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Found 101 results

  1. As the title says : POST YOUR FAVOURITE SPACE RELATED IMAGES! Here are some that i like: (idk why it uploaded it with lower depth)
  2. [STOCK] SpaceX Family

    SpaceX family of Rockets A release thread for my SpaceX family of rockets Falcon 9 Falcon 9 Block 5 series of boosters with Various Cargoes. The booster is good for cargo up to a full orange tanks and can do geostationary launches with ease. The majority of the outer ring engines are at only 80% thrust and there is also space for more fuel. If you wish to re-land the booster separate the second stage at around 50km apoapsis, use a steep ascent, this will maximise your chances of returning to KSC, or head for island runway. Once separated activate the RCS and turn the booster and start burning retrograde. Once all the main fuel is gone hit action group one to deactivate all engines, bar the landing three, and enable the landing fuel. You can adjust your course with this fuel, but keep at least a quarter for the landing itself. Deploy the airbrakes to help slow down and keep the booster pointed retrograde. It will slow to just under 300ms without engines, after that it is up to you, I start boosting at about 1000m up and throttle back as I get closer. Falcon 9 with Dragon 2 Crew Capsule Dragon 2 and 'trunk' in orbit Falcon 9 with ComSat Cargo Falcon 9 with ComSat Cargo in flight Big Ears ComSat in orbit Falcon 9 and Orbital Construction Rig Orbital Construction Rig in orbit
  3. I was very busy for the past few months. Never got my dieselpunk SSTOs into orbit. My news feeds are now filled with SpaceX stuff after the Falcon Heavy launch, and now the successful fairing recovery test. Who knew, a great big rocket fairing could float like a leaf in the wind? Anyway, I asked for a joke commission about SpaceX and Tesla on Mars a few decades from now... and this arrived in my mailbox today:
  4. Trying to rotate spacex's Tesla in space

    Hey all. I did it again. Went to look at the "Starman" in his car. Drifting away from the Earth. And my right hand reached for the arrows on my keyboard and tried to rotate the car around so I could see the other side and a better view of the Earth. Too much KSP obviously. Anybody else care to admit to it? ME
  5. How not to land a SpaceX core

    Happen last night on my stream
  6. Dragon Analog

    Just something I needed:) A drogon V2 analog. Enjoy. Requires Firespitter. Added some stuff, spacedock seems to having issues at the moment so I'll upload there later on- Added 3.75 m parts Added attach node to inner part of the trunk trunk also hollow now Seems I managed to get it up on spacedock. Download there.
  7. KerbX, A direct product of SSSTS we will create the future of space! a new generation of rockets and an unlimited acsess to space About us: kerbX - users guide and history (more will be released closer too the launch of Falkerb X)
  8. A Mini SpaceX Falcon-9 Landing

    Here's another short video of my Mini Falcon-9 Landing on a barge like the real one. This is only for amusement, the video was reversed to look like a perfect landing. The craft is using one Juno Engine, I was hoping to get a small payload into Orbit but this may not happen on such a small scale. Hope you like it!
