MisterKerman Posted July 18, 2018 Share Posted July 18, 2018 55 minutes ago, Triop said: What do you mean with flight profile ? What Mephisto gave me. Quote Link to comment Share on other sites More sharing options...
Triop Posted July 18, 2018 Share Posted July 18, 2018 5 minutes ago, MisterKerman said: What Mephisto gave me. Who's Mephisto ? No idea what you are talking about. Quote Link to comment Share on other sites More sharing options...
Mephisto81 Posted July 18, 2018 Share Posted July 18, 2018 Life goal achieved. People are confused. Quote Link to comment Share on other sites More sharing options...
MisterKerman Posted July 18, 2018 Share Posted July 18, 2018 Ikr. Quote Link to comment Share on other sites More sharing options...
Triop Posted July 18, 2018 Share Posted July 18, 2018 Just now, Mephisto81 said: Life goal achieved. People are confused. I'm speechless right now... Quote Link to comment Share on other sites More sharing options...
MisterKerman Posted July 18, 2018 Share Posted July 18, 2018 Btw Mephisto that's a great looking SSTO and your flight profile gave me some guidelines for my own if I try one that size. I'm in no position to be designing payload capable SSTOs yet. Basically if you can make it to 1500m/s at 20k for a rocket burn, you're good? Quote Link to comment Share on other sites More sharing options...
Mephisto81 Posted July 18, 2018 Share Posted July 18, 2018 And now, for something productive: Anuki Kerman is LOST IN SPACE. Naturally, Bill decided to design a brand new SPACEPLANE for the daring rescue mission. With clever book keeping tricks, Bill managed to get proper funding for the craft. Because space is big and scary, Bill decided to play it safe: 10 Rapiers, 3 Skiffs and 4 Nerv Engine would propel the 200 t craft. Just in case, the craft was build with a modest error margin: The craft was able to reach the outer planets or Moho and refuel with its ISRU. One can never know. 7000 m/s maximum range with only liquid fuel tanks should be enough. As the craft is quite overpowered, Bill was pondering, whether he should also include an Eve Lander at the front? Mini Tylo Lander in the cargo bay for later? And notice the fairing right behind the cockpit. In a later version, I might add an Eve Lander onto the front and build a fairing around it. A small cubic octogonal strut right behind the shielded docking port allows for part attachment to a shielded docking port. Normally, they lack attachment nodes. Will the craft suffice for a rescue from low Kerbin orbit? We will see... Mephisto (Insert witty one-liner here.) 2 minutes ago, MisterKerman said: Btw Mephisto that's a great looking SSTO and your flight profile gave me some guidelines for my own if I try one that size. I'm in no position to be designing payload capable SSTOs yet. Basically if you can make it to 1500m/s at 20k for a rocket burn, you're good? Airbreathing engines are much more fuel efficient than rocket engines. (Efficiency is often measured as Isp, the higher, the better) Therefore, every m/s you can get out of your airbreathing engines saves you oxidiser. Oftentimes, I fly quite lazy and only reach 1450-1500 m/s at that height. Rest has to be done by Rocket Engines until orbital speed of app. 2240 m/s is reached (from the back of my head) But most vacuum-optimised engines like terriers or Nervs, even Ion Engines, bring almost their full thrust there as well. So, if you have a spaceplane with rapiers and Nervs, you can switch on the Nervs when the rapiers are still breathing air at 18km. Quote Link to comment Share on other sites More sharing options...
MisterKerman Posted July 18, 2018 Share Posted July 18, 2018 5 minutes ago, Mephisto81 said: Airbreathing engines are much more fuel efficient than rocket engines. (Efficiency is often measured as Isp, the higher, the better) Therefore, every m/s you can get out of your airbreathing engines saves you oxidiser. Oftentimes, I fly quite lazy and only reach 1450-1500 m/s at that height. Rest has to be done by Rocket Engines until orbital speed of app. 2240 m/s is reached (from the back of my head) But most vacuum-optimised engines like terriers or Nervs, even Ion Engines, bring almost their full thrust there as well. So, if you have a spaceplane with rapiers and Nervs, you can switch on the Nervs when the rapiers are still breathing air at 18km. Oh okay cool. I've made SSTO's on previous versions but I'm rusty right now and ill equipped tech-wise. I've never yet brung anything meaningful to space in an SSTO though, only dumb kerbals. I just wanted a flight profile for a very small personnel shuttle to avoid a little of the trial and error when I'm ready to start building them again. Thanks! I'll stop littering discussion in this sharing thread though. I've mucked things up enough! Quote Link to comment Share on other sites More sharing options...
