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Decided to make a couple of ssrt LKO reusable booster designs as they can look pretty sleek with the new cargobays. This is one of my intermediate designs, able to lift about ~25t's in to LKO with an efficient orbit burn along with a well executed suicide burn. Tho once the cargobay bugs are fixed, i imagine it should be capable of lifting more. Ive also considered adding dedicated vacuum engines, but i felt like it kinda ruined the ''sleek'' design. Specs: Mass: 246 / 48t Parts: 33 Engines: 4 vectors LKO Lift capacity: 25t Craft file: https://www.mediafire.com/file/sl5gwxuexidzoj5/ssrt_v3_various_takeoff.json/file

I'm going to build a reusable ship to go to Jool and back, that has to have the ability to reenter LKO. My current design I'm working on has about 10,000 m/s and I'm wondering if that's enough for the mission it'll have to undertake.

Friends, I have just published the long-awaited v2 upgrade to the venerable Minotaur Super Tanker at KerbalX [link]. The Minotaur v2: it chops, it dices, it slices, it mulches, it mows the lawn, it walks the dog -- and it boosts 39 kilo-kallons of LF to LKO. [It does not play the piano.] And now with nosecones!! (Ja, Werner was right all along...) It has the grunt and an ample top deck for heavy-lifting of additional payload. It can go inter-planetary. You can even build a super-ugly orbital gas station unpainted in a dull, orange, anti-knock safety color (thoroughly tested by Kerbals) from the first two you send up [subject of next video]. It has a power train for Massive Ion Drive. Get yours now as there are only a virtual number remaining...

Happy New Year, everyone. I am overhauling my fleet and I'm in the market for ideas about orbital fuel dumps (OFD). Let's define an OFD as an orbital vehicle (Kerbin or elsewhere) that serves the sole two purposes of: refueling visiting vessels; (possibly) keeping mission components docked together awaiting final (low orbit) assembly; (not looking beautiful [in Space, nobody can see how Ugly you are]) I gave up on space stations as anything more than a fuel dump long ago. I've recently upgraded to 1.2 and then 1.3 and find auto-strutting -- which is just a way to defeat the ugly side of the Unity physics engine (as best I can gather) -- does actually help. But I still can't risk docking very much to the OFD (pictured). And have to remain very observant with the Warp key lest tragedy befall. What have people found is the best way to put a pile of fuel into orbit and keep it stocked?? Pictured below, (BEWARE THE UGLINESS), I assemble the following from bits left over from two super-tanker launches. Each super-tanker lofts 165 kilotons of LF up to the OFD. You can see this OFD has two weak links, at the hubs. I find that just maneuvering a ship near it can cause it to get the shakes. Even auto-strutted. And I'm not terribly sure which kind of strutting (Root, Parent, Grandparent, Heaviest) ought to work best... Please post screenshots of your Orange Fuel Dumps...!!

This challenge is simple. We all start with the exact same rocket, patterned after a Delta IV Heavy (I'll explain why in a moment). We all have the same payload: three large ore holding tanks and a probe core. The challenge is to fill the ore tanks as full as you can and still make orbit with a periapsis over 85 km. Here's the rocket (you can build it yourself in a few moments): Three orange tanks with Skipper engines, large nose cones on the side tanks, Rockomax and TT-70 decouplers, a Poodle upper stage engine, an X200-16 upper stage tank, and the smallest probe core. I suggest autostrutting everything. Since we all have the same rocket, this challenge will come down to piloting and nothing else. I chose the Delta IV Heavy design because it introduces a range of variables associated with throttling down the core engine or transferring fuel in order to maximize effective dV. The amount of ore you choose to attempt will greatly affect TWR, which will change your gravity turn accordingly. I chose 85x85 (or greater) to add an additional variable as far as lofted trajectories are concerned. Obviously, no MechJeb or other piloting mods. Good luck!

