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  1. Like what I do? Want to directly support development? Consider donating via Patreon or Paypal! Set up recurring donations through Patreon ...Or make a one time donation via PayPal DOWNLOADS Spacedock | Github MANUAL | DEVELOPMENT | BUG REPORTS Made by @CobaltWolf, @Jso, @Zorg and @Invaderchaos Massive support from B9PS and SAF provided by @blowfish (Un)official wiki maintained by @Friznit Dependencies (included in download, check for latest versions if you have issues!): B9 Part Switch - Used for fuel switching and for some mesh / texture switching. Community Resource Pack - Primarily used for hydrogen resource. DMagic Science Animate - Used for advanced experiment functionality. NOT THE SAME AS DMAGIC ORBITAL SCIENCE!!! Module Manager - Used for internal patching and adjustments. Simple Adjustable Fairings - used for the new "hard" fairings included from BDB v1.7.0 onwards Deployable Engines - Self explanatory? System Heat - Our new solution for boiloff management Changelog: FAQ What is this mod? BDB adds parts. Lots of parts. Nearly 1000 parts, including launchers, spacecraft, and probes, all in a stockalike style. The focus lies primarily on the US space program up through the Apollo program, though some modern parts exist. They are not perfect replicas, but rather take inspiration directly from existing designs. Care has been taken to research and include pieces for projects that were proposed but never happened, to increase the possibilities available to the player. Parts are made in a lego frame of mind, and screenshots of your unique franken creations are always appreciated! The mod is not recommended for new players, as the mod adds a good deal of clutter to the VAB lists. The mod also adds new standard sizes (such a 0.9375m, 1.5m and 1.875m diameter) of parts in order to more accurately scale to KSP. Now, 1000 parts sounds like it would kill your PC. While the mod certainly is large, the memory overhead is likely lower than you would expect. Care has been taken to ensure the mod is efficient, with methods such as enforcing a strict texel density (a technique I have only used since mid-2017, so the older assets might not be as efficient) and texture atlasing to cram several parts onto each texture sheet. For those familiar with KSP mods, BDB can be considered a stockalike equivalent of FASA, and a US counterpart to Tantares' soviet rockets. The parts are really overpowered! I managed to take a Mercury Hermes to Mercury Moho. The parts in BDB are balanced and scaled against the stock parts. Unfortunately, due to KSP's tiny solar system, that means that the rockets you build will be more powerful than their real world counterparts. For realistic balance, use something like a 2.5x to 3.2x rescale. Scaling can be accomplished via Sigma Dimensions, and scale preset configs are available through Rescale! You could also try the incredibly awesome JNSQ, which comes natively sized at 2.7x scale and works perfectly with BDB! Well, what do I get? Currently, the mod includes nearly 400 parts! A (non-exhaustive!) list is below: I would like to see X, Y, and Z in game! Awesome! I love having people interested in the mod's development. First, check the roadmap to make sure I haven't already planned on making it. If it's on there, it will get done - eventually. Some day. Hopefully. If not, feel free to ask on the thread. Preferably with pictures, or something. Fair warning - I don't have much of an interest in modern rockets, so don't expect to see things like a Falcon 9 or some such in this mod. I also don't plan on covering anything Soviet - Tantares already does a fine job of representing those in a stockalike style. Right now I'm also sort of swamped, with content planned for upwards of the next year! However, if you have something relevant to what I'm currently working on (ie you can't have X rocket without Y part for it) please speak up - I like to be complete! I don't want to download all this, can you split up the mod? I wish it was that easy! At this point, splitting up the mod would be a good deal of work, as well as additional overhead to maintain. Additionally, despite the frequency this gets asked, nobody seems to agree on how the mod should be split up! However, the mod is easily prunable. Deleting folders inside Gamedata/Bluedog_DB/Parts/ will delete that part family without breaking other parts of the mod. For finer pruning, mods like Janitor's Closet can be used to remove parts from within the game. There's something wrong with the CKAN configs for BDB! Myself and the other authors do not maintain the CKAN configs for this mod. @linuxgurugamer has graciously volunteered (I think) to look into any issues pertaining to this mod on CKAN. The Apollo Launch Escape System wobbles. Right click on the LES and autostrut it to the heaviest part. If you don't have a button for autostruts, go into settings and turn on "advanced tweakables". The BDB science experiments don't work. Make sure you have DMagicScienceAnimate installed. All the dependencies are included in the download, so make sure you put everything in the GameData folder you downloaded into your KSP's GameData. The Saturn and Centaur engines don't work. Make sure you have CommunityResourcePack installed. All the dependencies are included in the download, so make sure you put everything in the GameData folder you downloaded into your KSP's GameData. I don't have the LDC/Atlas V/other cool parts people are showing off in the thread. Those parts are still in development. If you want them, download the latest dev version. Warning! These are unstable, unfinished, unbalanced, and will probably break your saves! What parts go to which rocket? They all have weird names, and I'm so confused. The parts all have kerbalized names, like the planets in KSP. There's a list of the real names, and how to build real rockets, in the Wiki/Manual. In addition, there's an optional real names config in the `BD_Extras (No Warranty)` folder, though it might not cover all the latest parts. Type tags into part list search box to narrow down the list to related parts. Useful tags * Mercury, Hermes, Redstone, Etoh * Gemini, Leo (Gemini gets you junk, use Leo) * Apollo, Kane * Skylab * Atlas, Bossart, Muo * Titan, Prometheus * Saturn, Sarnus * S1, S1C, S1E, S2, S4, S4B, S4C (Saturn V is very easy to build using stage tags S4B, S2, S1C) * many more Mercury-Redstone/Hermes-Etoh can't reach space! Your TWR is too low. Empty the upper checkered tank - which, in real life, was actually structural with some avionics. Or add more boosters. Your choice. Mercury Redstone Flight Plan: 1. Liftoff (maintain 100% throttle throughout flight). 2. Pitch over eastward about 0.75 degrees per second. 3. Stop pitchover at 45 degrees pitch (10,000 - 15,000 meters height). 4. Hold attitude to burnout. 5. Jettison tower. 6. Separate spacecraft from Redstone. 7. Turn retrograde. 8. Do stuff. 9. Apogee (hopefully 100+ km). 10. Fire retro motor (optional), jettison retro motor, fall back down (not optional). 11. Deploy parachute at 3000 meters. 12. Ticker tape parade (assuming step 11 went well). Compatibility: Credits: Licensing: #RealThrustHasCurves
  2. KSP 1.12.3 Restock [1.4.3] Last Updated Feb 252, 2022 Release Album It's no secret that some of KSP's artwork is not great. Placeholder art made by a number of amateur artists throughout the game's development has resulted in a scattered mess of styles and qualities which is most evident in the part artwork. Recently Squad seems to be attempting to do something to attempt to address it, but they're taking the art in a direction we stylistically disagree with and does not solve the inconsistency issues that plague the game. Because of this number of community members have come together to try to create a project that revamps KSP's art. This project has the following goals: Create a unity of design and style for all parts: In order to minimize work we'll be targeting the revised aircraft parts, which are the largest consistent block of parts. Preserve the general aesthetic of KSP: We will do our best to keep the stylings of the more iconic parts while updating quality and fidelity. Create consistency in detail level: no more 4k textures for tiny parts! Minimize performance impact: use atlasing and efficient texturing to limit the need for any kind of better hardware than base KSP. Do not affect gameplay or part balance Features About 250 revamped parts (so far!) focusing on the ones that are used most in construction New part variants where they made sense Boattail, compact and regular variants for engines Orange insulated 3.75m tanks! Gold foil-wrapped probe cores New engine effects for all engines Check out the part replacement list for it is LARGE. Asset Blacklisting Restock uses a novel method to stop KSP from loading stock assets - a blacklist file. This reduces the memory footprint of installing this mod by unloading models and textures that are not required. However, this method may break mods that depend on the stock assets. There is an easy way around this as we provide a method to whitelist files. Check the entry on the Restock Wiki for more information about this. Known Issues Please check the issues list for more information on known issues. Some mods are currently not compatible, here's the ones we know about and some fixes. RemoteTech: Some parts will need to be whitelisted, no ETA Frequently Asked Questions Q: Will this break my existing stock craft if I add/remove it? A: It will not. Q: Did you change aerodynamics/colliders/drag cubes? A: We minimized the impact as much as possible. Let us know if you have a concern. Q: I don't like what you did with XXXX. How do I get rid of it? A: We wrote a whole page about it. Q: Something broke! My mod that uses the stock assets isn't loading! A: Look at the Asset Blacklisting section above Q: Will you redo the IVAs? A: Nope. Q: Will you redo more parts? A: Yes. Q: I found a bug, what do I do? A: Stay calm. Ask here if anyone else sees it. If not, post on our Issues board with screenshots/logs/reproduction steps. Q: I see you added some more variants? Can you add more? Every part in purple? A: Nope. Dependencies (Required and Bundled) Module Manager Licensing All configs are distributed under the MIT License All art assets (textures, models, animations) are distributed under an All Rights Reserved License. All plugin code is distributed under the LGPL All bundled mods are distributed under their own licenses. DOWNLOAD MIRRORS Primary (SpaceDock) Tertiary (Github) Issue Tracking and Source KSP 1.12.3 Restock+ [1.4.3] Last Updated Feb 25, 2022 We believe that there are a number of places where KSP is missing key parts - for example, the 3.75m, 1.875m and 0.625m size classes are a little sparse. Restock+ aims to create parts that fill these niche, and is a carefully curated, fully optional project (that requires Restock to be installed of course). Release Album Here's the list of new parts. Some of these parts overlap in purpose if the Making History expansion is installed and will not show up if this is the case. Frequently Asked Questions Q: How did you choose what parts to add? A: Typically these parts are missing from size classes. 3.75m and 1.875m parts for example lack basic conveniences such as orbital engines, drone cores and batteries. Q: Will you add xxxx? A: Probably not. Q: What's going on with the Making History-like parts A: If you own Making History, the Restock+ parts that overlap with the MH parts (fuel tanks, etc), will not be added. Instead, those parts will have their art replaced. Q: I found a bug, what do I do? A: Stay calm. Ask here if anyone else sees it. If not, post on our Issues board with screenshots/logs/reproduction steps. Dependencies (Required) Module Manager Restock Licensing All configs are distributed under the MIT License All art assets (textures, models, animations) are distributed under an All Rights Reserved License. All plugin code is distributed under the LGPL All bundled mods are distributed under their own licenses. DOWNLOAD MIRRORS Primary (SpaceDock) Tertiary (Github) Issue Tracking and Source Awesome People Contributors Artists Plugin Code Lead Testers @Nertea @cineboxandrew @Beale @Well @riocrokite @passinglurker @blowfish @DMagic @Tyko @Poodmund Support Us If appreciate the blood, sweat and tears that has been put into this project, please support us with a donation! It will be used to buy coffee/beer/assuage significant others and we really appreciate it.
  3. Latest Release Source Sample Craft (also found in WildBlueIndustries/FlyingSaucers/Ships/SPH) Gerra Kerman, test pilot. She liked the sound of that! Here she was, standing in front of her first assignment, parked on the tarmac at KSC. Gerra whistled, marveling at the design and then began walking around the strange aircraft. It had a disc-shaped body easily 6 meters in diameter and over a meter thick. Add the trailing wings, and the aircraft spanned 8 meters. Its leading edges had gray carbon panels, ready to resist the heat of atmospheric entry, with dark heat-resistant tiles trailing the edge. A set of windows followed the craft’s contours, but they only gave a view out the front. As she walked around to the back, Gerra saw a sculpted engine housing that sported a strange looking engine with a sloped ramp. Then she realized that the craft was a transatmospheric vehicle, a flying saucer! Read more... Have you ever wanted to pretend that your kerbals found a crashed flying saucer and then the little green men and women reverse-engineered it? With Kerbal Flying Saucers (KFS), now you can! KFS is a mod that lets you research and build your own custom flying saucers that work within established gameplay mechanics while providing exotic twists. It’s as easy as mixing and matching components to create a vehicle suited to your needs. And with its custom tech tree branch and research experiments, you can simulate your reverse-engineering efforts via the stock science system- and possibly unlock parts early! Kerbal Flying Saucers is inspired by real-world saucer-shaped craft like Avro Canada's VZ-9 Avrocar, North American Aviation's Lenticular Reentry Vehicle, USAF's Project 1794, and Northrop's NS-97. Required Mods: Tutorial Videos More Pics: Waterfall engine configs by @Horizons Aerospace
  4. What it does Adds various helpful LED "indicators" to enhance your ships. Broadly speaking, these fall into two categories: Standalone parts: radially attachable LED lights with customizable colors, which can be toggled on/off with action groups. Enhancements to existing parts: add LEDs to stock parts to provide a visible, automatic indication of part status (such as whether a fuel cell is on or off). For details, please see the IndicatorLights wiki, which includes a complete player's guide and modder's guide. Download from SpaceDock License: CC-BY-NC-SA 4.0 Source code How to install Unzip the contents of "GameData" to your GameData folder, same as with most mods. (Note, includes ModuleManager.) Note: You may also want to take a look at IndicatorLights Community Extensions, which includes community-supplied patches to add indicator lights to various popular third-party mods. Things to like Lots of neat features; see gallery below, or the player's guide for full details. Or check out this video review by Kottabos. Lightweight. The "lights" don't actually illuminate anything-- they're just emissive textures that "glow". This means they're computationally cheap and you can have lots of them. Very modder-friendly. Extraordinarily flexible .cfg design allows modders to create remarkably complex behaviors without needing a single line of plug-in code. And it's very thoroughly documented, with plenty of examples, to make it very easy for you to mod your own parts using IndicatorLights. See the modder's guide for full documentation. Third-party mod support is available via IndicatorLights Community Extensions. Configurable colors. All colors in the mod are player-configurable. (Handy if you have color-blindness issues, or simply don't like my default color choices.) Details here. Support for Making History parts. 'Nuff said. I'm not done yet! Still adding new features and content. Gallery (please see the player's guide for full details about these features) New parts At the moment there's just one part, the BL-01 Indicator Light: Batteries All stock batteries have indicators that show the battery's charge level. Fuel cells Activity status indicators. Reaction wheels All reaction wheels now have LED indicators that show their status. Docking ports Fuel crossfeed status, docking-field notification. Crew modules Occupancy indicators, color-coded by profession. They flash if a new crew report is available for gathering. If Community Trait Icons is installed, will use that mod's colors. Otherwise, colors are taken from IndicatorLights config. ISRU units Per-resource converter status lights. Science instruments Solid glow when instrument contains science. Blinks when instrument is empty but useful science measurements are available. Scanners Indicators on the orbital survey and surface scanners. Antennas All antennas have indicators that light up when they're transmitting science data. Robotics For anyone who has the Breaking Ground expansion to KSP, gotcha covered. (Right now it's just the KAL-1000 robotic controller, but there's a good chance I'll be adding more robotics support in the future, so stay tuned!) Video review by @Kottabos (Current as of v0.9. Doesn't include features added after that, such as the science instruments.) More on the way As described above, I'm not done adding to this mod yet. Please see the IndicatorLights wiki for planned features. Feedback welcome! I love to hear what you think, including "gosh, I'd sure like it if it could do <thing it doesn't do now>." A word of thanks Deep gratitude to @NecroBones and @VintageXP, both of whom provided patient, expert instruction to a clueless newbie (i.e. me) who didn't know Blender and Unity from a hole in the ground. This is my first parts pack, and I would have been totally at sea without the help of these fine gentlemen. Their assistance made this mod possible (though they bear no blame for the crudity of my models, that's entirely my own!)