Rune Posted July 18, 2018 Share Posted July 18, 2018 (edited) 14 hours ago, Mephisto81 said: Mephisto (Insert witty one-liner here.) That bit seriously cracked me up. Also, cool SSTO! 14 hours ago, MisterKerman said: Oh okay cool. I've made SSTO's on previous versions but I'm rusty right now and ill equipped tech-wise. I've never yet brung anything meaningful to space in an SSTO though, only dumb kerbals. I just wanted a flight profile for a very small personnel shuttle to avoid a little of the trial and error when I'm ready to start building them again. Thanks! I'll stop littering discussion in this sharing thread though. I've mucked things up enough! Ever since the souposphere went away, SSTOs have much simpler 'flight profiles'. The one I use, which is a good compromise between efficiency and expediency, is quite simple indeed: draw a straight line to orbit. Basically, put yourself on the shallowest attack angle that doesn't make you go down right from takeoff... and then do nothing. As you build speed and go supersonic, waking up the RAPIERs, you build TWR and lift, and you start ascending, quicker and quicker, until you get to ~1300m/s @20,000m with a more than respectable vertical component (Kerbin has curved under you as you kept the initial heading). You could milk a bit more by pitching down, but I usually just don't bother. Also, this profile is very dependant on TWR, I get my best payload fractions (up to 50%) at around 0.4 TWR, with an all-RAPIER powerplant. That last number is probably the second most important thing in designing a SSTO... the first is to minimize drag (no open nodes anywhere!). Rune. Asking for advice politely is rarely out of place, anywhere. Edited July 19, 2018 by Rune Quote Link to comment Share on other sites More sharing options...
MisterKerman Posted July 19, 2018 Share Posted July 19, 2018 You guys. <3 Quote Link to comment Share on other sites More sharing options...
katateochi Posted July 19, 2018 Share Posted July 19, 2018 2 hours ago, Rune said: The one I use, which is a good copromise between efficiency and expediency, is quite simple indeed: draw a straight line to orbit That's similar(ish) to what I've been doing; I take off and pitch to 10 degrees and just floor it. Once the speed reaches 1000-1500m/s I pitch up to 15 degrees. On the overpowered SSTOs that's more to stop the front overheating than anything else. On the ones with low TWR rocket engines I found that giving a boost to the vertical speed and bumping the Ap up more while still air-breathing helps. 2 hours ago, Rune said: the first is to minimize drag (no open nodes anywhere!). the truth. Quote Link to comment Share on other sites More sharing options...