Save fuel by flying a stock gravity turn to orbit This is a competition in KSP version 1.2.1 to launch the stock "Kerbal 1-5" from the KSC launch pad to low Kerbin orbit, with as much fuel left over as possible. Motivation for challenge My interest for this topic recently rearose when this question was asked and discussed. I haven't played much recently, but I remember how difficult I found it to estimate the fuel needed to get to orbit back in KSP ver. 1.0.4. According to the guides and forum posts you are supposed to fly a gravity turn to save as much fuel as possible. Most of the posts I found however aren't necessarily entirely up to date to the newest KSP versions. We will soon get KSP ver. 1.2, and then while the modders are busy updating mods I thought I would get someone to answer the above question, by kerbally kunningly masking it as a 'challenge'. In short, I am curious how much fuel I should expect to have left once the Kerbal 1-5 reaches LKO. At first I had less than 30 units of liquid fuel left (the near vertical approach). Now I am up to a shade over 40 units. It can probably be improved substantially still. I will soon add detailed rules (none of the easy tricks, like adjusting the thrust limiter, are allowed), and explain the scoring (a slight variation on the number of unused liquid fuel units). Vanilla rules The idea is to find out just how much fuel the stock "Kerbal 1-5" rocket model has left, when flown to low Kerbin orbit as suggested by the design. When I say suggested by the design, I mean that the strange extra docking port should stay on, and the thrust limiters should stay in place too. Attempts should be flown in KSP version 1.2.1 1.2 without any physics changing mods. Difficulty settings that may affect the flight must be at the default values; i.e. re-entry heating must be at 100 %, and changes in the debug menus are not allowed. The launch takes place from the KSC launch pad. Any time of day is acceptable as the launch time. The vessel is the stock "Kerbal 1-5" manned by one kerbal. Changes to staging is not allowed; neither is manually staging/ejecting/activating the staged parts. You may not tweak the stock vessel in any way; in particular you must leave the thrust limiters in place. An exception to the above rule is that you are allowed to lock and unlock the engine gimbals (and/or change the gimbal limits). You are also allowed to change, disable and enable the reaction wheel mode to suit your flying style. You are not allowed to use the RCS; all of the monopropellant must be spared. Neither are you allowed to go on EVA or bump into other crafts. The target orbit is an eastbound equatorial orbit of Kerbin at 80 km ASL. Your orbit is, however, allowed to be any orbit of Kerbin with periapsis and apoapsis both at or above 80'000 m. You may manipulate the throttle as you wish, and you may take any path to space/orbit that you think best, as long as you don't leave the Kerbin SoI. You are allowed to take advantage of SAS, autopilot mods and custom instruments (e.g. time to apoapsis and inclination read outs). Challenge participation reports and scoring When submitting results please report all of the following. The challenge entry category. "Vanilla": The main/nominal category. The one described in this section. "FAR": Using the FAR (aerodynamics) mod. See below. "GOaP": The "Get Out and Push" category. See below. Any control automation used. "AP": If you utilized an autopilot of sorts. Please tell us about the settings you chose, particular if you manage to find a particular efficient gravity turn strategy. "SAS": If you did not use an autopilot, but did engage the stock SAS. "Manual": If you flew the entire mission by hand (and without SAS). The number of liquid fuel