  9. Tribute: Tesla to Duna

    I created this challenge yesterday: And I just managed to complete it. I didn't score all the possible points, but I did successfully complete my main goal, which was propulsively landing all three booster cores within the same save. It's very challenging. The trick is to use a highly lofted initial burn, followed by a flat boostback on the first booster, an even-more-lofted boostback on the second booster, and a high-apogee downrange loft on the core. If timed properly, each booster can be landed before the following booster drops out. I suppose it doesn't look very Tesla-esque, but oh well. It can do about 50 mph, so we'll just chalk that up to it being a little on the old side. Corners ridiculously well, though, thanks to the low center of gravity. It survived this jump, surprisingly, though I believe it lost a headlight. Then came time to mate to the rocket! It's a big rocket. I could have made it smaller with Tweakscale, but didn't want to use mods. The Roadster takes its rightful place. The three cores are virtually identical, except for the fairings up top. Not shown: nine Vectors, thrust-limited to 92% (because Falcon Heavy will launch Elon's Tesla at 92% of its max thrust), with 100% gimbal on the core engine and 75% gimbal on the circle of engines. Time to head to the pad! Sitting pretty. Ignition before clamp release. Each of the 12 landing legs are an aligned pair of landing struts covered by elevons (with control authority turned off), keyed to the gear action group. "Check ignition "And may God's love be with you..." Starting a very, very mild turn at 100 m/s. Going to have a very lofted trajectory. At around Mach 1, I used an action group to cut thrust on all but the core's center engine. It's not perfect; the real Falcon Heavy will throttle all nine engines down to the minimum throttle together, but I couldn't be QUITE that perfect. Up, up, and away! I would have liked to use a reskin but oh well. Cutting all engine thrust to around 65% at 500 m/s to help loft the trajectory a bit more. Coming up on staging. The goal will be to separate and flip the first booster for boostback as soon as possible after apoapsis exceeds 70 km; that's when I know I'll be able to switch back and forth without problems. Am I correct that the navball automatically switches from Surface to Orbit as soon as your apogee exceeds 70 km? I suppose I'll have to test that another time. Anyway, it was the indicator I used. MECO and stage sep! Action groups are your friend. Leaving the core engine firing until I clear the two side boosters. I would have liked to have a single RCS thruster set to "fore by throttle" connected to a single monoprop tank, just to aid in separation, but there's no good way to do it. The core engine will fire until I am 2.5 km out of range, which should give me a bit of a loft. Using the engines to help with the flip on the first booster. The trick here is to get as flat a boostback as possible, but still keep my apoapse over 70 km so I'll be able to switch to the other booster in the brief window of time that I'm officially out of the atmosphere. All right, this boostback is almost done. Waiting to be able to switch back to the other booster... This one takes a much more lofted boostback burn, because I need a bit of hang time. I will only have a few seconds after I land the first booster before the second one would unload. Lofted boostback on the second booster, complete. Rapidly switched back to the core; I'd already crossed apoapse so I really have to gun these engines to get back onto a good trajectory. After getting my core to the desired trajectory, it was back to the first booster...with just seconds to spare. Already dropping like a rock. Used action groups to turn off the ring of outside engines but manually reactivated two of them for the three-engine burns to come. The first booster has a very gentle entry and doesn't need an entry burn. Landing burn starts pretty high, though. These engines are still limited to 92% thrust. I would have liked to come down closer to the beach, but I'll take what I can get. Booster is transonic. I'd toyed with using the airbrakes for control, but it never really worked right so I just made them fixed. Made sure to switch to radial-out at the right time; otherwise you end up going haywire at landing. Opening up those elevons and lowering the legs. Legs down; final approach. Throttling for landing. Dropping throttle lower. This will be a perfect hoverslam. And down! Still wobbly, but safe. And again, with seconds to spare, I switch to the next booster core. This time I'm already in re-entry while I'm switching my engines back on. Despite a higher-energy entry (given the more lofted boostback), I didn't need an entry burn on this one either. Starting the landing burn at roughly the same altitude; drag is the great equalizer here. Subsonic. Should have good fuel reserves. Still firing full-throttle. Legs down early this time...not really possible in real life, due to drag on the legs, but the drag from my airbrakes is so much higher than leg drag here that it doesn't matter. Less slam, more hover. I had enough fuel to counter gravity losses; my real concern was getting down fast enough to get back to the core before it hit the atmosphere. Made it! Couldn't resist a glamour shot with this core here and the other one in the distance. I really should have used Tweakscale to bump up the authority on the RCS thrusters, but I wanted to do it pure-stock. Uh oh; the core (and upper stage) have already dropped out of the atmosphere. This is going to be REALLY tight. Glad I didn't blow