Mephisto81 Posted July 19, 2018 Share Posted July 19, 2018 (edited) That is an interesting flight profile. Straight line is rather simple, if TWR is sufficient. 0.40 TWR sounds quite sufficient to me. And I second the part about drag. "Drag is king" I had crafts, which flew good and accelerated beyond the 400 m/s mark, but then a tiny bit changed and suddenly there was too much drag. This craft here is a good example, still scheduled for release in the next couple of days: This is a study, whether I can bring three Kerbals with a full science suite to almost anywhere in a lightweight plane. SSTA light, if you allow me to call it, powered by one rapier and one Nerv. Apart from getting the torque offset reduced by the Rapier and the Nerv, similar to some crafts from Turbo Pumped and Stratzenblitz, getting the drag down was an issue. Especially the service bays produced different amount of insane drag. Then, I realised that the drone core had to be put in front of the service bays, so that his slightly larger diameter can shield the bays behind from drag. Rearranged the order of service bays, drone core and science junior and ... the craft flew past 400 m/s again. No additional mass or parts, just rearranged the order. Another example of SSTO design margins is this one here, my beloved XR-02 Ranger. Inspired by the XR-2 Ravenstar from the Orbiter Space Flight Sim and the Ranger from Interstellar, it is one of my most efficient builts. This brick can land on Tylo and take off again whithout the need for a seperate lander, fly to the fiery depths of Moho. Only for Eve, I need an dedicated lander. As you can see, the take-off weight is around 89 tons, powered in atmosphere by only three Rapiers. This comes very close to my goal of 30 tons per rapier engine. The reason was to save engine weight, as Rapiers are mostly dead weight in space. For the weight of one rapier I can add two Skiffs, giving me much more rocket thrust and a higher efficiency (Rapiers have an Isp of 305 seconds, Skiffs of 330 seconds in vacuum). But now my TWR in atmospheric flight is only 0.36, which is a good part below 0.4. I had to really optimize the craft. The wings are slightly angled upwards, so the craft's body is more alligned with the airflow. This reduces drag. "Lift with the wings, not the body" All the open nodes on the outside are covered, no parts are sticking out. The different parts have been carefully checked in flight for drag. "Open nodes are draggy" Fun thing was, the frontal fuel tank, the 2.5m to Mk2, which I wanted for the looks, was producing insane amount of drag. Apparently, the fairing didn't register properly with it. Solution was to put a adapter plate right behind it. Suddenly, frontal drag was much more managable. The ascent profile depends on the Rapiers getting beyond 400 m/s at sea level, as the air is thickest and the thrust from the rapiers is the highest. After I got some speed, I can start to climb. With this low TWR, a straight line to orbit is not manageable for me. The rest of the way to space was easy. Mephisto (Attention span of a squirrel. Oh look, an SSTO!) Edited July 19, 2018 by Mephisto81 Am I the only one who notices spelling mistakes directly after publishing a post? Quote Link to comment Share on other sites More sharing options...
Rune Posted July 20, 2018 Share Posted July 20, 2018 (edited) I feel almost obliged to say, though, SSTA are notoriously simpler to design if you forget about efficient airbreathers. I mean, I managed to do it using Mk3 fuel tanks and their lower mass fractions (I wanted the aerobraking option with high heat tolerance). Heck, I even put on wings, mostly for looks but also useful for precise landings. And of course, if you can single-stage Kerbin, you automatically can single-stage Tylo with TWR to spare. Rune. The flight profile is also quite simpler. Edited July 20, 2018 by Rune Quote Link to comment Share on other sites More sharing options...
Rune Posted July 20, 2018 Share Posted July 20, 2018 (edited) Oh, and while we are at it, let's post something more recent than 'a couple game versions ago'. The latest SSTO in the arsenal, the Altair, a very proper rocketship: 5mT to orbit in a spacious cargo bay. Good enough to set up a Base Pack and serve as shuttle on Tylo, reusably, without having an incredibly high fuel resupply issue (~90mT wet weight). Plus, it can also do daring aerobrakes on, say, Laythe. Oh, and did I mention it can land-dock to my surface bases without use of the Klaw? Cause yeah, it does. Rune. Coming 'whenever I get around to posting it™'. Edited July 20, 2018 by Rune Quote Link to comment Share on other sites More sharing options...
Mephisto81 Posted July 20, 2018 Share Posted July 20, 2018 Your Altair is a really sexy craft. Did you choose Aerospikes for aesthetics? And did you have any issues with exploding landing gear, if I may ask? Quote Link to comment Share on other sites More sharing options...
Rune Posted July 20, 2018 Share Posted July 20, 2018 59 minutes ago, Mephisto81 said: Your Altair is a really sexy craft. Did you choose Aerospikes for aesthetics? And did you have any issues with exploding landing gear, if I may ask? Oh, the landing gear bug. Yes, quite horrible. Quicksaving before undocking anthing is a must, these days. As to the aerospikes, their high Isp, especially sea-level Isp, allowed me to get by with a pretty crappy tankage fraction (the only efficient tanks I use are behind a fairing). So in spite of their low TWR, which is a big downside, I end up needing slightly less juice to refill the tanks in orbit. There is also the flip side that the lowest temp. rating of any exposed part is 2,300° (with the weird exception of the engines). And the fun engineering problem of providing six axises of RCS control, since I used no reaction wheels. But yeah, aesthetics was 90% of the real reason. Rune. The rest are engineering excuses to justify the choice. Quote Link to comment Share on other sites More sharing options...
