A // Burn Time: 28 s // O/F Ratio: 2.12 // Sources: // Thrust Misalignments of Fixed Solid Rocket Motors: http://rsandt.com/media/Thrust%20Misalignments%20of%20Fixed-Nozzle%20Solid%20Rocket%20Motors.pdf // The Satellite Encyclopedia - Castor Series: https://www.tbs-satellite.com/tse/online/lanc_castor.html // Used by: // Squad // ================================================== @PART[*]:HAS[#engineType[Castor-1]]:FOR[RealismOverhaulEngines] { %category = Engine %title = Castor 1 %manufacturer = Thiokol %description = The Castor 1 was first used for a successful suborbital launch of a Scout X-1 rocket on September 2, 1960. Castor 1 stages were also used as strap-on boosters for launch vehicles using Thor first stages, including the Delta-D. Diameter: [0.79 m]. @MODULE[ModuleEngines*] { %EngineType = SolidBooster } !MODULE[ModuleGimbal],*{} !MODULE[ModuleEngineConfigs],*{} MODULE { name = ModuleEngineConfigs type = ModuleEngines configuration = Castor-1 modded = false CONFIG { name = Castor-1 minThrust = 0 maxThrust = 286 heatProduction = 100 PROPELLANT { name = PSPC ratio = 1.0 DrawGauge = True } atmosphereCurve { key = 0 247 key = 1 232 } curveResource = PSPC // guesses (note: max is above nominal * thrust_curve_max) chamberNominalTemp = 1500 maxEngineTemp = 1745 thrustCurve { key = 0 0.2 0.6566457 0.6566457 key = 0.08 0.7826234 11.38028 11.38028 key = 0.12 1.091428 0 0 key = 0.177 1.072238 -0.3012535 -0.3012535 key = 0.832 0.9977316 0.2489114 0.2489114 key = 0.91 1.052388 1.565168 1.565168 key = 0.9730649 1.160696 0 0 key = 1 0.93 -4.794868 -6.284284 } } } !MODULE[ModuleAlternator],*{} !RESOURCE,*{} } @PART[*]:HAS[@MODULE[ModuleEngineConfigs]:HAS[@CONFIG[Castor-1]],!MODULE[TestFlightInterop]]:BEFORE[zTestFlight] { TESTFLIGHT { name = Castor-1 ratedBurnTime = 28 ignitionReliabilityStart = 0.91 ignitionReliabilityEnd = 0.994 cycleReliabilityStart = 0.94 cycleReliabilityEnd = 0.997 reliabilityDataRateMultiplier = 2 isSolid = True } } Also, how do you unscramble the thrustCurve for this? It's not simple like it is for the Star 48B or other motors?

I just sent Anatoly Zak this question in email form. Let's see what he thinks of it...

This is an effective repost of my question If the Soviet manned lunar program succeeded, how would the missions be designated? on Quora. The only answer suggested I ask Roscosmos people. Unfortunately, there seems to be literally no Soviet space program/Roscosmos employees, present or former, on Quora. Hence, I re-ask this question here to show it to a wider audience, including people who may be super duper knowledgeable about the Russian Space Program. Comment in question source:

SUXESSSZ!!@ Thanks, @JadeOfMaar and @Mecripp! Here's the final code: // ================================================== // RS-88 global engine configuration. // Inert Mass: 250 Kg // Throttle Range: N/A // Burn Time: - // O/F Ratio: 1.29 (Ethanol version), 1.65 (Hypergolic version) // Sources: // NTRS - RS-88 Pad Abort Demonstrator Thrust Chamber Assembly: http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20050237017.pdf // Encyclopedia Astronautica - RS-88 engine: http://astronautix.com/r/rs-88.html // Boeing - Design Considerations for a Commercial Crew Transportation System: http://www.boeing.com/assets/pdf/defense-space/space/ccts/docs/Space_2011_Boeing.pdf // Used by: // CST-100 pack // RLA // FIXME: // No sources for some values (inert mass, rated burn time and ignition count). // ================================================== @PART[*]:HAS[#engineType[RS88]]:FOR[RealismOverhaulEngines] { %category = Engine %title = RS-88 Series %manufacturer = Rocketdyne %description = High thrust pressure-fed hypergolic engine. Initially designed and built as a part of the NASA Bantam System Technology program, aiming for a low cost, high power propulsion system. It was later modified by Lockheed Martin for use as a launch abort engine. A derivative of the RS-88 is used by the Boeing CST-100 "Starliner" spacecraft for launch aborts under the name "Launch Abort Engine - LAE". Diameter: [1.9 m]. @MODULE[ModuleEngines*] { %EngineType = LiquidFuel !IGNITOR_RESOURCE,*{} } !MODULE[ModuleGimbal],*{} MODULE { name = ModuleGimbal gimbalTransformName = thrustTransform gimbalRange = 4.25 } !MODULE[ModuleEngineConfigs],*{} MODULE { name = ModuleEngineConfigs type = ModuleEngines configuration = RS-88 modded = False origMass = 0.25 CONFIG { name = RS-88 maxThrust = 220 minThrust = 220 ullage = True pressureFed = True ignitions = 1 IGNITOR_RESOURCE { name = ElectricCharge amount = 0.1 } PROPELLANT { name = Ethanol75 ratio = 0.5285 DrawGauge = True } PROPELLANT { name = LqdOxygen ratio = 0.4715 DrawGauge = False } atmosphereCurve { key = 0 324 key = 1 273 } } CONFIG { name = LAE minThrust = 258 maxThrust = 258 heatProduction = 0.88 //0.220 ullage = True pressureFed = True ignitions = 1 IGNITOR_RESOURCE { name = ElectricCharge amount = 0.1 } PROPELLANT { name = MMH ratio = 0.499 DrawGauge = True } PROPELLANT { name = MON3 ratio = 0.501 DrawGauge = False } atmosphereCurve { key = 0 290 key = 1 220 } } } !MODULE[ModuleAlternator],*{} !RESOURCE,*{} } Unfortunately, my LV design turned out to be aerodynamically unsound. Woo... Hoo...