  5. The challenge is simple, but a bit hard to define. Sorry about that but here goes. THE SETUP Start a Science Mode game. No money. No contracts. You'll be busy enough trust me. Make it with (almost) any settings you want, but document them. Use any mods you want, but document them. Challenge yourself! The only setting you MUST have is that you MUST enable saves and reverts. Not many challenges require that one, eh? I would also suggest not making the science gathering all that difficult. I did this with normal science and it wasn't exactly easy. Though you could probably knock down gains to 75% and still complete the whole tech tree in this challenge. THE RULES General rules: You have 9 specific missions, each to land on a specified world or some specified worlds. You must land on the specified world(s) and may not land anywhere else during the mission, except of course Kerbin upon your return. These missions must consist of one single launch from the launch pad with everything you need to complete the mission, and end with the successful return of all Kerbals launched. This counts leftover things from previous missions. No refueling mission 5 with fuel tanks left in orbit from mission 4. Missions are self contained. Only one mission can be ongoing at a time. You may not launch another mission until the current mission has completed successfully. While you can only launch 9 times, you can send things to the runway and launch pad to just gather science around the KSC. If really want, drive wherever you want but you can NOT fly under rocket or jet (or helicopter if you know how to do that) power anywhere. Other than jumps, no leaving the ground. Also, no using other launch sites, either for science grind or legit launches. Everything should launch from KSC. If you really want that desert science, return to there from one of your missions. No generating science in the MPL labs. If you use a mod that helps you in science in any way, specify it. If it generates free science like the lab does, you should consider this rule banning that mod, though you can ask if it's ok if it's marginal. NOTE: You can bring a lab along if you want to reset science experiments without going EVA and level up Kerbals if you turn on that difficulty level. Just no doing science in them. And for the record I don't consider that kind of thing CHEATING per se, it's just way too much science for very little work and it quickly turns this challenge into a "put a lab in orbit of Minmus and win" game. While Breaking Ground (And Making History) is allowed, the science contained therein is not. There is already plenty of science to be gotten in the stock game, so much that I had to limit you to one biome per planet. I can't allow several new experiments to give you even more science. Make robotic landers, though. I want to see lots and lots of those Lander rules: Each landing must be Kerbed, and can not include any probe cores. You may only land ONCE and may not roam from the landing biome to another biome. You can only get science readings from ONE ground biome per world. You may though collect as much flying science during the mission as you can from anywhere you can, so long as you don't break the other rules. Orbiter rules: Once you have unlocked any docking port, you must also leave a craft in orbit of each world landed on, during the landing. This craft must also be Kerbed during the landing, and also may not have probe cores. The lander must re-dock to the orbiter to complete the land-and-return portion of the mission. If you do not need your lander (or orbiter) after that successful docking, the unneeded stuff may be undocked and left behind. Some more general rules: You may use one lander to land on multiple worlds in the longer missions, and the same orbiter to orbit multiple worlds. You can even use one world's lander as another world's orbiter and vice-versa. However you do not have to. Before EVERY launch, make a backup of your save. Alt-F5 named quicksaves are fine. If for any reason you cannot complete all mission parameters with the ship launched while complying with the above rules, you must revert to this save. There are no rescue missions here. You succeed or you retry, from scratch. And possibly with a modified ship or a different mission. NOTE: This does not mean you can't quicksave/quickload! Save early and often, and reload any time you want. If the ship you built isn't up to task, you must revert and fix the ship. But if you just screw up a landing or time warp through an atmosphere, reverting to a quicksave is perfectly alright. When unlocking tech tree nodes after a successful mission or science-gathering jaunt around the KSC, you can unlock nodes within a tier in any order but you must completely unlock a tier before unlocking any nodes in a higher tier. So yes, you do have to unlock nodes with plane parts and probe cores (and docking ports) if you want those parts in higher tiers. The "Only one biome per landing" rule counts upon return to Kerbin as well. For rockets, this means no landing on Kerbin's surface and then taking off to land again. For space planes, it means ... well it means the same thing. Note: If your return vehicle splits up into different pods that's okay, so long as they all land in the same biome. While you can't have a probe on your lander or orbiter, you CAN bring probes with you for other things. Most notably, scanning for ore. You could also bring some as relays. So long as they're not on the orbiter or lander during the landing, it's fine. And no, they can't land themselves or get extra science you don't get with the Kerbals. If you're concerned, ask me. Asteroids are fine to gather science from. If you want to devote some of your precious payload to grabbing one - or just want to put the extra work into rendezvousing with one at Dres - then by all means go for it. I think the extra work being rewarded with extra science is in this case worth it. PROOF Bare minimum proof. I need a picture of, for every mission (in sunlight if possible): Your tech tree before the mission started. i.e., what you had to work with. Your vessel on the launch pad. Your vessel (Lander + Orbiter if you have docking ports) orbiting the target world. Your lander on the surface. Your vessels back in orbit after landing, if you need to re-dock. They can be docked or on the verge of docking. Your return portion of your ship landed on Kerbin. Any special circumstances that need explained. But go for broke. Take pictures like you're on vacation and post them all I'll love them. Or do a video! THE MISSIONS You may do these launches in any order. In particular Dunpollo can be done earlier. I only listed it so far down the list because it's a multi-world mission. Other than that, though, this is a pretty decent suggested order. It's actually the order I did it when I tested the challenge. SINGLE-WORLD-MISSIONS Kerpollo Orbit Kerbin. Should be easy, and about all you can expect to do with the starting tech that you can get from early runway/launchpad science. Munpollo Land on Mun and return. Minpollo Do the same for Minmus. Remember, you can only land in a single biome. I don't care how easy it is to do more. Drespollo Dres DOES exist. Prove it by landing there and returning alive. Eelollo Eeloo's pretty cold this time of year. Which is fine because it will probably take several years to complete your land-and-return mission. Mohollo Mahalo for doing Mohollo, and returning from a successful Moho landing! MULTI-WORLD-MISSIONS Dunpollo Land on both Duna and Ike and return all Kerbals to Kerbin. Evepollo This may be the hardest mission of them all. Land on both Gilly and Eve and return all Kerbals to Kerbin. Joolollo This may ALSO be the hardest mission of them all. Do a Jool 5, but by now you've got docking ports for sure, so you need an orbiter around every world you land on. Remember, you can (but aren't required to) reuse landers and orbiters, so long as they're both present when you do your landing. THE BADGE Here's a quick badge I made for the challenge. It's 107 pixels tall which seems to be the max on signatures? IN CLOSING I fully expect I missed a rule, or messed up a rule. Feel free to comment with any questions or concerns. Don't comment though that it's impossible. I just completed enough of it my own self to prove to myself that it's doabe (I unlocked the entire tech tree) but will be doing it from scratch, and documentation.
  6. The KSP forum moderator's team presents the A Forum User's Guide to the Thread of the Month A brief introduction: As many of you know, since June 2013, the moderation team has been able to bestow the Thread of the Month to deserving threads created by community members. Only recently, within the last few years, have I become involved in creating the thread announcing the monthly Thread of the Month and the annual Thread of the Year. Since my involvement, I will be the first to admit I've gradually made a few changes to both the Thread of the Month and the process used to select them. It is my hope that this guide will answer a few questions about how the moderation team goes about using the nominations we receive from the community for the Thread of the Month, and the expanded categories nominations are filtered into. There are also some other things that I'd like to share with the forum community that goes into the decisions made when the Thread of the Month is prepared. Each major part of the decision making process is explained in this guide. For those of you who strive to create a thread worthy of the Thread of the Month recognition, I hope it helps answer many of the questions I've been asked over the past couple of years. I'll start the guide by explaining the categories and then I'll address the other major points used in turn. The categories explained: One of the changes I wanted to do to the TOTM was to highlight more of what the community was offering each month - and the best way to do that was by creating categories. Currently, here are the categories we use for each Thread of the Month and a brief explanation of what each category is (most of this is copied off the Threads of the Month): Fan-fiction, Mission Reports, and Kerbal Space Program-inspired Creative Works: This category features a thread that, while not directly Kerbal Space Program related, is a creative work, fan-fiction, or other presentation related to the game. If you write fan fiction, do KSP-themed doodles, paint, CGI, or Lego dioramas or craft, or anything else that is creative arts-based and associated with Kerbal Space Program, this is the category where your thread might be featured if it is nominated. Forum Member-Created Challenges and Missions: This category contains missions and challenges created by you, the members of our gaming community. Many excellent missions and challenges threads are created that expand our fun with the game and press our skills, creativity, and sometimes, luck beyond what we get accustomed to. Let’s face it, we all have our go-to design basics and vehicles we like to use. So sometimes, a good challenge can cause us to think of another way to achieve our goals. Ideally, these challenges and missions should be original or older challenges from the forum. Still, they cannot be modifications of official challenges from @SQUAD or @Intercept Games as released on official KSP social media platforms. This category will probably be divided into KSP and KSP2 subcategories. Game Support/Game Mod of the Month: This category features either help with the game (stock or modded) or mods that add quality-of-life gameplay improvements to Kerbal Space Program. This category will probably be divided into KSP and KSP2 subcategories. General community thread of the month: This category features a thread that adds to the community and doesn’t fit the game support/game mod categories. This can be anything. In previous months, we have featured threads involving actual science, suggestions for KSP2, real space missions, and anything else you can think of. Video-based Fan-fiction, Mission Reports, and Kerbal Space Program-inspired Creative Works: This category features a video or other form of cinematography of a Kerbal mission report using in-game video recorded gameplay. In January 2023, I changed this one without warning the moderation team. Most of the more recent cinematic posts have been posted in one thread rather than their creators creating a new thread. And there’s nothing wrong with it; it just meant those creators did not receive the recognition they deserved. A change was made, and for this category only, the TOTM became a Post of the Month (POTM) - with a unique graphic. Honorable Mentions: Just as it says on the TOTM, sometimes it’s a challenge to choose which threads will receive the honor of being selected as the Thread of the Month for our five categories. We get so many good nominations each month to choose from, but we limit it to one for each type. Threads nominated but not selected as a thread of the month become honorable mentions. Honorable mentions will automatically be reconsidered for future TOTMs. After a thread is nominated, it is categorized according to its kind. Any thread that does not fit one of the easy-to-identify ones is put in the General Community Thread of the Month. When we first began the categories, there were times when we would list more than one as a "thread of the month" for that category. Over the past couple of years, we no longer do this. There is now only one thread of the month per category. All other threads nominated for the same type will be listed in the "Honorable Mention" category. What makes a thread a Thread of the Month: In the header of this post, there’s an image containing five points. These five points are important guidelines to determine the difference between an honorable mention and a thread of the month. I want to explain those a bit to give you insight into what we look for in the nominations. The value of the thread to the forum community: Of the five guidelines used, this one is the most important. We consider the value the thread brings to the forum community. Since we have various categories in the TOTM, this becomes easy. The categories allow us to consider nominations of the same kind rather than having to choose just one thread of the month over a variety of threads – even if they were totally different. If a forum game is nominated, it will always be listed as an Honorable Mention. Participation in forum games does not add to a member’s post count. Although forum games are fun and add to our sense of community, they are… fun. Moderator action on a thread does not disqualify it from consideration for TOTM, if nominated. Older threads that have never received recognition as TOTM are eligible to be considered for TOTM if nominated, as they still have value to the forum community. The Original Post (OP) organization/OP design: This is where presentation becomes extremely important. The organization and design of the OP is the second most crucial part of any post we consider for TOTM. A poorly designed OP can distract from the value of the information you're trying to relay to the forum community. Often, this makes a difference in a Thread of the Month and an Honorable Mention (there are other factors, too). If you are trying to design a thread with the hopes of it becoming a TOTM, here are some things about the design and organization to keep in mind. These guidelines are not hard rules or are meant to be strict rules to be enforced or curb your creativity. Basic Original Post (OP) helps: A clean-appearing OP can keep the forum community engaged in your thread. Try to avoid including "clutter" in your OP. These are things that look nice or cute but may not have any real connection to what your thread is about. Use visual organization to help you organize your OP. (Hint - this guide has one, the image at the top of the page. I enjoy making images to help tie things together). Use highlights, such as bold, larger text size, and colored text, to set off headers. Making visual dividers helps to allow the reader to see the divisions in your OP. Be careful with using any font other than the basic fonts (Arial, Courier New, Times New Roman, Lucida Sans Unicode). Those are standard stock fonts. Others, such as Comic Sans MS and Trebuchet Sans MS, may or may not be available to all forum users and may be substituted on some web browsers. Be careful with tables. Apple devices do not like tables and often cut them off if you use preset dimensions. Basic image helps: Use a site that allows you to copy and paste your images with their extensions in place (*.bmp, *.png, *.gif). Otherwise, you'll end up with a URL and no picture. Some sites offer free image hosting, such as Imgur, the most commonly used site on this forum. You are free to set your image dimensions to whatever size you wish. If you use the default size, the device's web browser will auto-size the appropriate images. However, setting hard sizes for your images will create problems for those viewing your thread on mobile devices. Use images that are relevant to your OP. Resist the urge to use images that are off-topic or distract from the information you are trying to relay to the community. Presentation of ideas: This guideline covers how well you explain the purpose of your thread and what it is you hope to do. Some of the best examples on the forum can be found in the mod, challenge, and forum game threads. We are looking at how well you explain the purpose of your thread. Explaining your idea is equally important as your post organization. If your post has a clear purpose and you present your ideas well, your post is probably organized well, too. Here are some suggestions you can use: Use a graphic, image, video, or introduction to explain what the thread is about. Make it easily understandable by the forum audience. Within the introduction, keep it short. You can go into greater detail later on in the OP. Keep the OP structured where the reader can easily follow your progression. The more "cluttered" the presentation, the less likely you will get your idea across. In this thread, I am using a combination of headers, bullet points, and sub-points to relay important information. This is a method I have developed over twenty years of writing academic research and study aids for undergraduate and graduate students. Look around the forum or develop your own style; find what works best for you and use it. Forum community engagement: This one has many different factors and may surprise a lot of you. There have been threads with few responses and many nominations in the past. There have also been threads with many replies and one nomination. But we consider each nomination equally based on community engagement. What kind of engagement did the thread generate from those who participated in it? Did the topic create an opportunity for debate or an exchange of ideas? Did those who nominated it feel it was a good example of what makes a really great forum thread? Nomination: This is probably the least important of all the criteria when we are deciding on which thread becomes a featured TOTM. But because many of you have asked, here's the answer to the questions most commonly asked about thread nomination: Can I nominate a thread again if it was an honorable mention already? Yes, and I encourage you to do so. Since the most recent changes to how we do TOTM, there can only be one per category and we receive a lot of really good nominations. There are some months where we have only a handful of nominations. So, please, yes, renominate honorable mentions you feel are worthy of a second (or more) look - unless they are a forum game. Can I nominate a thread again if it has already received TOTM? No. In the past there have been some mistakes made and threads have earned more than one TOTM. I am working on a side project to track TOTMs so this does not happen again. If you feel a thread is worthy to be considered of additional recognition, you may always nominate it for Thread of the Year (TOTY). I've made this really nice thread. Can I self-nominate it? Sure, you can. However, a self-nomination is given a lower weight than a thread nominated by another forum member. We also ask that forum threads be nominated without "favors" (if you'll nominate mine, I will give you a bunch of likes) as this takes away from the value of the TOTM. Threads of the Month should be meaningful and the nomination should come because someone notices your thread and thinks it has value and NOT because you asked them to nominate it. I've already nominated one thread this month. Can I nominate another one... or three? Yes, you may nominate as many threads as you feel are deserving of the monthly TOTM. Just remember that each thread you nominate should be what you feel represents the best efforts of the forum community. This thread belongs to a user who just joined the forum. Can I nominate them? Yes. There's no better way to encourage a new any forum member than to nominate their thread as a thread of the month contender. Even if they are listed as an honorable mention, it is a great way to bring focus to their efforts! Other related comments about the thread of the month: Future projects for this guide: a guide to the threads of the month listed by year (2016 to the present) Sort-able Google Docs spreadsheet link which will include honorable mentions TO NOMINATE A THREAD FOR CONSIDERATION: If you find a thread you feel should be considered as a thread of the month, then use the “report comment” feature (the three dots on the upper right corner of the comment box) to report the comment. Please put in the text field of the report post “Nomination for thread of the month,” and we will do the rest! You can always nominate more than one thread, too. TO NOMINATE A CINEMATOGRAPHIC POST FOR CONSIDERATION: If you find a cinematographic post you feel should be considered as the cinematographic post of the month, then use the “report comment” feature (the three dots on the upper right corner of the comment box) to report the comment. Please put in the text field of the report post “Nomination for post of the month,” and we will do the rest! IF YOU HAVE QUESTIONS OR COMMENTS ABOUT THIS GUIDE, PLEASE MAKE THEM ON THIS THREAD:
  7. The KSP forum moderator's team presents the Threads of the Month February 2021 edition Greetings, fellow forum members, As you can see, I've decided to do this month's thread of the month. Normally, I run from such things because I am more of a background kind of guy. But for some reason, I felt like volunteering to do this. Maybe it is caused by the never-ending and no end in sight lock downs, the ever growing stack of junk to grade already this semester. Maybe it's a combination of the two. Who knows, but as I told the moderation team a while back ago, hell would have to freeze before I'd volunteer to do the thread of the month. I guess hell froze! One of the neat things of being a part of the moderation team is the ability to give back to the Kerbal Space Program community - and one of the ways we do that is to listen to your voices in selecting the threads of the month. This month, we'll look at two categories of mods. These were the top mods selected by those who participated in nominating threads for February: General Community Thread of the Month: This category features a thread that adds to the community and doesn't fit in the game support/game mod categories. This mod was nominated by members because... who hasn't, at some time, had the problem of not knowing what to name your latest creation? This thread by @Timey has a list of possible names you can use. Have an idea of ship names you'd want to add to this thread? Please do! Game Support/Game Mod of the Month: This category features a mod which adds to the quality of life gameplay of Kerbal Space Program. For February, we have two mods that tied for the top honor in this category: This mod was nominated by several of you and is something that a lot of others have asked for from even the earliest version of the Kerbal Space Program. This mod adds WEATHER to Kerbin! I am sure this mod by @cmet24 will be something many will enjoy! This mod was also nominated by the same number of forum members. It's a planet pack and it features something from the Star Wars universe - the First Order's Planetkiller base! @RJVB09 has done a great job of merging the two together. Honorable mentions: Each month we get so many good nominations to choose from. Sometimes it's a challenge to choose which threads are going to receive the honor of being the Thread of the Month. But because not every thread nominated each month can be selected, there are always those that become honorable mentions. The honorable mentions for February 2021 are: KSP Resolutions for 2021 Don't Click This [1.8.0-1.11.0] Atmosphere Autopilot 1.5.16 Honorable mentions for February may not have made the Thread of The Month this month, but if you think they might be worthy of another opportunity, please renominate it! Congratulations to all the winners of the Thread of the Month for February! We'd like to thank @The Doodling Astronaut, @AlamoVampire, @VoidCosmos, @Spaceman.Spiff, @woeller, and @Superfluous J for the nominations! If you find a thread you feel should be considered for next month's thread of the month, then use the "report comment" feature (the three dots on the upper right corner of the comment box) to report the comment. Please put in the text field of the report post "Nomination for thread of the month" and we will do the rest! You can always nominate more than one thread, too. In case you missed January's thread of the month, you can click here.
  8. I know there are already quite a few tutorials about this topic but I want to write my own anyway Let's not waste any time and start directly In general, there are two methods to install mods: manually and via CKAN. Both methods got their advantages and disadvantages. Manual installation CKAN installation Advantages: Every mod can be installed manually Full control over the installation process Disadvantages: Updating mods one by one can be quite annoying You have to take care of dependencies as well Advantages: Quick and easy installation process Dependencies are handeld by CKAN automatically Version control and easy update method Disadvantages: Not every mod supports CKAN Less control over the installation process A few more things in general and about this tutorial If you got KSP on Steam, it is recommend to move the game directory out of the Steam directory to prevent auto-updates! It is not possible to deactivate updates on Steam but a new game version may break a mod and/or your (modded) savegame, so you definitly don't want to update the game before you know if all your mods will still work fine or got updated. Keep in mind that many mods which are compatible with KSP 1.4.x, are still compatible with 1.5.x and 1.6.x. If you play on 1.5.x or 1.6.x and the mod you want to install isn't available for your specific game version, you can still try an older mod version with good chances of success For most parts of this tutorial, I'm going to use "SCANsat" as an example, for various reasons How to install a mod manually Before you install a mod, you should know your game version so you can get the corresponding mod version. If you are not sure which game version you got, launch the game and take a look at the lower right corner in the main menu: In this example, the game version is 1.6.1. Where to download mods There are three "main sources" for mods: Spacedock (provides a short preview/description and you can search for mods, many mods available) CurseForge (also a short preview/description and a search function) This forum /github (searching the forum can be difficult but the mod threads contain the most informations about the mod. Most release threads contain a download link to Spacedock, CurseForge and/or GitHub) Download the correct mod version On Spacedock, you can download the latest mod version via the "Download" button and the compatible game version is listed in the information panel. If you need a different mod version, open the "Changelog" and Spacedock will present every previous released mod version to you, together with the game version it was build for: The design on CurseForge is similar: One button to "Download Latest File" and a "File" section which contains a list of previous versions: Many GitHub links already direct you to the "Release" section of a repository but if you find yourself in the "Code" section, you have to browser there on your own The "Release" section looks a bit differently but the latest version will always be the first entry. Old mod versions are available as well but there is not always the corresponding KSP version number listed. Sometimes it can be found in the mod name or the changelog of a release. To download the mod, just click on the link for the .zip archive: In fact, @Gargamel already posted a detailed explanation about this topic, so if you are still in doubt how it works, you may want to read it as well Dependencies Quite a few mods require one or more other mod(s) to run properly or at all, these "other mods" are called dependencies. A distinction is made between hard- and soft dependencies: Hard dependency: Required with no exception. If you don't install a hard dependency, you'll experience crashes, errors and misbehaviour of the mod. Soft dependency: Required for additional features but not necessary to run the mod. Dependencies are usually listed in the very first post (OP) of the mod release thread, in the "Information" tab of SpaceDock or the "Overview" tab on CurseForge. Sometimes, the dependencies are highlighted like this: Sometimes, they are just mentioned somewhere in the text, in this case in the install instructions: Take your time to read the informations provided by the mod author, so you don't miss anything crucial Installation Let's start with the step, all of you are waiting for First of all, you need to find and open your KSP install directory. The install location depends on your system and where you bought the game so if you don't know where to look at, search your system for the "KSP_x64.exe". Keep a window with your KSP directory open. Mods are usually distributed within .zip archives. You can un-zip the archive in a separate folder or unpack the files directly where they are supposed to be, that's up to you. I prefer the latter method Open the folder/zip file of the mod in a separate window and place it somwhere next to the window which shows your game directory. Now, there are two cases which can happen: Case 1: The mod folder comes with a "GameData" folder As pointed out by @MaltYebisu, this method doesn't work on MacOS. Mac users, please scroll down a bit and read about case 2 If the mod folder contains it's own "GameData" folder, you can drag and drop it directly into your game directory, which also contains a "GameData" folder. This will merge both folders together (should work on each operating system): Be sure, to drop the folder into an empty space and not into any other folder! Case 2: You get the plain mod folder If the mod is not distributed with it's own "GameData" folder, you drop the mod folder directly into the "GameData" folder of your game: Again, be sure, to drop the folder into an empty space and not into any other folder! On a sidenote: Some mod authors who wrote/maintain multiple mods, uses an additional sub folder for all of their mods (for example: Kerbal Alarm Clock and Transfer Window Planner). Don't worry about this, just treat them like the mod in the case 1 scenario and merge the folders together (Case 3: ModuleManager) "ModuleManager" (MM) is powerful mod on it's own and a common dependency for many other mods but so far, the install instructions don't fit for MM. It is a little bit special in two ways: First of all, you will not find a release version within the github repository, on SpaceDock or CurseForge. In order to download ModuleManager manually, you have to visit the MM thread here in the forum: The very first post of this thread contains multiple download links for MM to fit for different versions of KSP. You have to scroll down a bit to find them: If you cannot find your KSP version in this list, follow the instructions in the MM thread. Also, MM is distributed as a plain .dll file and to install it, you have to place the "ModuleManager.dll" directly within the "GameData" folder of your game....no sub folder or anything else, just like this: (Picture was added quite some time after I wrote this tutorial, please don't get confused by the different mods which are installed here, compared to previous screenshots) That's already everything you have to do, MM is now installed properly How to install a mod via CKAN CKAN is a powerful and very well supported tool to manage your mods. You can install, update and remove mods with just a few clicks and even dependencies are handled automatically. It is available for Windows, Linux and MacOS and can be downloaded here: Launch CKAN After starting CKAN, you are asked to choose a KSP installation (you can manage multiple installations and versions): CKAN automatically searches in some default installation paths for KSP, but if you followed my recommendation from the beginning and moved it somewhere else, you need to add it manually. Click on "Add new", navigate to your KSP install and select the "buildID64.txt". On the first run for a new KSP install, CKAN will also ask you if you want to update the modlist and repository on each launch. I would suggest to allow both options so you are always up-to-date but it's up to you: Basics about the UI The UI of CKAN is pretty intuitive: By default, all mods which are compatible with your KSP version will be listed. Since the list will be pretty long, there are some search options available like "mod name", "author" and "description". You can also decide which mods are listed in general by setting up the filter: Manage your mods As soon as you found the mod you want to install, click into the little box on the left to select the mod: Now, the "Apply changes" button becomes available. Click on it, to display the changeset (you can also click on the "Changeset" tab). In this example, you will notice that ModuleManager will be installed as well even though we didn't select it manually. ModuleManager is set as an dependency for SCANsat so CKAN will install it automatically: Hit "Apply" in the lower right corner to proceed. The next two steps are optional, it depends on the mod you want to install: Some other mods may be recommend or suggested to use along with the mod(s) you want to install. The main difference between those options is the pre-selection: Recommend mods are "opt-out" and suggested mods are "opt-in". In both cases, you will find a button in the lower left corner to select or de-select all mods from these lists. If any of these lists appears, pick your choices and click on "Continue" to proceed. CKAN will now download and install all selected mods and their dependencies If you want to uninstall a mod, just unselect the mod in your list and repeat the installation steps. Dependencies are not removed automatically but if you remove a dependency, every mod which depends on it will be removed as well! Advanced stuff CKAN provides some very useful tools and informations and I want to show you a few of them. Compatible KSP Versions by default, CKAN will only lists mods which are compatible with your game version. Since many mods which are compatible with 1.4.x still work fine in 1.5.x and 1.6.x, you can allow CKAN to show and install these mods as well: Just select the versions you want to allow and apply the changes. Metadata/Relationships/Contents/Versions On the right side of the CKAN UI, you will find four tabs to display Metadata, Relationships, Contents and Versions: Metadata shows some general informations about the mod like version, author and links to the homepage (usually forum post) and the source code. Relationships shows informations about dependencies, recommendations, suggestions and mod conflicts: Dependencies are marked with a "star", recommendations got a "thumb up", suggestions are marked with a "i" and conflicts are marked with a "!". If a mod name is highlighted red, it is not compatible with your game version (if it's a dependency, you cannot install the mod!). You can double click on these mods to find the corresponding CKAN entry. Contents will show you a simple list of the mod contents but it requires to download the mod. There is also a button there to download it (without installation). Versions provides a list of all available mod versions. Compatible versions are highlighted and if you want to install an older mod version, just double click on the list entry. If a newer version is already install, you need to remove it first. I guess that's all for now, fedback and corrections are welcome Happy modding
  9. Talk like Up-Goer Five: Express complex ideas using only very simple, common words. For anyone who has somehow managed to miss it, a while back xkcd had an absolutely brilliant strip: a schematic of the Saturn V, carefully labeled.... but with all terms restricted to only the thousand most common English words. This is where the KSP community gets the term "you will not go to space today." https://xkcd.com/1133/ This game is to talk like Up-Goer Five. That is, you have to express complex ideas using only the most common English words. Here are the rules: The person before you ends their post with a brief paragraph of something reasonably complex to explain. You need to take their post and re-word it using this tool (it lets you type what you want, and draws a red line under any "forbidden" words): http://splasho.com/upgoer5/ You can paraphrase if need be (you'll probably need to). The one really hard rule is, your "translation" has to fit in that tool's edit box with no red "forbidden words" underlines at all. Post your translation inside a spoiler box, so that people reading your post have a chance to guess an answer first, if they want to. Then provide a technical paragraph of your own for the next person to take a shot at. You're not allowed to answer your own post; someone else has to. But you're welcome to come back again after some other folks have had their turns. Guidelines for the "technical paragraph": Don't make it too long, please. Just a sentence or two is plenty. (Otherwise nobody will want to take the burden of "translating" it.) Don't make it so hard that nobody understands it. It should be something that a typical KSP forum user can understand without having to go look stuff up. Ideally the post should be about KSP-relevant topics, e.g. spaceflight, astronomy, engineering, KSP game advice, etc., but that's not a strict requirement, just a suggested guideline. (Props to @Deddly for pointing out the upgoer5 tool to me, which is what gave me the idea for this game.) Just as an example, here's a sample technical paragraph: SRBs are useful as boosters on the launchpad, because they're inexpensive and provide a lot of thrust. However, they're less efficient as upper stages, due to having a low Isp. Here's my stab at translation, using the above-linked tool to validate it: Fair 'nuff? Okay, to get the ball rolling, here's a technical paragraph for someone to start with: Building a SSTO spaceplane is challenging, because not only do you need to balance air-breathing engines with those that work in a vacuum, but also the ship needs to be aerodynamically stable at high velocity.