Korsakovski Posted July 25, 2018 Share Posted July 25, 2018 Ended up making another remake of a remake. (Again.) Asgard ALX Slightly less cargo capacity than the original, but has two mk3 passenger cabins. https://imgur.com/a/C4w9Wdf https://kerbalx.com/Korsakovski/Asgard-ALX Quote Link to comment Share on other sites More sharing options...
Hodo Posted July 29, 2018 Share Posted July 29, 2018 (edited) Been gone awhile but still working on new things... It is a tail landing, vertical take off SSTO. Completely rocket powered, no jets. Over 4k Delta V, on take off. Good solid launcher... landings are tricky but hey what isnt. Edited July 29, 2018 by Hodo Quote Link to comment Share on other sites More sharing options...
Mephisto81 Posted July 31, 2018 Share Posted July 31, 2018 Hm, have not built Vertical SSTOs yet. Apart from some reusable Tylo landers, who can make orbit on Kerbin as well. Could be an interesting topic. How much payload does it have to LKO? And this is for FAR? Quote Link to comment Share on other sites More sharing options...
Mephisto81 Posted August 2, 2018 Share Posted August 2, 2018 Grand Tour Vessel, XR-06 Ranger Mk III with Javelin Eve Lander Landed at Laythe. Landing earlier on Gilly for refueling and dropping the Javelin Eve Lander to ... Eve. Put it finally up on Kerbalx. Grand Tour is almost finished, only have to finally land on Kerbin at the KSC. I have the highest respect of anyone who can pull a Grand Tour of without Mechjeb and doing Gravity assists and other fancy stuff. I had a rather brute force approach to interplanetary transfers... KerbalX Link: XR-06 Ranger Mk III "Grand Tour" SSTA with Javelin Eve Lander and Ascent vehicle https://kerbalx.com/Mephisto/XR-06-Ranger-Mk-III-Grand-Tour-with-Javelin-Eve-Lander XR-06 Javelin Eve Lander and Ascent vehicle (without Ranger or a fairing. the naked version, if you want it so.) https://kerbalx.com/Mephisto/XR-06-Javelin-Eve-Lander-and-Ascent-Vehicle XR-06 Ranger Mk III "Grand Tour" SSTA (standalone version without Eve lander)https://kerbalx.com/Mephisto/XR-06-Ranger-Mk-III-Grand-Tour-SSTA Mephisto. (Who wants to be a testpilot? Send the Interns!) Quote Link to comment Share on other sites More sharing options...
MisterKerman Posted August 2, 2018 Share Posted August 2, 2018 (edited) Very Excited! I just docked my first 4 Kerbal Capacity (5 if you include the pilot) Shuttle to my 120KM Circ Orbital fuel station. I used the profile you provided Mephisto. It fits my plane great. I need to balance fuel ratios as I appear to have brought too much oxidizer... @Mephisto81 Edited August 2, 2018 by MisterKerman Quote Link to comment Share on other sites More sharing options...
Mephisto81 Posted August 4, 2018 Share Posted August 4, 2018 Nice one. Glad to be of service. :) Quote Link to comment Share on other sites More sharing options...
MinerEdgar Posted August 10, 2018 Share Posted August 10, 2018 The Flash SP, a development of my SSSSTO design. (Stupid Simple Single Stage to Orbit, The Rockomax Jumbo 64 plus a Skipper) I gotta find away to elegantly include a docking port on this. Quote Link to comment Share on other sites More sharing options...
banderling Posted September 16, 2018 Share Posted September 16, 2018 (edited) Edited September 16, 2018 by banderling Quote Link to comment Share on other sites More sharing options...
Scarecrow Posted September 16, 2018 Share Posted September 16, 2018 (edited) This is my latest SSTO. Designed to perform the simple function of transferring crew to and from my LKO station. Edited September 16, 2018 by Scarecrow Quote Link to comment Share on other sites More sharing options...
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