that fairing earlier. Boosting the upper stage free as soon as possible. I'm going to let the upper stage burn on its own while I switch back to the core. The engine will continue to fire until there is 2.5 km between the two vehicles; then the engine firing sequence is unloaded even though the vehicle persists on its trajectory. With luck, this will be just enough to get out of the atmosphere, but not so much that I waste all my fuel. Back to the core, switching to my three recovery engines. On this one, I'm DEFINITELY going to need an entry burn. (Spoiler: I tried without one, and most of the engines survive but all the airbrakes burn up.) "This is Ground Control to Major Tom "You've really made the grade" Thankfully it doesn't take a very long entry burn, though. Coming down in a mountainous region is going to be REALLY tricky. Deploying legs early to help me slow down, even though again this is NOT SpaceX kosher. Missed most of the landing burn, but here's the very last bit. A good deal of hovering and translation here to find a flat enough landing spot. Yikes! ....but I made it, didn't I. Now to see what happened to the upper stage! Hah! Still in the atmosphere, but with an exoatmospheric apoapsis. I'll go ahead and blow the fairing, though there's not much to see on the dark side. Should be a piece of cake from here on out. Getting ready to circularize. Stable orbit achieved! There she is! Roadster perched atop the upper stage. Now for the exit burn. POW. Five gees is a bit much for the real-life Tesla, but autostrut is our friend here. Pushing out of the system. And there we go! Hohmann transfer above Dunian orbit! Finally, the money shot. "Can you hear me, Major Tom? Can you hear me, Major Tom?" "Though I'm past one hundred thousand miles "I'm feeling very still "And I think my spaceship knows which way to go"
  10. Falcon Heavy to Duna

    With the Falcon Heavy's first test fire just days away, Elon's personal Tesla already mounted to the PAF, and the launch to Mars expected next month, what better time than Christmas break to build a Falcon Heavy in KSP and use it to send a battery-powered sports car to Duna? The Challenge: Build a battery-powered two-seat rover (with a probe core, please; this IS a Tesla we're talking about), mount it on the single-engine upper stage of a three-stick parallel-staged launch vehicle, and send it to a Duna-intersecting orbit! Recover as many components of your launch vehicle as possible. All mods are allowed, but try to keep it as close to stock as you can, and name whatever mods you use. Scoring is based on accumulation of points as follows: Gone For a Spin (10 points): Before the launch, demonstrate your Roadster's moves by driving it around the KSC. Speed Demon (15 points): Test your Roadster at speeds over 100 mph (45 m/s). Falcon Nine (27 points): Use nine engines on each of your booster cores. Autonomic (13 points): Use drone cores; nothing manned. Looking Easy (16 points): Recover at least one parallel booster. Insane Mode (42 points): Recover both parallel boosters with boostback, RTLS (anywhere on KSC continent), and propulsive landing. Downrange (19 points): Recover your center core. Supercruise (18 points): Recover your center core by landing on a boat. Tru Lyfe (33 points): All booster recoveries without chutes. Hail Mary (28 points): Bring back the upper stage. Double Trouble (26 points): Build your own fairings and recover at least one. Purity (30 points): No mods. Destination (22 points): Land your Roadster on Duna and take it for a spin! Leaderboard: @Ultimate Steve: 277 points @LightBender: 196 points @sevenperforce: 190 points
  11. Thank you KSP

    Just a fun little post here thanking the game and community for the added enjoyment of last night’s space x launch. I got a phone call from my fiancé asking if I saw the weird plane in the sky. I turned to look and was struck with awe and fear as I saw a massive light with an even bigger tail. My brain quickly raced through the possibilities of what it could be. Was it a returning space shuttle? No, NASA hasn’t launched a shuttle in years. A meteor? No, we would have heard of it’s approach. Oh god could it be a missile? My fears grew as I saw something detach from the craft. “Oh no, it’s a warhead” I thought. Then after that 10 seconds of confusion and fear, my 500+ hours of KSP experience kicked in. It was a rocket!!! I quickly ran through what I was seeing: The contrail due to it reaching the colder upper atmosphere, the gap in the contrail due to throttle down, the throttle up once it had gained enough altitude to not have atmospheric resistance, the separation of the main stage, the ignition of the secondary engine, and the spinning of the main stage in space and it’s eventual reentry into earths atmosphere. I called my friends and family, most of whom were scared it was a UFO or missile themselves, and explained to them exactly what was going on, all thanks to an indie video game. Since then I have been obsessed with watching footage on social media, the space X stream of the launch (link below) and KSP videos. It was truly an awesome thing to see but even more awesome to scientifically understand what I was seeing. To be able to break down each step in the process but also to understand why it was happening. Thanks to this game a cool experience turned into an amazing one. Thank you Kerbal Space Program for being such a great game that I was able to take experience from a game and turn it into understanding of an actual rocket launch. This is my favorite game I have ever played and now, thanks to Space x, I love it even more. See you in the skies!