  10. Due to various reasons we are currently unable to do any further battles. For that reason, this thread is currently on hold until that situation changes. This thread is a continuation of the Air Superiority Fighter Competiton Unlimited by @Box of Stardust (who's still co-owner of this thread) Blablabla there used to be something about war. Let's be honest though, we don't need a reason to build fighters, we do it for the fun of it! This is probably the most rigorous BDA dogfighting competition out there, with the loosest rule set promoting maximizing combat aircraft potential. We only care about one thing: to build the most superior dogfighter. Every battle (Which can be run by me, but I'm encouraging everyone to run their own battles to speed queues and such up) is closely examined to be able to identify and rate a fighter's performance with intricate breakdowns. If you're willing, you'll become very familiar with how BDA works and how the AI functions, as well as its various quirks, and how to apply such knowledge to dominate most other BDA competitions. So this is like Top Gun, for BDA. In @Box of Stardust's opinion, only 25% of the actual construction makes a good BDA fighter. 30% is the weapons carried and how they are used, and 45% is the AI pilot settings. Are you prepared to master all 3 of them? AIR SUPERIORITY FIGHTER COMPETITION UNLIMITED VIEW THE LEADERBOARD, AIRCRAFT RATINGS, & SUBMISSION QUEUE (Offsite leaderboard to allow easy editing by everyone at all times) we've also got a discord server This is a King of the Hill style challenge, but with changes, making it more of a "Hill or Valley" style. Two tiers of aircraft will be maintained, the 'hill' and the 'valley'. General participant entries will always start fighting against the #6, should they fail to beat this one, they will fight the #10 instead. Fail again and you will simply not make the leaderboard. On the other hand, if you manage to defeat the #6, you will continue testing upwards against the tier 1 board. Beat the #10 and you will continue testing upwards against the tier 2 board. Veteran participants will have their entries start their test run against the Tier 1 #5, following the same rules. The competition has rolling admission with no deadline for submissions. Fights will be conducted on KSP 1.6.x with BDAc 1.2.x. Privately testing your aircraft against other competitors in AI only dogfights is not only allowed but highly encouraged. Aircraft built in earlier version of KSP and BDAc will not compete since they probably won't perform at their best thanks to AI and weaponry updates. (if you've got older aircraft, basically just run them in the current environment and tweak them if necessary, then submit) RULES OF AIRCRAFT CONSTRUCTION 1. Construction All dogfights are run by BDAC AI. This means all actions must be automated, excluding initial start-up staging (however, this can be automated as well by binding engine start to SAS) and any drop tank unlocking (due to the programming of BD Modular Missile Manager); drop tanks must be programmed with Modular Missile Manager There is a maximum 100 part count and that's it. Armor settings (per part) must be at default (0). Armor plating (the BDA part) is not allowed since it gives a massive advantage with no serious disadvantages to hold it back. Once you have submitted an aircraft, you may modify the file in KerbalX until the first battle is run. No further modifications can be made after that time. You are welcome to remove aircraft before testing. Once an aircraft has made roster, it cannot be removed from the roster by administrative action and will continue to test, for fairness to other competitors. Aircraft designers are solely responsible for the modification of their aircraft. Do not ask judges to modify your aircraft for you. (However, exceptions are made for minor issues related to BDA quirks, requiring modifications that change nothing on how the aircraft performs, but just fixes any problems that might be caused by BDA quirks.) You are welcome to submit a design as many times as you like, if you modify it. Please note variants (fighter 2, fighter 2a, fighter mkII, fighter mark 2, fighter "somewordshere", fighter AUSF B, etc.). They will be subjected to the Replacement Rule if applicable (see Rules of the Leaderboard). 2. Mods BDA 1.2 for KSP 1.7.2 is the current competition environment. In the interest in allowing newer designers to be competitive, all aircraft must be modified solely within KSP. Any text editing is strictly prohibited. EditorExtensionsRedux is highly recommended for greater control over aircraft construction. Also to be able to toggle 'All Rigid' and 'All Autostruts' to reduce need for struts and general wobbliness. The mod list for this competition is generally open-ended, however, it is preferred to keep mod count to a minimum. We highly recommend Airplane Plus, though it is not a required mod. TweakScale is also permitted. Ask first if you are using a mod outside of our common list, especially parts that include new weapons, shields or armor. Mods that contain parts that introduce tactical advantages, such as radar invisibility, may be permitted if part of a larger package, but said parts are not. Judges may ask for part removal based around mods that do not serve a combat purpose, or are not usable by BDAc. This includes Infernal Robotics, Attachment systems, and ejection seat modifications. If you wish to be a judge WorldStablizer is required. 3. Weapons At no point can more aircraft be present on the tracker in BD Armory than what was originally placed on the runway; i.e., no parasite aircraft. The following weapons are permitted: -Any fixed BD Armory weapons -Any fixed Aviator Arsenal weapons -The 105mm howitzer and Abrams turret from BD Armory (for kicks) The following weapons are banned: -Turrets in BD Armory not mentioned above (USAF laser, .50 cal turret, Millenium turret, Goalkeeper CIWS, etc) and Aviator Arsenal (b-17 turret) - HEKV missile. -any mods not mentioned here that pertain to weapons (ask first) (Tenuous) There is no weapon limit. RULES OF ENGAGEMENT Fighters will begin in a standard formation arrangement on starting runways at combat locations. (Frontmost left center line, Middile right edge line, Rear left edge line). Battles are currently conducted by having start points at the KSC runway and the island runway. Fighters will sortie out against each other in missions of 3v3 maximum. There is a maximum of 1-plane-count difference; 1v3 sorties are not valid, rendering defeat for the team with only 1 aircraft left availble. Battles (defined as the full series of sorties between two aircraft types) are fought until sufficient depletion of one team's aircraft reserves, with victory awarded to the team with more remaining reserve aircraft. A unit will begin its combat debut with 7 aircraft in reserve. This reserve number will be affected by defeats or margins of victory after every sortie. Reinforcements are granted after every sortie based on amount of enemy aircraft killed, on a 1-to-2 basis; 1 additional reserve aircraft is granted for every 2 killed opposing aircraft. Reinforcements can only be granted to replace lost aircraft, with the maximum reserve amount remaining at 7. Surviving aircraft are not subtracted from the reserve. Surviving aircraft are defined as flyable by the BD AI in a stable manner, and retain some wing surfaces and an engine. Fuel is not necessary. If aircraft battle for 5 sorties with no apparent victor, a sixth, final 5v5 sortie will decide the results. Filming is conducted as follows: Sortie #1 filmed from neutral ground observer (location beacon); this reduces the effect of the game physics by staying in a neutral frame of reference (explanation here) essentially creating an unbiased battle. Sortie #2 filmed from offense team; this is for observing the combat performance of the up-and-coming craft, against an opponent that has already been observed and analyzed. Sortie #3 filmed from defense team; switching sides for fairness, as well as observing combat performance of this craft versus a new opponent. Sortie #4 switches back to offense team, and etc. RULES OF THE LEADERBOARD Veteran competitors are those who have achieved Tier 1 Rank 3 at least twice, or achieved Rank 2 or Rank 1. The Tier 1 Leaderboard is open to anyone. It is called the Veteran Leaderboard due to the high-competitiveness of the aircraft in this leaderboard. The Tier 2 Leaderboard is also open to anyone, but imposes restrictions on Veterans. A Veteran may not place in this board if at least 2 spots are held in Tier 1. A Veteran aircraft that has placed in Tier 1 cannot drop down into Tier 2 if pushed downwards after a defeat; it will be removed from the active leaderboards. Replacement Rule: This rule concerns an aircraft variant of an aircraft already placed on the leaderboard. Should these aircraft battle each other, the winning variant remains on the leaderboard. If the winning variant is the newer aircraft, it will continue testing against If the winning variant is the older aircraft, the newer aircraft will not place and its battle testing ends. Re-Advancement Rule: This rule permits a settled aircraft on the leaderboard to restart its advancement upwards upon defending its position by the number of times it is placed (e.g., #5 defended 5 times). The competitor may choose to challenge the next-placed aircraft. The battles conducted will be based on a 12-plane reserve flying 5v5 sorties, minimum of 3 required to sortie, no reinforcements granted. If the challenging plane is victorious, it will continue its climb up the leaderboard according to standard Rules of Engagement.