units left on board, once in orbit. The periapsis and apoapsis of your orbit. Visible heating during flight. I don't think the stock Kerbal 1-5 is prone to heat issues, but maybe visible heat effects are a byproduct of an optimal gravity turn. Please let us know if you notice heat effects, and try to describe their 'severity'. Anything out of the ordinary. Are you for instance launching at a particular time of day to take advantage of the hot (and less dense) atmosphere. Your score is based on the amount of liquid fuel left (in your FL-T400 fuel tank) when your orbit is established. In the nominal category ("Vanilla"), the score is adjusted slightly for your actual achieved periapsis and apoapsis, and given as a percentage. A percentage score is the more action packed option for a competition! The score formula is presented in a thread of its own, so that it may be discussed separately. The score formula for the stock configured Kerbal 1-5 will give you a score of roughly 15 % if you have 15 units of liquid fuel left (poor efficiency), and roughly 70 % if you have 70 units left (outstanding efficiency). The scale is not linear. Getting into (80 km) orbit with no fuel left is enough to score above 3 %, and a shade over 90 units are required to get a perfect, and probably impossible, score of 100 %. [Note: the score formula may yet be adjusted to accommodate changes introduced in KSP ver. 1.2; the score formula is updated for KSP ver. 1.2.1]. The corrections for actual periapsis and apoapsis is given for periapsis above 80 km and below 100 km and apoapsis above 80 km and below 120 km. The idea is that if your gravity turn happens to have a build-in overshoot, then you will not have wasted all of that overshoot energy (i.e. fuel) in regards to your score. All else being equal you will loose some points though, compared to a tighter cheaper alternative. The corrections are made because the challenge should not primarily be about who can hit 80 km with the greatest precision. Entries in the "FAR" and "GOaP" categories are not adjusted for periapsis or apoapsis. The unadjusted scores ("FAR" and "GOaP") are exactly the number of liquid fuel units left in orbit. The percentage score formula is used only for entries in the nominal ("Vanilla") category. FAR ladder rules GOaP intro There are already a few good (and surprisingly sane) entries in the "Get Out and Push" (GOaP) category, so let us write some 'formal' rules for the GOaP challenge part. A group of dry and boring optimizer consultants have visited the Kerbal Space Center recently. Their report suggests to reduce the number of Rapid Unplanned Disassembly events and to layoff Kerbals. After reading the report Max L. Kerman quickly drew up calculations showing that the savings necessary to solve the current funding crisis can be achieved by a combination of flying more efficient gravity turns and a bit of creative tinkering. It is now up to you to show that the Sunday launches of the Kerbal 1-5 are not just leisure trips to orbit, but in fact important "In Orbit Fuel Contingency Reserve" missions. You do that by displaying that the Kerbal 1-5 has a viable amount of fuel, that it may function as an orbital refueler, i.e. have as much fuel as possible left over once in orbit. Not all of the tinkering is quite aboveboard, so there are restrictions as to which actions you may perform below 1000 m above sea level. GOaP rules Leader board (vanilla template) Eidahlil; 39.22 %; KSP 1.2 Gordon Fecyk; 37.66 %; KSP 1.2.1 (video included) tg626; 33.37 %; KSP 1.2 (a touch below 80 km) emaier138; 31.32 %; KSP 1.2 tseitsei89; 41.37 %; KSP 1.1.3 (score suspended) mk1980; 41.29 %; KSP 1.1.3 (score suspended) "Name"; "Efficienty score"; Comment Leader board (FAR and GOaP)