  12. I was intrigued with Elon Musk's tweet about launching his Tesla Roadster to the "orbit of mars". I had RSS setup in KSP and decided to simulate such a launch using Shadowmage's SSTU mod to make a Falcon Heavy and a demo payload. I proved to myself that such a mission was possible. I made a video of the result using camera tools: Falcon Heavy Demo Mission Simulation in KSP. Can't wait for the real life launch!
  13. Hello everyone! Today, we'll be making a new mod! And this time, I actually will make this mod, instead of immediately abandoning when I finish. This mod will feature SpaceX Grasshopper parts and in the future, other SpaceX parts. No non-SpaceX related parts here, unless people really want it. Huge credits to @SamBelanger for helping me make this mod (in the future): Download: Coming soon.
  14. Falcon Heavy in RSS

    Not the practical mission but the artistic one. It does work but this video just shows it off and has the boosters landing close together. In reality they don't. I used smurf and upgraded vector engines to SSME details.
  15. Hi there! After a ton of work (5 months) because I didn't wanna look up a tutorial, I was able to powered land a Reusable Rocket, known as Ender Full Thrust (Ill upload the craft file, however it uses a lot of mods, so it might not work for you, MRS and Kerbal Reusability Expansion should be it, but I might have some other mods in it to.) So here is the mission report I lifted of from KSC, and because the thing sometimes tips in water, I headed to polar orbit. I deployed the satellite at around 40 KM, and flew it into orbit. I then had to switch back to the rocket, as it entered the atmosphere. I fired up 1 of the 5 engines, and slowed down. I only used 1 as it was honestly just more efficient. I ended up deploying the gear at around 5km, as the extra drag kept the thing from tipping over. I fired up all the engines, slowed down, and just about managed to land it. I probably hit ground at around 3-5 m/s, so I was lucky that the landing gear had some good suspension. I actually nearly tipped the thing, however the RCS fought back, and it ended up stable. And that's the mission report of the first ever successful flight of Ender Full Thrust.
  16. Falcon Heavy Replica

    This is my first post, and with the upcoming December Falcon Heavy launch, I decided to share the SpaceX Falcon Heavy replica I made. I couldn't get an image here, but here's the download: Falcon Heavy Download A few mods are required for it to work though: -Kerbal Reusability -Kerbal Engineer Redux -FMRS If anyone else wants to take a screenshot and upload it, that would be appreciated. Thanks!
  17. This mod was originally created by @tygoo7 (here) and will be continued by me. Tundra Exploration will continue to focus on stock-alike SpaceX and various other space related parts in KSP. Expect many more parts to be added in the future. If you have any suggestions, please leave a comment Beta versions on GitHub Current parts Rodan command pod, heatshield, and trunk. It also has a nice IVA included. (Dragon V2) Staub control block, fuel tank, and OCS. (LADEE) Ghidorah 9 fuel tanks, second stage engine, first stage engine, legs, grid fins, and decoupler (Falcon 9) Gigan pod, heatshield, shroud, trunk, solar panel, solar shroud. (Cargo Dragon) Igel probe (Hedgehog probe) Paneer probe (New Horizons) Moguera probe (Rosetta) Pill probe (Philae) Gojira command pod with fuel tank, engine shroud and engines (SpaceX's BFS) Gojira BFT-9000 Fuel Tank, engines and probe core (SpaceX's BFR) Revamp Ghidorah 9 textures (includes a brand new version as well as a landed/reused one) (Needs B9 Part Switch) Mothra Launcher (Falcon 1) No IVA on Gojira, but coming in future update Planned features Roadmap Known issues Landing Gojira might be hard. A guide is being made to teach you how to use Gojira. Caution using Gojira for stations, it can wobble and break it. Use "Autostruts" on Gojira for a temporary fix! Some mismatch with the fuel tanks on Mothra. Cargo Gojira's textures are weird (I haven't redone the model yet) Required Mods Kerbal Reusability Expansion (F9 and BFR legs and gridfins) B9 Part Switch (Texture switch