  11. Hey! I've always been in love with atmospheric flight, but it was not until I played KSP that I found a fondness for spaceflight. I've always had a love/hate relationship with maths, i.e, I love the practical science/engineering/business applications of it, but it costs me horrors to do anything beyond basic equations. Anyway, a few weeks ago, as I was browsing the Internet, I came across a small PDF booklet that piqued my curiosity. It was titled "HOW to DESIGN, BUILD and TEST SMALL LIQUID-FUEL ROCKET ENGINES." I gave it a quick reading, skipping over most of the maths, and realized that the apparent complexity in the design of a rocket engine stems not from the engine itself, which is a relatively simple machine, but from the fact that a flight engine has to fit a very harsh set of criteria: It needs extreme levels of both thrust and efficiency. It has to be extremely lightweight, and the tanks and piping have to be lightweight too. Cost is usually not an issue, or is pretty low in the priority list. That set of criteria produces the awesome beasts we know and love, but in the process also makes them extremely complex and costly machines. (Think turbopumps, regenerative cooling, exotic materials and building techniques, cutting-edge avionics and software, ultra-precise machining, etc) I realized, that, were one to have a different set of priorities, one could take the design of rocket engines out of the realm of the true rocket engine engineers (usually teams of specialists in aerodynamics, chemistry, thermodynamics, stress analysis, avionics, and the list goes on and on) and into the hands of a single hobbyist with barely high-school math skills like me. Enthusiastic, I gave the book a more thorough reading, and found out that it was more of a "How To" guide (Insert X value into Equation 4, take it from table B, and so on), and less of a true rocket engine design book. Given the fact that I actually want to learn design instead of just blindly following along a guide, I decided upon complementing it with other bibliography, mainly "Rocket Propulsion Elements", a monster of a book at 700 pages, and filled to the brim with complex math, which, nevertheless, has managed to solve (with considerable effort and headache on my part ) all the doubts such as Why is X done in Y way?, where does this precomputed value we're told to use come from?, etc. left in the wake of the smaller book. Hence I started the design process, and am currently in the phase of producing CAD drawings for manufacturing and assembly (i.e, I'm almost done) I've decided to share the process with you in order to: Give back to this awesome community at least a tiny bit of which it has given me over the years of playing KSP. Fully review the design process from start to finish as I write this, in search of errors. Learn even more as I search for ways to explain complex concepts in forms that are simpler to grasp than mere maths. Without further ado, let's dive in! I started the design process by listing a set of criteria for the engine to meet, in order for it to be a realistic, doable project for myself. Things I want or need: Simple. Safe (Well, as safe as a controlled explosion can be anyway) Cheap to build and operate Things I do not want or need: Extreme high performance. Or any performance at all. As long as it makes a supersonic flame and lots of noise, I'm happy. Lightweight. Expensive/Hard to find/Toxic propellants. Regenerative cooling (Arguably the hardest part in the design of any rocket engine) Expensive/exotic materials. Complex/extremely precise machining of parts. Gimbaling Given that different design criteria, the project becomes a lot simpler indeed! After outlining my requirements, I made the three most basic decisions that will drive the rest of the design process. Propellants to be used. How will the propellants be fed to the engine Thrust level to be achieved. After careful consideration, and a dive into Elements of Rocket Propulsion, and some Wikipedia to check chemical properties, I settled upon Gaseous Oxygen and Methyl Alcohol as propellants. The oxidizer, gaseous oxygen (GOX) is cheap, easy to find, non toxic, non cryogenic (does not require cryogenic valves, piping, engine pre-chilling, etc), has a slightly higher performance than liquid oxygen, and it also comes pre-pressurized (No pump required). It has a big drawback, in that the required tanks and pressure regulation devices are large and heavy (think high pressure storage of a gas which uses up a large volume), and, while that would be an instantaneous No-No for an engine to be used in a flight rocket, it was unimportant for my intended use. The fuel, methyl alcohol, also known as methylene or wood spirits, was chosen because, while it is more expensive than gasoline or kerosene, it burns at lower pressures and temperatures than those, therefore making the unspoken requirement "The engine should not melt/explode" a bit easier to comply with, and it can be bought at any hardware store. Methyl alcohol is toxic, but only upon ingestion and it's not horribly toxic or carcinogenic like other propellants or oxidizers such as hydrazine, aniline, red fuming nitric acid, dinitrogen tetroxide, etc) I also decided to use a pressure fed design, as, in keeping with the simplicity premise, I want to avoid turbopumps, gas generators, and all that sort of things that make complexity, cost, and the number of potential failure points to increase. The thrust level I decided upon was 100 newtons (10.2 Kgf or around 22 lbf). It's pretty darn puny for a rocket engine, but it's a nice round number, and should still be an interesting challenge, which should be achievable without: Needing huge chamber pressures/temperatures. Having a large fuel consumption. Rocket engines are inefficient machines by nature, and I don't want to go broke after the first few minutes of operation, With that decided, it is time to determine the basic operating parameters of the engine, such as mass flow, chamber pressure, etc. that will then be used to determine the materials and physical dimensions of the engine. That is already done, but I have to review it and convert from my scribbled design notes to a good quality post. Until then, I leave you with this render of the combustion chamber / nozzle assembly as a teaser of things to come. Dec 04 2015: In the last installment, I decided upon the propellant combination and thrust target. Today, I will determine the most basic operating parameters of the engine, and, upon those, calculate some other parameters which must be known in order to start calculating the basic physical dimensions of the thrust chamber and nozzle. Also, I keep all the parameters that I determine/calculate, in a large table, that is kept handy and lets me have all the data that I might possibly need, ready at a quick glance. This is the table so far, and from now on all results will be added to it, and data for any calculations, sourced from it too. ENGINE MASTER DATA TABLE Parameter or Dimension Value Metric Imperial Propellants GOX/Methanol Thrust 10.2kgf / 100N 22.5 lbf Now, in order to get started with the physical design, we have to know a few parameters: Chamber pressure (Combustion pressure) Combustion Temperature. Mixture Ratio (Proportion of oxidizer to fuel) Approximate ISP (This is mostly a rough number dependent upon the propellant combination, and will be later adjusted to account for engine geometry losses) These parameters can be calculated, but designing an engine from scratch, with no reference numbers, is a daunting task. Fortunately there are huge amounts of precalculated data on the subject, made available by either government or private organizations, and we can easily source them from tables. As indicated on the table, these parameters are determined for expansion to 14.7 PSI, which is sea level atmospheric pressure. That is good enough for me, because this engine will not be used at very high altitude or a vacuum. (I live at 2700 ft above sea level) Also, not indicated on the table (one of the things the book assumes you to know/realize) is the fact that these pressures, temperatures, and ISP's, are based upon a stoichiometric mixture ratio (there is just enough oxidizer to burn all the fuel). Any other ratio will result in lower pressures and temperatures, and less performance, which makes sense, because you are either low on oxidizer, having unburned fuel go through the engine, and then burn with the outside atmospheric oxygen without producing useful thrust, or you have an excess of oxidizer going through the engine, and, given that there is not an unlimited amount of space inside the engine, any excess in oxidizer means a corresponding lack of fuel. (There is an exception to that if running fuel-rich reduces the molecular weight of your exhaust, such as in hydrogen/oxygen engines, but that is honestly beyond the scope of this discussion) Now we are ready to determine a few other rough parameters, most importantly, the engine mass flow rate. The engine mass flow rate will let us know the mass of propellants required for operating the engine at the desired thrust level. The formula for engine mass flow rate is: To understand why that does even make sense (It took me awhile to realize why it did, and I was very confused before that) you have to take two things into account: Mass conservation principle. No matter what is chemically happening inside the engine as propellants are burned, the same amount of mass that enters, will leave. Unless you somehow create a nuclear reaction, in which case some mass will be converted to energy, but that is a very, very, very unlikely outcome Specific Impulse (ISP) is just a fancy way of saying "Hey, this engine could develop X amount of thrust if it burned 1 unit of mass per unit of time" Thus, given that we know our thrust target and also know our rough ISP, we can proceed to calculate the amount of mass entering and exiting the engine per second. I'm pretty sure this engine will consume less than 0.1 kg of propellant per second, but let's find out the exact value. 100 Newtons are 10.1971621 kgf. Therefore our engine has a thrust of 10197 grams. Ah, metric system, how can I not love you 10197 / 248 = 41,116935483870967741935483870968 grams/sec. So, when the engine consumes 41.12 grams of propellant per second, it will emit 41.12 grams of exhaust gasses per second, and produce the 100 newtons of thrust. (In theory). Now based on that total, we will determine which part of the propellant mass is fuel and which part is oxidizer. (This will be used later in the design of the injectors, and fuel system and is better determined now than then) Given the oxidizer/fuel ratio of 1.2, as per table 1, we then can determine the mass flow ratios to be as follows: Oxidizer flow = Emfr * R / (R+1) Oxidizer flow =0.403*1.2/(1.2+ 1) Oxidizer flow = 0,2198181818181818 newtons / sec oxidizer Fuel Flow = Emfr * R /(R+1) = Fuel Flow = 0.403/(1.2+1) Fuel Flow = 0,1831818181818182 newtons/sec fuel I know I'm not supposed to use newtons as a mass unit, and later realized that mistake, but the results are the same whether I use pounds or grams , only expressed in the pertinent unit. I have no clue why this is so, and if anyone could explain, I'd be grateful. Now with these parameters calculated, we can dive into the meat and potatoes of the project, and start calculating the physical dimensions of the engine, and also you'll get to see me suffer through some more complicated maths, but that will have to wait for the next installment. Until then, this is the engine data table, with all the data that we have determined or calculated so far. ENGINE MASTER DATA TABLE Parameter Value Metric Imperial Propellants GOX/Methanol Thrust 10.2 kgf 22.5 lbf Chamber Pressure 2.068 Mpa 300 psi Mix ratio 1.2 ISP 248 s Total Mass Flow 41.1 gr/s 0.0906 lb/s Mass Flow (Oxidizer) 22.42 gr/s 0.049428 lb/s Mass Flow (Fuel) 18.68 gr/s 0.041182 lb/s If you have any insight, questions, or even better, have found an error, please let me know Dec 12 2015: Hey! After determining operating parameters, today we are going to determine some gas values, that we will then use to determine chamber dimensions, nozzle outlet diameter, expansion ratios, throat diameter, etc. Let's get started! The idea behind a DeLaval nozzle (That's how a rocket nozzle is called) is to transform a high pressure, high temperature, low velocity gas, like the combustion products, into a low pressure, relatively low temperature, and crazy-high speed gas. (Remember that momentum = mass times velocity, and given that gasses tend to be very light, in order to produce useful thrust, velocity has to be extremely high) Velocities of 2 km/s are not unheard of for small hobby engines This image shows the profile of the gases in a DeLaval Nozzle: Notice that the gasses after the throat are supersonic, and that is done in order to prevent pressure perturbations from travelling upstream (any pressure perturbations travel at the speed of sound) This is critical, because otherwise the nozzle would behave as a Venturi tube, and produce an exhaust of similar pressure and velocity as given in the inlet, which would be useless for us. Now, you'd think that calculating a diameter that will produce a desired Mach speed would be easy, but it turns out that the local sound speed (Mach number) of any gas is affected by pressure, temperature, and density... And guess what, a nozzle varies pressure and temperature along its whole length! Now the math starts to pick up in complexity! First, we have to determine the temperature of the gas in the nozzle throat (Tthroat). That is because, as explained above, the gas temperature at the nozzle throat is less than in the combustion chamber due to loss of some thermal energy during the acceleration of the gas to local speed of sound (Mach number = 1) at the throat. Gamma (the Y shaped Greek letter) is the ratio of gas specific heats, a dimensionless value (much like the Mach number), which relates to the heat capacity at a given volume for a gas. For the products of hydrocarbons and gaseous oxygen combustion, Gamma equals 1.2 Tgas = 1 / (1 + ((1.2-1)/2)) Tgas = 0.90909090909 of the Chamber temp. Tgas = 0.90909 * 3155 º K Tgas = 2868.18 º K or 2595 ºc The chamber (combustion) temperature is determined for this propellant combination from Table 1. Now, we have to determine the gas pressure at the nozzle throat.The pressure at the nozzle throat is less than in the combustion chamber due to acceleration of the gas to the local speed of sound (Mach number =1) at the throat, as given by So, Pgas = 300 psi * (1+((1.2-1)/2)) ^-(1.2 / (1.2 – 1)) I just rage-quitted there, and cheated with Wolfram Alpha. (which, by the way, is a wonderful free online tool that I recommend you check out) So, pressure at the throat is 169.34 psi. Quite a large drop, about half of the initial value, which is to be expected in this kind of nozzle. So far, so good. Also, the gas will have to be expanded to atmospheric pressure before exiting the engine. This is important for future calculations. Given that I live at 2700 ft above sea level, I just asked Wolfram Alpha which was the atmospheric pressure at that altitude. Unfortunately, time is in short availability for me right now. So, I give you the current status of our calculations. ENGINE MASTER DATA TABLE Parameter Value Metric Imperial Propellants GOX/Methanol Thrust 10.2kg 22.5 lbf Chamber Pressure 2.068 Mpa 300 psi Maximum Reaction Temperature 3155ºK 5679 ºR Mix ratio 1.2 ISP 248 s Expansion pressure 918 Mb 13.31 psi Total Mass Flow 41.1 gr/s 0.0906 lb/s Mass Flow (Oxidizer) 22.42 gr/s 0.049428 lb/s Mass Flow (Fuel) 18.68 gr/s 0.041182 lb/s Gamma 1.2 Throat Gas Temperature 2868.18ºK 5679 ºR Throat Gas Pressure 1.168 Mpa 169.34 psi Please join me in the next installment, when we determine Mach numbers and finally some physical dimensions! Until then, if you find any errors or have comments/suggestions, please do let me know. Thanks. Dec 18 2015: Hey! Real life has been hell these days! Fortunately, now I've had time to review another part of the design. Onward! Now that the gas parameters, such as temperature and pressure at the throat have been determined, and we know the mass flow of the engine, we can proceed to calculate throat area, and from that, derive throat diameter (The first physical dimension) Throat area is given by: Where R is the universal gas constant, M is the molecular weight of the exhaust gasses, and Gc is the universal gravitation constant. Athroat = ((Mflow/Pthroat) * ((R * Tthroat ) / (Gamma * gravitational constant)) ^1/2 Athroat = (0.0906 lb/sec / 169.34 psi) * ((64.388 foot-pound/pound/degree Rankine * 5679 degrees Rankine)/ (1.2 * 32.2 foot/sec^2 )) ^1/2 Athroat = (0.0906 lb/sec / 169.34 psi) * ((64.388 foot-pound/pound/degree Rankine * 5679 degrees Rankine )/ (1.2 * 32.2 foot/sec ^2 )) ^1/2 Athroat = (0.0906/169.34 