So I noticed last week that I only needed something like 200 delta-V to get from a keosynchronous orbit at 2800 km to Munar orbit. And it got me thinking. I know for interplanetary transfers Oberth effect is a big thing, but what's the real difference between a 100km orbit and a 1000 km orbit in terms of Oberth effect? Also, for transfers within the Kerbin-Mun-Minmus system, I know in theory you're losing a bit of dV going from a Hohman transfer to a round orbit, and then from that round orbit to another Hohman transfer -- you should be losing roughly as much dV as you're spending to circularize, unless your first Hohman transfer was pointing in the wrong direction (at which point it's a wash). Is this intuitive answer anywhere near correct?

Hi guys, I was trying to design a spaceship/spaceplane hybrid that is similar to Dyna-Soar. I've managed to get it into LKO, rendezvous with my space station and return to Kerbin. It survived the re-entry pretty well, but the issue came right after the re-entry: prograde pointed right towards the ground, and my ship started tumbling like a washing machine. Would really appreciate some help if somebody could guide me on what's wrong with the plane. (I've checked the COM and COL, COL is constantly behind the COM even when the tank is empty. Thanks!

So the idea is to launch a payload to LKO with as low funds/ton as possible. There will be 3 categories: 1. Disposable lifters. No recovery 2. Recovery allowed. No airbreathers 3. Anything goes Some general rules: 1. Stock only. Visual and informative mods are ok. 2. No cheat menu or other funny business. 3. You must launch from launch pad or runway. 4. You must achieve a stable orbit. Pe >70km. 5. Payload must be separated from the lifter once in orbit. Decoupler used for this can NOT be a part of the payload. 6. Payload can have 1 pod, cockpit or probe core but nothing else that contributes any thrust, fuel or control authority to your craft. Also no lifting surfaces in payload. 7. Your score is (funds you used - payload price - recovery costs in categories 2 &3)/(payload mass in tons) 8. Screenshots or video required. 1. DISPOSABLE LIFTERS 1. You don't get any funds from recovery. 2. You can use ANY stock parts you like. 2. RECOVERABLE. NO AIRBREATHING ENGINES 1. You can use any stock parts except airbreathing engines. 2.You can recover any parts of your lifter that you can for a refund. 3. If you return parts of the lifter from orbit you don't have to land on runway or launchpad for 100% refund. Just land somewhere on kerbin and you can count 100% refund. This is because (IMO) once you are in orbit it is trivial (but time consuming and boring/irritating) to land at KSC. 4. If you return parts of the lifter that are dropped while suborbital or in atmosphere you must land them somewhere in the KSC area (not necessarily on the launchpad/runway) for 100% refund (KSC must be within sight from your landing spot). This is because again precision landing is boring/irritating. But now you can't land anywhere you want since while suborbital/still in atmosphere it is not necessarily trivial to get anywhere near KSC. 3. ANYTHING GOES 1. You can use any stock parts. 2.You can recover any parts of your lifter that you can for a refund. 3. If you return parts of the lifter from orbit you don't have to land on runway or launchpad for 100% refund. Just land somewhere on kerbin and you can count 100% refund. This is because (IMO) once you are in orbit it is trivial (but time consuming and boring/irritating) to land at KSC. 4. If you return parts of the lifter that are dropped while suborbital or in atmosphere you must land them somewhere in the KSC area (not necessarily on the launchpad/runway) for 100% refund (KSC must be within sight from your landing spot). This is because again precision landing is boring/irritating. But now you can't land anywhere you want since while suborbital/still in atmosphere it is not necessarily trivial to get anywhere near KSC. LEADERBOARDS: DISPOSABLE: 1. Tseitsei89 636.17 2. Maccollo 642.10 3. Cunjo Carl 753.50 RECOVERABLE. NO AIRBREATHERS: 1.Tseitsei 312.78 2. 3. ANYTHING GOES: 1. Tseitsei89 83.11 2. 3. And here is my entry for the disposable category to start things off: 103 436 total cost 25 028 payload cost 117.15 tons payload mass => 669.30 funds per tonne Flight profile: 1. Start all engines 2. Tilt a little bit towards east to start gravity turn using twin boars gimbal and click prograde hold on 3. At around 120m/s shut down twin boar 4. When SRBs burn out you should be tilted at about 40 degree mark (see screenshots). You can activate twin boar again when SRBs are still burning if you threaten to tilt over too quickly. 5. After SRB separation just keep burning prograde and try to hold your "time to Ap" at about half of your remaining "burn time". 6. When your Ap is >70km shut down engine. At this point your Pe should already be positive or at least very close to zero if you flew well. 7. Coast to Ap and circularize.

It looks like the Δv needed to reach low Kerbin orbit from KSC went down recently from 4,550 m/s to under 3,600. I've seen references in the forum that suggest that this is due to the new aerodynamics modeling in 1.0.4(?), but can anyone explain why?