comes in V2.1.0, get that!) Near Future Solar (Full version for BFS solar panels) Recommended Mods RealPlume Stock Configs Flight Manager for Reusable Stages (For landing your BFR/F9 first stage) Omega482's Stockalike SpaceX style landing pad (For your Ghidorah and Gojira landing needs) Basic DeltaV - Basic Orbit by DMagic (For better understanding of how much fuel you have to land all your crafts safely back) by @macktruck6666 A very special thanks to @Beale, @CobaltWolf and @Nertea for the help and advise they give me to make something awesome. @Rock3tman_ for helping balancing the BFR parts as well as testing! And @DiscoSlelge for creating those awesome patches! Changelog: Any Code or configs are distributed under CC-NC-SA-4.0 License. All Textures/models are distributed under All Rights Reserved License. This mod includes version checking using Mini-AVC. If you opt-in, it will use the internet to check whether there is a new version available. Data is only read from the internet and no personal information is sent. For a more comprehensive version checking experience, please download the KSP-AVC Plugin.
  18. The full post for you to enjoy and discuss, from here: Performance estimates revised: 24 tons expendable, 12-14 tons recoverable to LEO. The Small Falcon Rocket is a scaled down alternative to SpaceX's Big Falcon Spaceship that fits on top of existing Falcon 9 boosters. We will discuss the advantages and disadvantages of such a design. SpaceX's Big Rockets The BFR, or Big Falcon Rocket, is comprised of the Big Falcon Spaceship and the Big Falcon Rocket booster. It is a scaled down and simplified design based on the ITS, or Interplanetary Transport System. The BFR is a BIG rocket. The ITS was revealed in June 2016, although work on the design has begun in 2013 under the name 'Mars Colonial Transporter'. The ITS promised to deliver 300 tons of cargo to Low Earth Orbit, or up to 550 tons if reusability was ignored. It would have massed 10500 tons on the launchpad. The vehicle had a diameter of 12 meters and a height of 122 meters, making it one of the largest rockets ever plausibly considered. And the ITS was positively massive. The upper stage, called the Interplanetary Spaceship, was supposed to hold 1950 tons of propellant with a dry mass of 150 tons. Without a payload, the mass ratio was 14. The BFR replaced the ITS in September 2017. It is a smaller, more sensible design that SpaceX believes it can actually deliver in the next few years. The diameter is reduced to 9 meters and it will mass 4400 tons on the launchpad. Payload capacity is reduced to 150 tons. The upper stage BFS should have a dry mass of 75 tons, but Elon Musk states that this might rise to 85 tons due to development bloat and overruns. It holds 1100 tons of propellant, giving it a mass ratio of 13.9. It is important to note that despite being up to 78% smaller than the previous ITS design, the BFS stage maintains the same mass ratio. Why? Because we are now going to scale down the BFS again. Why go smaller? How big the BFR's booster would be compared to the Falcon 9 booster. Going big is the best way to reduce the cost per kilogram for sending payloads into orbit. SpaceX jumped from the Falcon 1 to the Falcon 9 because the larger rocket can deliver payloads much more cheaply into space. When first considering options on how to make travel to Mars affordable to the general population, SpaceX immediately came up with a gargantuan tower of rocket fuel over three and a half times larger than the Saturn V! A big rocket is also easier to develop. It is more forgiving of development bloat that increases mass over time as the designs are perfected. It has larger safety margins and room for many backups, such as multiple engines. However, bigger is not always better. The total development costs will be higher, as large components need large factories. It is much more difficult to test the components too, and a full testing regime of the completed rocket will require launching and even destroying a full-scale model many times. Remember the failed Falcon 9 booster landing attempts, and imagine them replaced with a vehicle eight times bigger. There is also