psi) * ((64.388 *5679)/ (1.2*32.2)) ^1/2 Athroat = (0.0906/169.34 psi) * (365659.452 / 38.64) ^1/2 Athroat = (0.0906/169.34) * (365659.452 / 38.64) ^1/2 Athroat = (0.0906/169.34) * (365659.452 / 38.64) ^1/2 Athroat = 0.0520461 square inches, or 33.5781 square mm Given this area, we can proceed to determine diameter, by simple geometry of circles. Dthroat= 4*33.5781 / 3.14159265 Dthroat= 4*33.5781 / 3.14159265 Dthroat= 6.53858 mm I'm sorry guys, I really wanted to push out more content today but an unexpected work issue has arisen (yet again) *Sigh*.. I'll have a fuller update ASAP. Sorry for the really crappy little update, but hey, progress is progress! PS: Almost forgot, this is our Data Table now: ENGINE MASTER DATA TABLE Parameter Value Metric Imperial Propellants GOX/Methanol Thrust 10.2kg 22.5 lbf Chamber Pressure 2.068 Mpa 300 psi Maximum Reaction Temperature 3155ºK 5679 ºR Mix ratio 1.2 ISP 248 s Expansion pressure 918 Mb 13.31 psi Total Mass Flow 41.1 gr/s 0.0906 lb/s Mass Flow (Oxidizer) 22.42 gr/s 0.049428 lb/s Mass Flow (Fuel) 18.68 gr/s 0.041182 lb/s Gamma 1.2 Throat Gas Temperature 2868.18ºK 5679 ºR Throat Gas Pressure 1.168 Mpa 169.34 psi Throat Area 33.5781 mm2 0.0520461“2 Throat Diameter 6.53858 mm 0,2574244 “ Feb 18 2015: Hello guys! Sorry I left all of you hanging in there, but I've been having all kinds of Real Life Stuff™ going on! I can't promise updates will be regular anymore, but this project is in no way shelved or anything. In the last installment, we had determined the gas pressure, temperature, and throat area of the nozzle. Now, with that data on hand, we can proceed to calculate the best bell end diameter that will provide expansion to the desired pressure and prevent the engine from running under or overexpanded. (Don't worry, I'll explain these terms in a second) In order for us to understand why expanding to a predetermined pressure is important, you have to go back to the definition of a DeLaval nozzle that I posted some paragraphs above. "The idea behind a DeLaval nozzle [...] is to transform a high pressure, high temperature, low velocity gas, like the combustion products, into a low pressure, relatively low temperature, and crazy-high speed gas." So the nozzle does useful work (accelerating a gas) by taking energy from its heat while reducing its pressure. I never even thought this would be significant, I mean, the larger the expansion, the better the performance you extract from the engine, right? But as a thought experiment, I decided to imagine the "perfect" engine. This perfect engine would have an infinitely large exhaust nozzle, it would drop the exhaust pressure to zero and the exhaust temperature to absolute zero, and thereby convert all the available heat from the exhaust gasses into kinetic energy. Exhaust velocity would NOT be infinite, because there's only a limited amount of heat energy to begin with, and, given the infinitely large nozzle would also be infinitely heavy, that would render our perfect engine useless, but hey, this is only a thought experiment in a perfect vacuum... And then it hit me, that in fact a real engine would not operate in a perfect vacuum, where the ideal exhaust pressure is zero, but it would operate inside an atmosphere, where the ideal expansion is to atmospheric pressure. To better understand why this is so: Imagine you are sitting with your engine at sea level. Therefore, the pressure of the engine exterior is 1 atmosphere, or 14.7 psi. Now imagine you had 300 psi in the combustion chamber, and your hypothetical nozzle had been designed to reduce pressure at the exit to 100 psi. So, what happens when you start said engine? Your nozzle works as expected, and it reduces exhaust pressure to 100 psi, with a proportional temperature drop. Then, once the gasses leave the nozzle, what happens? They immediately proceed to expand to 14.7 psi, further cooling in the process. Therefore your nozzle is underexpanded, and it is wasting gas energy (Remember, any gas that expands outside the engine is useless for thrust, much like excess fuel would be (There is an exception to that if running fuel-rich reduces the molecular weight of your exhaust, such as in hydrogen/oxygen burning engines, but that is honestly beyond the scope of this discussion)). Now to the opposite end of the spectrum: Imagine you take the same engine and change the nozzle for one that goes to, say, 0.5 psi. As the gasses go further down the nozzle, their pressure will decrease, until it matches that of the atmosphere. At said point, they stop expanding, because the atmospheric pressure exerts a force equal and opposite to that of the inner gas pressure, and the exhaust will form a column that is "pinched" by the atmosphere and will exit the bell without expanding any further. This seems like it would be good enough, right? You get a slightly larger and heavier nozzle, but for that price, you make absolutely sure that you're expanding the gas as much as it can expand, and getting all the thermal and pressure energy you can get out of it. The exhaust is as cool as it can get, it's at ambient pressure, and you've extracted all the velocity you can extract. Then who cares if the nozzle is a bit too large? Well, in an ideal world that would be OK, but in the real world, having parts of the nozzle not filled with exhaust is a bad, bad idea. The best that can happen is that the gas "sticks" to the nozzle walls after its expansion is done, you get vacuum "bubbles", Mach diamonds, turbulence, etc. in the exhaust and you lose thrust. (That happens with mild overexpansions) and the worst that can happen is the flame flopping around like crazy and banging the nozzle walls randomly until the vibration, noise, and mechanical stress of the turbulent gas flow cause the engine to experience R.U.D. (Rapid Unscheduled Disassembly) Real rockets have a problem with that. Especially first stages! First stages have to go from sea level to almost a vacuum! So how do they avoid gross underexpansion or overexpansion? Well, by compromising, and using a nozzle that is designed to work halfway between sea level and vacuum. So upon start up they are overexpanded, and as they climb they reach their design altitude (perfectly expanded), and then past that they become underexpanded. Example overexpanded nozzle. You can see the telltale Mach disks. And my favorite underexpanded one, Saturn V going uphill You can check out the expansion of exhaust gasses in this video of the Mars Climate Orbiter launch. Check out how big that plume gets as the atmosphere gets thinner and thinner. That was when I came across what I thought was the simplest engine design calculation so far: With said constant already being helpfully provided by the author. But alas, I'm always curious, and I dived into Rocket Propulsion Elements, to find out why relative gas expansion was so simple. Oh, how I was to repent. Turns out, said constant is only valid for sea level. For expansion to a different pressure, you need either a new constant, or you need to do math of the kind that gives you chills. Nevertheless, once I was in, i had no choice but to press forward (Just kidding, I had fun learning about it) These equations will be used to calculate the Mach speed of the exhaust gasses, and once we have that, find an exhaust area that will yield exhaust pressure equal to the local atmospheric pressure for that Mach number. Once again, Wolfram Alpha proves to be an invaluable tool for the hobbyst rocket engineer who wants to save time and headache. An exhaust velocity of Mach 2.62 sounds incredibly high, but actually, is pretty much on the lowest end of what you will get with a rocket engine. Now that we know the area of the nozzle end, we can use simple circle geometry to calculate a diameter (It's the same formula we already used to derive nozzle throat diameter from nozzle throat area) Dexhaust=0.515609 inches or 13.0965 mm. Therefore our Master Data table now looks like this: ENGINE MASTER DATA TABLE Parameter Value Metric Imperial Propellants GOX/Methanol Thrust 10.2kg 22.5 lbf Chamber Pressure 2.068 Mpa 300 psi Maximum Reaction Temperature 3155ºK 5679 ºR Mix ratio 1.2 ISP 248 s Expansion pressure 918 Mb 13.31 psi Total Mass Flow 41.1 gr/s 0.0906 lb/s Mass Flow (Oxidizer) 22.42 gr/s 0.049428 lb/s Mass Flow (Fuel) 18.68 gr/s 0.041182 lb/s Gamma 1.2 Throat Gas Temperature 2868.18ºK 5679 ºR Throat Gas Pressure 1.168 Mpa 169.34 psi Throat Area 33.5781 mm2 0.0520461 “2 Throat Diameter 6.53858 mm 0,2574244 “ Exhaust gas velocity (Mach) 2.62167 Nozzle exit area 134.71 mm2 0.2088 “2 Nozzle exit diameter 13.0965 mm 0.515609 “ Join me in the next installment, where we'll calculate the combustion chamber parameters, and we will be then ready to begin sketching the innards of the chamber + nozzle. Until then, thanks for your time & patience in dealing with my ramblings, and as always, if you find a mistake, please DO let me know. I happen to dislike explosions if I have to pay for the exploding stuff. Mar 3 2015: Hi! Finally found a bit of free time! Real Life keeps me busy, and usually at the end of the day I'm too knackered to do anything other than crawl into bed .... But enough of my whining! You're here for the possible explosions rocket engine design theory. Given that we now know the throat diameter, and exit diameter, one would think that it's already time to calculate nozzle inlet diameter, but, a quick bit of thinking reveals that the nozzle inlet and chamber outlet are one and the same, so we'll kill two birds with a single stone, and calculate chamber dimensions which we can then use to derive nozzle inlet diameter. We will start by calculating the volume of the chamber, and, knowing that volume, we can make an educated guess about length/diameter ratio, and calculate exact values from there. What would a good volume be? A good volume would be one that ensures adequate mixing, evaporation, and complete combustion of propellants by the time they reach the nozzle inlet. That is so, because the nozzle is designed to work with a specific inlet pressure and temperature. Any propellant that goes past the nozzle inlet, will probably burn in the nozzle, which is a bad idea because temperatures at the throat are already pretty critical (despite being at lower temperatures, the throat is the area with less dissipation surface available, and therefore more susceptible to heat damage) and also it would throw off our pressure and temperature ratios for all the points along the nozzle, and if the chamber is too big, the gasses will have time to cool before they enter the inlet, thus reducing engine performance. So, in resume: Chamber too big: Colder inlet temperatures, performance wasted. Heavier engine. Somewhat easier cooling due to lowered gas temps at the nozzle. Risk of combustion instability. Chamber too small: Dangerously hotter nozzle, performance wasted. Lighter engine. Calculating the aerothermochemodynamics of complex hydrocarbons reacting while changing their state, pressure, mixture ratios, temperature, movement speed, and several other variables, in order to ensure complete combustion, is an awful, hellish nightmare. Trust me, I have looked at it. But turns out, there's a cheat for that. Even Real Life Rocket Scientists™ happen to use it for preliminary designs. It's called "characteristic chamber length" and is defined as the length that a chamber of the same volume should have if it were a straight tube and had no converging nozzle section. Characteristic chamber length, L* or L star, is determined experimentally for different propellant combinations, throat diameter, and combustion pressures, and it can be sourced from tables. For an hydrocarbon burning engine like mine, L* is between 50 to 70 inches. The variation is to account for injector design (propellant mixing) I decided to go with 60 inches. Vchamber = 60 * 0.0520461 cubic inches, therefore Vchamber = 3.122766 in3 or 51.173 cm3 To derive chamber length from volume, we also have to know a diameter. A good diameter for combustion chambers is around 5 times throat diameter. Dc = 5 Dthroat Dc = 5 * 6.53858 Dc = 32.6929 mm – 1.287122 inches This is for the cylindrical portion of the chamber. For a small chamber, we can just assume the convergent segment to be 1/10th of the chamber volume, and be done with it. For the chamber area, i just went with my trusty ally, Wolfram Alpha. Lc = Vc / (1.1 * Ac) Lc = 3.122766 in3 / (1.1 * 1.3012 in2) Lc = 3.122766 / (1.1 * 1.3012) Lc = 3.122766 / 1.43132 = 2.18174 inches - 55,416196 mm And thus, our Engine Master Data Table is beginning to fill with physical dimensions. ENGINE MASTER DATA TABLE Parameter Value Metric Imperial Propellants GOX/Methanol Thrust 10.2kg 22.5 lbf Chamber Pressure 2.068 Mpa 300 psi Maximum Reaction Temperature 3155ºK 5679 ºR Mix ratio 1.2 ISP 248 s Expansion pressure 918 Mb 13.31 psi Total Mass Flow 41.1 gr/s 0.0906 lb/s Mass Flow (Oxidizer) 22.42 gr/s 0.049428 lb/s Mass Flow (Fuel) 18.68 gr/s 0.041182 lb/s Gamma 1.2 Throat Gas Temperature 2868.18ºK 5679 ºR Throat Gas Pressure 1.168 Mpa 169.34 psi Throat Area 33.5781 mm2 0.0520461 “2 Throat Diameter 6.53858 mm 0,2574244 “ Exhaust gas velocity (Mach) 2.62167 Nozzle exit area 134.71 mm2 0.2088 “2 Nozzle exit diameter 13.0965 mm 0.515609 “ Chamber Volume 51.173 Cm3 3.122766 “3 Chamber Diameter 32.6929 mm 1.287122 ” Chamber Area 839.5 mm2 1.3012 “2 Chamber Length (including Convergent Segment) 55,416196 mm 2.18174” Please join me next time, were we'll calculate chamber walls, dabble in safety margins, and make a first crude sketch of the engine (Spoiler: It does end up looking like a rocket engine) Until then, if you happen to find any errors, or have feedback, please do so. Thanks Apr 30 2016: Wow! It's been a long time! Sorry for the delay guys... Real life has been absolutely hectic, work issues, study issues, family issues, you name it you got it! Despite the long time between updates this project is not dead at all and I've been itching to show some of the progress I've made. So, without further ado, let's dive in! In the last installment, we had finished determining chamber and nozzle dimensions, but these are the inside ones only, and now we will calculate wall thickness. Every point in the chamber and nozzle has to be strong enough to resist the pressures involved, otherwise the engine will explode. I've decided that, in order to simplify the design, I will simply use a constant wall thickness, suited for the highest pressure area. This is really overkill for parts of the nozzle where the pressure will be lower, and makes the engine significantly heavier, but greatly simplifies both design and machining. Thus I shall design a vessel that can contain 300 psi with an adequate safety margin. Given that the nozzle will be automatically overbuilt, due to its lower operating pressure, I will treat the chamber as a pipe and thus greatly simplify calculation. The equation for the stress on the wall of a tube is: where S is the stress on the pipe wall, P is Pressure, D is Diameter and Tw is the wall thickness. Thus, if we replace S with the ultimate strength of our material, we can calculate the minimum wall thickness. I choose copper, given that it has excellent thermal conductivity, is easy to machine, and is cheap. The ultimate strength of copper is around 10.000 psi, but I will use a conservative 8000 psi in this calculation. S= P * D / 2Tw Tw = P * D / 2S Tw = 300 psi * 1.287122 inch / 16000 Tw = 300 * 1.287122 /16000 Tw = 0.0241335375 inch or 0.61299185 mm Of course this is the absolute minimum value, and while going with 2 mm wall thickness should be more than enough, there are other things to consider, machinability being a top priority since I don't want this project to be unnecessarily hard to machine (Machining a nozzle with walls of that thickness, in copper, will be very hard to do without deforming it) Therefore, I will make an educated guess and use a 5 mm wall thickness, which should be easy to obtain. That also gives me an 815% safety margin. This baby may melt, but an explosion is now an extremely unlikely outcome. (Thankfully) Obviously this just made the engine a lot heavier, but, then again, I don't care about weight. Now that we know all our dimensions, we need to determine our half angles, or the angles of the lines that join inlet, throat, and outlet, thus conforming the nozzle walls. For this small engine, adding a bell shape would give me major machining headaches, and produce only a minor performance improvement. Based on a simpler geometry proposal by @A Fuzzy Velociraptor, I decided to go with 15º and 40º half angles, jointed by rounded unions. I proceeded to fire up my favorite CAD software and did a quick sketch. (All dimensions in mm) I don't know about you, but to me, that definitely looks like a rocket engine. What do you guys think? Next up: We will tackle the issue of cooling. Hopefully tomorrow. No