the fact that the second sure-fire way to reducing launch costs is to have rapid turnover. This involves loading up rockets, sending payloads into space, recovering the rocket and refurbishing it for another launch in a very small time frame, measured in days or even hours. Rapid turnover and minimal refurbishment would allow the space launch industry to more closely resemble existing airline business models. The main benefit of this approach is that a small number of launch vehicles can handle a large volume of missions, critically reducing the initial cost of the vehicles and reducing the amortization rate. Even if SpaceX manages to develop rockets that liftoff and land several times without needing to go to a workshop, they'd still need to solve the issue that there just aren't enough payloads on the market that need to be lifted into space to fill the BFR, let alone the ITS. For example, even the BFR's 150 ton payload capacity can cover all of last year's payloads in about two or three launches. Three launches is far from sufficient. Elon Musk is betting that the space industry will be able to fill the BFR's cargo bays with new satellites and LEO payloads once the lowered cost per kg is offered to them... but there will be a long delay between the launch costs being reduced and the industry contracts appearing en masse. Cost per kg in orbit is only part of the picture. Waiting for more contracts to appear and bundling them together to use the most of a BFR's cargo capacity is not a good solution. It will force SpaceX to delay launches until the mass delivered to orbit reaches a profitable amount - launching BFRs nearly empty with the usual 2 to 5 ton satellite is surely wasteful and a loss for the company. The SFR The SFR, or Small Falcon Rocket, is a possible solution to the development costs, under-utilization and low expected launch rate of the BFR, or Big Falcon Rocket. The SFR is a scaled down Big Falcon Spaceship sitting on top of an existing Falcon 9 booster. It will carry a smaller payload to orbit, but will have a capacity SpaceX is sure to fill up. Existing Falcon 9 boosters can be mated to a fully reusable upper stage, drastically cutting down on development costs. We will now look at the details of the SFR's two stages. The upper stage is the only new part. It is a BFS scaled down to 3.7 meters diameter, using the same Raptor engines rated at 1900kN of thrust at 375 seconds of Isp. We will call it the SFS, or Small Falcon Spaceship. The Raptor engine. The SFS will be (9/3.7)^2: 5.9 times smaller than the BFS. The dry mass is expected to be only 85/5.9: 14.4 tons. It will be 19.7 meters long. Based on the mass ratios calculated above, the SFS will be able to hold 187.2 tons of propellant. An SFS with no cargo and full propellant tanks will therefore mass 201.6 tons and have a deltaV of ln(14)*375*9.81: 9708m/s. The Vacuum-optimized Raptor engine is quite large, with a nozzle opening 2.4 meters wide. It is unlikely that more than one such engine can be fitted under the SFS. It will provide enough thrust for an initial Thrust-to-Weight ratio of 0.96, which must be compared to the current second-stage initial TWRs of 0.8-0.9. For retro-propulsive landing, we will not be able to fit, or even need, the sea-level version of the Raptors. Instead, we will use two of the existing Merlin-1D engines with 420kN of sea-level thrust, but possibly with a lower pressure rating as the thrust generated makes them too powerful for landing. The alternative is the SuperDraco engines with 67kN of thrust and 235s sea-level Isp. Rocket engines in the Raptor + 2x Merlin configuration would represent 13.2% of the overall dry mass, or 8.1% if the Raptor + 4x SuperDraco configuration is used instead. The Raptor engines are assumed to have a TWR of over 200, so their mass should be lower than 969kg. There are no numbers on the SuperDraco's mass, but it should be at most 50kg. These ratios seem not too outrageous when compared to the 7% engine-mass-to-dry-mass ratio in the BFR's original design. Merlin-1D engines. The SFS's mass is based on the 85 ton figure for the BFR's dry mass, but this is a cautious estimate with room given for development bloat and mass budget overruns. The BFR's design on paper gives a dry mass of 75 tons instead. Using the on-paper mass, the SFS could have a dry mass as little as 12.7 tons. The SFR's booster is the Falcon 9 Block 4. The booster will mass 22.2 tons when empty, and can hold 410.9 tons of propellant. This gives it a mass ratio of 19.5. The nine Merlin 1D engines have a sea-level Isp of 282s and an vacuum Isp of 311s. Because the booster stage does not spend a long time at sea level and performs most of the burn at high altitudes with negligible air pressure, we will use 300s as a low-ball estimate of the average Isp. The true average might be a few seconds higher. Taken all together, the SFR will mass 634.7 tons on the launchpad without any payload in the SFS's cargo bays. It stands 89.7 meters tall. We will now calculate how much cargo it can lift into Low Earth Orbit in expendable or reusable mode, and where else it can go. Performance To achieve a Low Earth Orbit, we will set the deltaV requirement as 9400m/s. In reality, it could be achieved with as little as 9200m/s, but we want decent safety margins. Expendable mode is the easy part. It assumes every bit of propellant is consumed and the SFR's stages left dry. Using a multi-stage deltaV calculator and setting the Falcon 9 Block 4's Isp to 300s and the SFS's Isp to 375s, we work out that the booster provides 1899m/s of deltaV and the SFS provides 7488m/s for a total of 9388m/s with a payload of 13.7 tons. Recoverable mode is harder to calculate. The propellants cannot be completely used up: some must be kept in reserve to perform a retro-propulsive landing burn. BFR landing. A landing burn by the SFS requires that about 300m/s of deltaV be held in reserve. This represents 1.65 tons of propellant with Merlin-1Ds or 2 tons of propellant with the SuperDracos. The Falcon 9 booster needs to retain 15% of its propellant reserve to make an ocean landing. This gives it a deltaV of 3910m/s, which is largely enough to cancel most of its forwards velocity and make a very soft landing. However, holding back 61.6 tons of propellant means it boosts the SFS by much less. In recoverable mode, the SFR's cargo capacity drops to 9 tons. If the SFS follows the paper designs more closely and achieves a dry mass of 12.7 tons, it will have cargo capacities of 16.7 tons in expendable mode and 12 tons in recoverable mode. The SFS could achieve a deltaV of 2500m/s after launching on top of a recoverable Falcon 9 booster and without any payload. This is not enough to reach the Moon, so the range of missions the SFR can take payloads on is limited to Low Earth Orbit. Smaller rockets might solve the problem of having to crane down cargo from the top of a tower. However, if it is refuelled in orbit, then the entire Solar System is available. It can deliver 50 tons to Low Lunar Orbit (5km/s mission deltaV). It can send 35 tons to the Mars Low Orbit (5.7km/s mission deltaV) or 21 tons to Mars's surface (6.7km/s mission deltaV). Refueling the SFS will take between 16 and 20 tanker launches. With 14.4 tons of dry mass and a propellant capacity of 187.2 tons, the SFS has a maximal deltaV of 9.7km/s, enough theoretically to put itself far above Jupiter or even Saturn. Conclusions The SFS is a limited vehicle. It is restricted to Low Earth Orbits and can deliver payloads of 9 tons, up to 12 tons, at most. It is far from the multi-purpose machines the BFR or ITS promised to be. However, it is enough to dominate the medium lift launch market, as it is fully recoverable. The re-use of existing Falcon 9 boosters and the smaller number of Raptor engines (one per rocket) will drastically slash the development costs compared to something like the BFR. The smaller payloads are easy to fill, meaning every launch is profitable. Multiple launches promises rapid turnover and a maximization of the return on investment on the craft. With re-fueling, the SFS in orbit can complete missions that require it to send decent payloads to the Moon and Mars. With minor improvements and operating in fleets of multiple vehicles, it can even match the payload capacity of the BFR to various destinations. What do you think?