promises. ENGINE MASTER DATA TABLE Parameter Value Metric Imperial Propellants GOX/Metanol Thrust 10.2kg 22.5 lbf Chamber Pressure 2.068 Mpa 300 psi Maximum Reaction Temperature 3155ºK 5679 ºR Mix ratio 1.2 ISP 248 s Expansion pressure 918 Mb 13.31 psi Total Mass Flow 41.1 gr/s 0.0906 lb/s Mass Flow (Oxidizer) 22.42 gr/s 0.049428 lb/s Mass Flow (Fuel) 18.68 gr/s 0.041182 lb/s Gamma 1.2 Throat Gas Temperature 2868.18ºK 5679 ºR Throat Gas Pressure 1.168 Mpa 169.34 psi Throat Area 33.5781 mm2 0.0520461 “2 Throat Diameter 6.53858 mm 0,2574244 “ Exhaust gas velocity (Mach) 2.62167 Nozzle exit area 134.71 mm2 0.2088 “2 Nozzle exit diameter 13.0965 mm 0.515609 “ Chamber Volume 51.173 Cm3 3.122766 “3 Chamber Diameter 32.6929 mm 1.287122 ” Chamber Area 839.5 mm2 1.3012 “2 Chamber Length + Convergent segment 55,416196 mm 2.18174” Chamber Wall thickness 5 mm 0,19685” Nozzle Half-Angle 15º Nozzle inlet Half-angle 40º May 06 2016: Did I say tomorrow? I totally meant in a week or so! Let's get started on cooling, shall we? In order to understand the cooling needs, we first have to understand how the heat flows through a rocket engine. Most of the heat of combustion is either used up accelerating the gasses, or leaves with the exhaust, while a part of it is transferred to the chamber wall, propellant injectors, and nozzle. Heating is a problem because it can debilitate the metals of the chamber to the point at which they cannot resist the chamber pressure anymore, causing deformations which are usually followed by RUD. Therefore, we can devise of several methods to keep the temperatures within reason. No cooling at all: Use the thermal mass of the engine as a heat sink, then radiate the heat away while the engine is off. Pros: Simplest method - Cons: Run time very constrained. Passive cooling: Use either the engine nozzle or chamber walls exposed to the atmosphere as radiators. Pros: Very reliable - Cons: Complex design, a large run time requires more radiating surface than may be available, and thus, the run time is still limited without adding heavy radiator vanes. Active cooling: Use a cooling fluid circulated against the walls to get heat out of the engine. Pros: Unlimited run time. Potential to be extremely lightweight, if regenerative cooling is used (Regenerative cooling means that propellant doubles as cooling fluid) Cons: Complex design. I shall use Active cooling for this engine, for the following reasons: Safety I: If I design the engine for unlimited run time, the chance of destroying it in a 5 second initial run is extremely low. Safety II: The cooling jacket doubles as a shrapnel shield, and protects the test stand equipment from a possible explosion. It should be an interesting and educative challenge, but not a hardcore one like regenerative cooling. Active cooling works like this: (in this example, the cooling fluid is water) Small hobby rocket engines have an average heat transfer from the hot gasses to the chamber walls of about 0.5 Kw/cm2/sec, or 3Btu/sq inch./sec. Therefore, and assuming a perfect wall conductivity, this is the amount of heat that has to be removed from each square cm of the engine. Now in order to know the total heat transfer per unit time, we have to determine the inner surface area. In order to simplify calculation, I will ignore fillets and treat the engine as a cylinder for the chamber, a truncated cone for the nozzle's convergent section, and another truncated cone for the divergent section. Atotal= Achamber + Anozzle convergent + Anozzle divergent The formula for the surface area of a cylinder is: I shall modify this formula, because I do not want the total area, I only want the area of the side wall + top (the injector plate) The bottom area is shared with the convergent section of the nozzle and there is no material there to absorb heat. Therefore, Achamber = 2 * 3.14159265359 * 16.345 ^ 2 + 2 * 3.14159265359 * 16.345 * 40 So, the area of the chamber inner side walls plus injector plate inner side: Achamber = 5786 sq milimeters. The lateral area of a truncated cone, is as given by: Thus, for the convergent segment of our nozzle, Anozzle c = 3.14159265359 * (16.345 + 3.408) * Sqrt ( (16.345 - 3.408)^2 + 15.838) We use lateral area because the "bottom" of the truncated cone is the chamber radius and is not in contact with the walls, and the "top" is the throat radius, and, as such, also not in contact with walls. Therefore, Anozzle c = 840 sq mm And now, the same for Anozzle d Atotal= Achamber + Anozzle c + Anozzle d Atotal= 5786+ 840 + 145 Atotal= 5786+ 840 + 145 = 6771 square mm, or 67.71 square cm, or 10.5 square inches. The total heat transfer, "Q", is equal to the heat transfer rate "q" times the surface area of the inner walls. Therefore Q = qA Q = 0.5Kw/cm2/sec * 67.71 cm2 And thus, the total heat transfer of the engine is 33.85 Kw, or about 45 horsepower... (For the Imperial guys, about 31.5 BTU/sec) Join me next time, when we will attempt to find out exactly how much water flow does it take to get these insane amounts of heat out of the engine! If such a small engine produces these amounts of heat, my respect for the guys and gals that work on the real deal with regenerative cooling has multiplied hundredfold. May 16 2016 A few days ago, we calculated the amount of waste heat that the engine would output when working, and now we need to devise a means to get said heat out of the engine, in order to keep the operating temperatures as low as possible. Injector cooling is not an issue, as they are cooled by the inflow of propellant. Injector plate and chamber, however, are. For the sake of simplicity, I will stick to using water as coolant. Therefore, the system now has a few defined constraints: The coolant fluid must not boil. I will use water as coolant, for its high specific heat, and availability The system must be more capable than strictly needed. I don't care about mass and therefore I will have ample safety margins. Coolant flow speed of 10 m/sec or around 30 fps The coolant shall enter near the nozzle, flow all the way around the chamber, and leave near the injector plate. The amount of water mass flow (mass/sec) needed can be calculated, given the desired temperature rise and the heat input to the fluid, as given by: This is a simplified equation that only will work for water. For other cooling fluids, you need to factor in specific heat capacity. A good ΔT could be 20 ºC, that way water entering the cooling system at ambient temperature, about 20 ºC, would leave at 40 ºC, and thus a 60 ºC margin would remain before its boiling point. (68 to 108 ºF, 42.22ºF ΔT,) Wm = 31.5 / 40 Wm = 0.7875 pounds/sec, or 357 grams/second of coolant fluid. Another cool thing about using water is that, given a density (σ) of 1kg/lt, we now also know that the engine will need 0.357 liters of water per second in order to operate. (That is around 21.5 liters per minute, or 1290 liters per hour.) Now we have to calculate a pipe of such area as to obtain the desired water flow at the desired flow velocity (10 m/s should be more than enough to prevent boiling for this engine). To simplify calculation, I will treat water as a perfectly incompressible fluid. To obtain the desired mass flow at the desired velocity, the cooling jacket must have an area Ajacket, given by: The cooling jacket will therefore be like a ring around the outside of the chamber walls, with cross-sectional area Ajacket , as given by: where D2 is the inner diameter of the outer jacket and D1 is the outer diameter of the combustion chamber, given by: D1 = Dc +2Tw Where Dc is Chamber inner diameter and Tw is the wall thickness. Now we substitute and solve as this: And thus: D2 = sqrt(4mw/(Vw ^ density ^pi) + D1 ^2) D2 = sqrt(4*0.357kg /(10 m/s ^ 1 kg/lt ^3.14159265359) + 42.69 ^2 ) So, 44.33 mm is the inner diameter of the cooling jacket. I will just round it up to 46 mm for ease of machinability. That will increase coolant consumption without significantly improving cooling, but I don't care about that. Please join me in the next installment, when we finish up the coolant jacket design, including yet again safety margins, and some weird math! Until then, I leave you our ENGINE MASTER DATA TABLE Parameter Value Metric Imperial Propellants GOX/Metanol Thrust 10.2kg 22.5 lbf Chamber Pressure 2068 kpa 300 psi Maximum Reaction Temperature 3155ºK 5679 ºR Mix ratio 1.2 ISP 248 s Expansion pressure 918 Mb 13.31 psi Total Mass Flow 41.1 gr/s 0.0906 lb/s Mass Flow (Oxidizer) 22.42 gr/s 0.049428 lb/s Mass Flow (Fuel) 18.68 gr/s 0.041182 lb/s Gamma 1.2 Throat Gas Temperature 2868.18ºK 5679 ºR Throat Gas Pressure 1168 kpa 169.34 psi Throat Area 33.5781 mm2 0.0520461 “2 Throat Diameter 6.53858 mm 0,2574244 “ Exhaust gas velocity (Mach) 2.62167 Nozzle exit area 134.71 mm2 0.2088 “2 Nozzle exit diameter 13.0965 mm 0.515609 “ Chamber Volume 51.173 cm3 3.122766 “3 Chamber Diameter 32.6929 mm 1.287122 ” Chamber Area 839.5 mm2 1.3012 “2 Chamber Length + Convergent segment 55,416196 mm 2.18174 ” Chamber Wall thickness 5 mm 0,19685” Nozzle Half-Angle 15º Nozzle inlet Half-angle 40º Average wall heat transfer 0.5 kw/sec/cm2 3 Btu/sec/“2 Total inner surface area 67.71 cm2 10.5“2 Total heat transfer 33.85 kw/sec Coolant fluid Water Coolant fluid ΔT 20º C 42.22º F Coolant mass flow 357 grams/sec 0.7875 lb/sec Coolant flow volume 0.357 liters/sec 12.07 fl oz/sec Coolant density 1kg/lt 62.43 lb/ft3 Coolant flow velocity 10 m/s 32.81 ft/sec Coolant jacket inner diameter 46 mm 1.811” June 29 2016 Man, time sure flies when you're having fun horribly busy! On with the show! In the last installment, we had almost finished the cooling jacket, but some dimensions still have to be known, such as jacket inlet/outlet diameters, and jacket wall thickness. I shall use a single outlet, and two offset inlets, in order to produce a swirling motion of the coolant that should help prevent hot spots. In order to avoid pressure variations, and to keep flow speed constant, I shall keep a constant area between inlets, jacket, and outlet. The jacket has to withstand the coolant pressure, but it also doubles as shrapnel shield in case of engine RUD, and thus I will simply go for an overkill 5 mm wall thickness for the jacket, which gives us an outer diameter of 56 mm. The area of the inlets equals 1/2 of the area between the chamber outside wall and the jacket inner wall. This, as given by the area of a circle formula, equals 5221 mm2 for the jacket, and 4499 mm2 for the chamber. Thus, the coolant flow passage area is 722 mm2. and the outlet is 3.032 cm in diameter, while the inlets are half that. I'll just round it to 30 and 15 mm, for ease of machining. I'm starting to feel that the extra area I've added is counterproductive, as the design might be wasteful of water. Although better safe than sorry. I'll stick to those dimensions, and if there's excessive cooling I can simply reduce flow. And with that, the cooling design is done. Next up: Injectors! Oh boy! ENGINE MASTER DATA TABLE Parameter Value Metric Imperial Propellants GOX/Metanol Thrust 10.2kg 22.5 lbf Chamber Pressure 2068 kpa 300 psi Maximum Reaction Temperature 3155ºK 5679 ºR Mix ratio 1.2 ISP 248 s Expansion pressure 918 Mb 13.31 psi Total Mass Flow 41.1 gr/s 0.0906 lb/s Mass Flow (Oxidizer) 22.42 gr/s 0.049428 lb/s Mass Flow (Fuel) 18.68 gr/s 0.041182 lb/s Gamma 1.2 Throat Gas Temperature 2868.18ºK 5679 ºR Throat Gas Pressure 1168 kpa 169.34 psi Throat Area 33.5781 mm2 0.0520461 “2 Throat Diameter 6.53858 mm 0,2574244 “ Exhaust gas velocity (Mach) 2.62167 Nozzle exit area 134.71 mm2 0.2088 “2 Nozzle exit diameter 13.0965 mm 0.515609 “ Chamber Volume 51.173 cm3 3.122766 “3 Chamber Diameter 32.6929 mm 1.287122 ” Chamber Area 839.5 mm2 1.3012 “2 Chamber Length + Convergent segment 55,416196 mm 2.18174 ” Chamber Wall thickness 5 mm 0,19685” Nozzle Half-Angle 15º Nozzle inlet Half-angle 40º Average wall heat transfer 0.5 kw/sec/cm2 3 Btu/sec/“2 Total inner surface area 67.71 cm2 10.5“2 Total heat transfer 33.85 kw/sec Coolant fluid Water Coolant fluid ΔT 20º C 42.22º F Coolant mass flow 357 grams/sec 0.7875 lb/sec Coolant flow volume 0.357 liters/sec 12.07 fl oz/sec Coolant density 1kg/lt 62.43 lb/ft3 Coolant flow velocity 10 m/s 32.81 ft/sec Coolant jacket inner diameter 46 mm 1.811” Coolant flow passage area 722 mm2 1.119”2 Coolant inlets diameter 15 mm 0.5906” Coolant outlet diameter 30 mm 1.181” Mar 10 2017: Not abandoned! It may take me a long time, but this project will be finished come hell or high water! It's been a long time, so I'd recommend that you read from the beginning as a refresher. With that said, let's proceed. So, where was I? Ah, yes, injectors, injectors. The function of an injector is to take high pressure propellants from the feed lines, meter the appropriate amount of each (much like a carburetor), and inject them into the chamber in such a way that they can properly and efficiently burn. There are several kinds of injectors, impinging, showerhead, hollow post, pintle, etc. For this design, I shall use an impinging design. It's easy to design and build, and, while it has several disadvantages (Less efficient, very hard to throttle, small variations in shape cause big mixture irregularities, etc), these disadvantages are irrelevant to the type of engine that I'm designing. There are several "eyeballed" parameters. 100 PSI pressure drop. This should be enough to help prevent instability without requiring structural reinforcement. 20 m/s injection velocity. I was unable to find data on how an injection velocity is chosen for different propellants, however, this value is mid of the range for small hydrocarbon/oxygen engines We can now proceed to determine injector hole area, based on the physical characteristics of the propellants. Ethanol can for all practical purposes be considered incompressible. Thus, the injection area that satisfies the mass flow and injection characteristics is given by Where m is the propellant flow mass, c is the discharge coefficient, δ the density, and Δp the pressure drop. A typical discharge coefficient for round hole, small size injectors with a larger fuel manifold behind is about 0.7 The density of ethanol is about 0.75 g/cm3 at ambient pressure, and almost does not change with pressure. Pressure drop will be 100 psi. And also the bibliography I'm using (For those of you crazy cool enough to attempt a similar project) Title Author Editor DESIGN OF LIQUID PROPELLANT ROCKET ENGINES Dieter K. Huzel and David H. Huang Rocketdyne Division, North American Aviation HOW to DESIGN, BUILD and TEST SMALL LIQUID-FUEL ROCKET ENGINES Leroy J. Krzycki ROCKETLAB / CHINA LAKE, CALIFORNIA MECHANICS AND THERMODYNAMICS OF PROPULSION Philip G. Hill and Carl R. Peterson Addison-Wesley Publishing Company Ignition!: An informal history of liquid rocket propellants John D. Clark Rocket Propulsion Elements 7th Edition GEORGE P. SUTTON and OSCAR BIBLARZ JOHN WILEY & SONS, INC If you have any insight, questions, or even better, have found an error, please let me know
  12. I'm literally never going back again, this is probably the hardest challenge in any game i've ever played. No real point here just venting, went through about 20 ship designs, last one made it to 14k then ran out of fuel. Didn't even get past the first layer of the atmosphere
  13. The KSP Moderation Team is proud to present Threads of the Month Awards, for July 2019! We have an embarrassment of riches this month as the new updates and expansions are bringing out the excitement and creativity of our forum members. There's so much good stuff that we're holding some of the nominations over for next month so that all the selections get a turn in the spotlight. The first winner this month is @Brikoleur with his very informative and well written helicopter tutorial. @ManEatingApe and the contributors to this thread are flinging kerbals for fun and science. Next up is @HippieGold with a Kraken rousing examination of the KSP physics involved in building a space elevator. If you've ever wondered how high a robotic frog can jump on Gilly, @Klapaucius has got you covered. @benjee10 is working on an impressive Shuttle parts pack that surely will become a mandatory mod for STS enthusiasts. Finally we would like to give a special thanks to @VITAS who has built and maintained the SpaceDock mod hosting website for many years. Your work in service of the community is much appreciated. Congratulations to all for your wonderful contributions and please remember to report a thread (add the comment 'totm') or PM a moderator if you feel it is worthy of thread of the month. Special thanks go to @woeller, @4x4cheesecake @Nigel J. Cardozo and @fourfa for your nominations. All winners are free to add the Thread of the Month badge (created by our very own @adsii1970) to their posts, signatures or have it painted on their lounge room wall, provided they own the residence outright and use non volatile organic compound paints.