  19. Shocked no one has done this yet...but glad, because I wanted to be the one to do it. I'm sure most of us have seen Elon Musk's 2017 IAC presentation, which raises the bar (even though that "bar" is somewhat smaller) tremendously over the 2016 version of BFR/ITS/MCT. If anyone hasn't had a chance to see it, I highly recommend checking it out: What's the challenge? Build the 2017 version of the BFR, of course. Specifically: Build a large two-stage fully-reusable launch system capable of propulsive landings on Duna, Kerbin, and the Mun. It must be capable of in-orbit propellant transfer and needs to be able to deliver substantial payload (at least 20 kerbals, or a fully-functioning autonomous ISRU unit) to Duna. No nukes, ions, jets, rolling landings, or parachutes. Tweakscale is the only allowed part mod for engines and tanks. Once you've demonstrated proof of concept with a single launch, subsequent launches (for refueling, etc.) may use the debug menu to get into orbit. You can also use Unbreakable Joints and No Crash Damage as long as your landings are under 5 m/s. The scoring system is designed so that the closer you make your version to the one revealed by Musk, the more points you get. I may add additional ways of earning points as the challenge progresses, but I'll try to keep it balanced. Scoring: Basic challenge (two-stage, reusable, propulsive landings on Duna, Kerbin, and the Mun): 5,000 points Booster executes RTLS: 200 points Dedicated propellant transfer ports in tail: 50 points Single-stage to Mun and back to Kerbin after Kerbin orbit refueling: 600 points Demonstrate single-stage return from Duna to Kerbin after Duna ISRU: 800 points Six engines on second stage: 60 points Thirty-one engines on first stage: 31 points No reaction wheels: 200 points No monoprop (Vernor engine RCS only): 175 points Booster lands in launch cradle: 650 points Delta wings on second stage: 85 points Dedicated crew vehicle, cargo vehicle, tanker: 400 points Ties are broken by total upper stage dry mass, the lighter, the better.
  20. Taking a break from all my spaceplanes, I'm trying my hand at making a stock, recoverable two stage rocket. The booster stage has wings and will glide back to the space centre, before landing on parachutes. The upper stage also has stub wings (mainly to help it aim and slow down) and parachutes. The goal is to come up with something you can put on KerbalX and have the average joe just be able to fly it, without having to install mods or tweak physics range etc. As you can imagine, physics range is the bugbear. I keep finding one or other part of my rocket has gotten auto deleted before I can deal with the other. Each time i want to tweak separation altitude/ascent profile, means a complete redesign, moving propellant from one stage to the other then having to rebalance the aerodynamics so each component is stable on its own. If you guys can help with that, it will save a lot of time building iterations of this rocket. Attempt 1 My first iteration only had about 1000dv on the lower stage, but with 8 aerospikes the lower stage was pretty powerful (TWR 2.75) and launched steeply. Separation altitude was 20km and due to the steep ascent, the first stage didn't have a long glide to get back to the space centre. The upper stage had about 1900dv but only 0.5twr and i think i should have boosted that, in retrospect. The problem is, these engines only run for as long as i'm flying that vessel. They do take the upper stage's AP out of the atmosphere, but as i understand it, I have to switch back to the lower stage before it gets more than 2.5km away. EDIT - ok, it appears the non-focused stage is ok so long as it stays above 25km OR is within 2.5km of the flown vessel. When i switch to the lower stage, the upper stage's engines immediately stop and it is still well below orbital velocity. It completes the sub-orbital arc and falls below 25km and gets deleted before i can land the lower stage. Attempt 2 I tried adding extra fuel to lower stage and removing from upper. The lower stage now has 1700dv. Separation was at 950m/s at 35km in a 65 degree climb. The booster reached 65km before falling back. I still wasn't able to put enough velocity on the upper stage before having to switch back to the booster, and it fell back below 25km again just as the booster was opening its parachutes. I don't like adding more fuel to the booster, it means either a very inefficient lofted trajectory or being too far from the space centre to glide back at separation. So, it seems i need to give the upper stage some serious TWR so it can get close to orbital velocity much quicker. BTW, what happens if the upper stage is an SRB? Does that magically extinguish itself when i switch away from the vessel ? Just thinking out loud.
  21. Elon/SpaceX is amazing

    Can we talk about how amazing this is, and how Elon is single handedly going to push humanity into a new era?
  22. You could have made the same argument about any colonization or exploration people have ever made in the past. And it would be wrong in almost every case.
  23. Does anyone have tips on how to land 2 seperate boosters decoupled at the sametime in the lower atmosphere?