  14. This craft is a 1:1 scale full stock replica of the H-4 Hercules, more popularly known as the Spruce Goose. This craft, while relatively simple in its design, ended up being one of my more involved replicas, with a large amount of work and experimentation put into replicating the design. The craft is powered entirely by 8 of my R-4360 turboprops, which combined produce 3200 kN of thrust. The wings of this replica represent my first attempt at fully constructing a custom aerofoil. The technique used is effective, but I have since improved upon it,and you can expect more advanced versions of it in my future replicas. One interesting quirk of these wings, is that the enormous amount of drag and lift they produce means that this craft flies very smoothly at its top speed of 26 m/s, yup. Performance wise, this craft did not meet up to my expectations. I had intended for this craft to be capable of water takeoff and landing. With this in mind I kept the craft as light as possible, being about half the weight of my other replicas of similar size and complexity. Unfortunately, this craft was not able to land, nor take off from the water, meaning that this replica is basically completely aesthetic. While I am somewhat disappointed by this craft, I learned a great deal whilst making it, and it was ultimately a valuable experience. Download: https://kerbalx.com/Kronus_Aerospace/Kronus-H-4-Hercules-Spruce-Goose Craft Mass: 310.95 tonnes Part Count: 2141 parts I would love any suggestions about what *big* plane I should build next!
  15. UPDATE - 05/07/2019 Let's add more digits! We now we have two, two-digit inputs with a three-digit output. We've about tripled the number of gates. We're at about 700 parts now instead of the 250 earlier. I used a wonderful, free program called Logisim to help me get my logic correct before I began the upgrade. You'll see in a few places there are two NOT gates attached, which shouldn't make sense. But being mechanical this NOT/NOT arrangement gave me leeway and space to move and reposition those logic segments so everything lined up. I'm probably gonna stop here though. Since gravity is the ground state each lower gate has to weight whatever is above it +1, so it adds (lol) up quickly. As this thing gets bigger it gets way harder to build and troubleshoot too. Thanks everybody. ------------------------------------ Why do we build stuff? Because we can. Like some of my other useless craft this is more just to say, 'Welp, it's possible.' I'm not proud of all the floating parts, but having it stretched out made troubleshooting easier and I didn't want gates hitting each other. I spend lots of time with google and wikipedia learning about logic gates, truth tables, half and full adders, and how to make gates out of other gates. So this thing takes takes two single-digit binary numbers, adds them together, and gives a sum in base 2. The logic gate NOR is universal and can be used to replicate all other gates. All gates can probably be made in KSP, but I've only used 2 of the easiest for simplicity. I have NOT gates and OR gates, which combined make NOR, so we can perform all functions with combinations of these 2. See mom, video games and the internet are good for me. The are only 2 actuators, buttons 1 and 2, for the 2 airbrakes you see. They manipulate the input to the first NOT and OR gates and change the bottom display. The top display is calculated through the gates. Not sure if these pictures are gonna show enough but here we go The gates have 2 states, 0 or 1. 0 (inactive) is horizontal and 1 (active) is up 30 some degrees. Craft is set to default to 0 and 0 for inputs by gravity. Because it's mechanial you can't just run a wire to anywhere, so I had to find a configuration to get the last OR to work. Maybe in the future I can try to make different gates, or add more digits at the same time. Eat your heart out, Minecraft. KerbalX
  16. THE LIGHT FANTASTIC CHALLENGE Aerospace as art... I've been having fun playing with lights on my craft, and I wanted to see what others would come up with. So, the challenge is simple: Build a plane, sub, SSTO, lander, space station, orbiter etc and make it look amazing with LIGHTS. There are no restrictions at all on this challenge. GO NUTS!. Post photos, or even better yet, video of your craft. This is an example I built a while ago, but I plan to enter a new one in the challenge. (more examples under the hidden items).
  17. Yes, you heared right, I have made a fully stock - that means no DLC - version of the famous Lockeed L1049 Super Constellation complete with stock Props and build in 1:1 scale. All this with a farly moderate partcount of 628, well, moderate for that scale of plane. Dowload link: https://kerbalx.com/HB_Stratos/Lockheed-L-1049-Super-Constellation I liked the plane so much I´ve made a whole cinematic dedicated to this plane. If you skipped over it, please watch the Video above, It was a lot of work but truly worth it.
  18. This is a repost version, because the last one had some swear-words.
  19. I actually have no clue where this goes, so please move it if it's in the wrong spot. What a wonderful day it is, on the really old outdated and frankly nostalgic at this point launchpad, where a mission is about to take a place. A mission that will Make History and... Actually I'm pretty sure noone's going to jump at this. You can see the moon-Alright you know what, that's enough of that. If you wanna skip everything and just download the file, click here. This post is an absolute mess and I do not blame you for just wanting to skip most of it. If you want to read my ramblings, please continue on. I plan to clean up this post eventually, but it's 5 in the morning and I'm tired. Making Scenariory is (maybe? Probably? Unlikely?) the first user created scenario(not that it means much...) and it's what it says on the tin. A critique on the Stayputnik, and the absolute utter annoyance it is to not have SAS on it when literally EVERY OTHER UNMANNED COMMAND CORE THAT HAS EXISTED DOES. Ignoring my flash of anger there, critics will say that this scenario was designed to be the worst possible scenario in history, and then rudely ask you how the heck you got into their house and why your pants were down, but BAH, what do they know about art? They're not the artists, I'm the artist! I've gone through the effort to make the mission as challenging and as painful as possible. This means you cannot timewarp the mission, there is no quick loading, no map, and ESPECIALLY, for some reason, NO GOING BACK TO THE MAIN MENU. Yeah, I'm just as surprised as you are that I'm even allowed to do that. The craft you see below is the craft you will be using to land on the Mün, which appears to have wasted fuel and oxidizer, so you basically only have 1/2 of it left, and 8 units of monopropellant. Sitting in a low orbit around the Mün, deorbiting is the easy part. It's the landing and not spiraling out of control that is the hard part. It's possible, but it's really hard. To install, download the scenario and put it in your scenarios folder that is located in the KSP saves folder. By default, for windows, this is located here(C:\Program Files (x86)\Steam\steamapps\common\Kerbal Space Program\saves\scenarios\). After that is done, you're good to go. You don't even need to reboot KSP!
  20. Sandwiches are mainly Meat, Lettuce, Tomato, Onion and Mayo. Tacos are mainly Meat, Lettuce, Tomato, Onion and Salsa. Are tacos a sandwich and are sandwiches a taco? Also, this post has gotten on the TOTM awards!
  21. I asked this on reddit and had some good feedback but I have one more day so I wanted to get any additional info. its been a year since I played at a buddies, my computer was a brick. My wife blessed me with a new computer I get tomorrow and I will be downloading ksp. The thing is I had a stroke last Father’s Day and I still haven’t regained movement in my right arm or hand. How hard would it be to play? Any suggestions? I’m getting a mouse with 6 buttons and I can use in my left hand. Any thoughts would be appreciated, thank you.
  22. Biggest Plane with a Juno! The challenge is simple: design an airplane powered only by a single Juno. Fly it from KSC to the Island airfield. Largest aircraft (by mass) on landing wins. Rules: Only stock parts FAR will have its own leaderboard. No other mods that affect physics allowed. No cheats The only propulsion allowed is the single Juno. No sepatrons, other engines, infiniglide, kraken drives, etc. Staging is fine, but your score is determined by the mass of your craft as landed A safe landing is not required, but any lost parts won't be included in your score Your craft need not be Kerballed No landing via parachute, although you may use parachutes to slow down once you're on the ground. To enter this challenge, please post a screenshot of your craft landed at the island airfield, with some sort of indication of mass (KER or MechJeb are helpful). For your efforts, you will earn the right to stick this little badge in your signature: A big shoutout to @doggonemess for putting together the badge! Stock Aero Leaderboard: Box of Stardust - 50,917kg hoioh - 41,179 kg neistridlar - 34,120 kg ManEatingApe - 31,760 kg GoSlash27 - 25,850 kg ZLM-Master - 25,616 kg Magzimum - 24,040 kg Numerlor - 22,113 kg Rocket In My Pocket - 21,173 kg zolotiyeruki - 20,340 kg doggonemess - 15,177 kg Andiron - 14,040 kg n.b.z. - 12,210 kg TeslaPenguin1 - 10,421 kg Gordon Fecyk - 9,973 kg Kerbal Design Bureau's interns - 7,460kg FAR Leaderboard: Here's proof for my entry:
  23. Yes you read it right 8139 parts, I just survived a lag hell with most of my sanity still intact... I think. Without the use of tweakscale I believe this is the biggest station ever created! (please correct me if i'm wrong) For quite a while I wanted to go big, really big so last week I finally went for it and build this space station. The pictures in orbit are of a incomplete version so they look a tiny bit different than the one in the SPH During this build I discoverd the true reason why there are ION engines in this game, and no not to provide thrust. They turn out to be cool lights! The interior It took 1.5 hours to load this thing on the runway, but it actually did load! Three frames later (1hour) I crashed the game in order to escape lag central. I would like to break the KerbalX record in part count but the filesize is to big to upload, almost 12mb lol
  24. So I thought I had posted a comment last night wherein I asked for advice re buying my son a suitable PC on which he can play KSP. He already plays it on his PS4 and maybe on his iPad as well or his netbook. The thing is, I don’t know if I successfully submitted my request for advice since I’ve yet to make my bold foray into the 20th century, let alone the 21st century. In other words, I don’t have a firm grasp on tech in general, and even less so when it comes to KSP. My son absolutely loves KSP and has been wanting to play it on PC for ages. He is 13 years old and of late has been experiencing occasional mild depression. I really want to buy him a PC and am excited at the prospect of being able to do so. But - and here’s where I call upon the KSP community - I have no idea what I should be purchasing. The only criterion is that KSP can be played on it. Please, please someone, anyone, any piece of advice or guidance would be so appreciated. I don’t know if it makes any difference but we live in Australia (Melbourne). And while I’ll be happy just to have enough knowledge to buy the right PC, you won’t see my name listed on the Forbes Top 50 Rich List, so it would be best to err on the side of cheaper, if that’s possible. Thank you sincerely (in anticipation) to whomever, if anyone, can help me sort this out. Ann (loving mother of a KSP devotee)
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