swjr-swis

You shouldn't need to: the whole idea is to load a craft in a recent version and let KSP's own loading code resolve the issues. If the craft loads at all, all the parts will show up with their current counterparts. This may however have unexpected effects, like gaps between parts etc. That's the challenge. Additionally, there are also stat differences: some parts will load with old numbers for tank volume, heat resistance, drag values. It should be interesting indeed.

"I choose you, KerbalX." Available to all, independent of whatever store they bought KSP from. Purpose-made for the job, by a KSP player. Wins hands down in my view. A suggestion for those who prefer Steam Workshop because 'it does this or that better': have you tried letting @katateochi know that you would like to see a particular feature? He's been known to make changes or implement new features based on user feedback. It might prove a bit harder to get Valve to make changes to the Workshop...

I just now noticed I completely missed this part. This means you do not have the delta wing section unlocked yet, or the elevon-2/3. My apologies, that makes the rear section of the wings invalid. Luckily, two small delta wings and a type C wing give us a composite delta wing too, and the elevon-1 can fulfill the task of the others. The Prototype 2B (link updated) should now only use parts from the tech nodes you have available. It's a few more parts in total, and a tiny bit less efficient/rigid, but performance and handling is for all purposes identical to the 2A.

That's usually the part I most look forward to in new challenges...

From the first screenshot you posted, I thought so too. It looked very close to being capable of meaningful LKO operation. Since a lot of the (generally good) advice given suggest rather hefty changes to your craft, I decided to see how close I could stay to your own design and still make it work. Whether I succeeded in keeping to your original concept will be debatable, but I think it at least showcases a few basic tweaks for spaceplane construction. A cave at: I rebuilt your craft in 1.3.1 from the first screenshot you provided, since you didn't share the craft file. Some things can't be seen well enough (cargo bay content) or at all (main gear placement/configuration) so I had to free-form those parts. Tl;dr: the Prototype 2B (note: link updated) carries a 2.3t cargo to a 100km orbit with full (extra) mono tanks for rendezvous and docking operations, spare LFO for orbital maneuvering and reentry burn, and a bit of extra LF for powered flight time on the return. It's also easy to keep stable, even with empty tanks - with all other tanks empty, using the last 50-ish units of mono does shift the CoM a tiny bit behind the CoL, but it can still be controlled well, and in normal operation this should hardly ever happen). I first rebuilt it as closely as I could to yours, to keep track of what I ended up changing. A list of the changes, more or less in order of positive effect: Your craft was sorely lacking lift, even with added AoI - so I replaced all six (visible?) wing sections by bigger ones: delta wings in the rear and structural wing type A for the two forward sections. With double the trailing wing edge, I also replaced the single elevon-1 by an elevon-2 (roll) and elevon-3 (pitch), for separate roll/pitch control and more control authority. Angle of incidence on the wings. A very simple yet very effective improvement. For a spaceplane, you can simply start (and often suffice) with giving the rotate gizmo one fine 'click' (5 degrees) of positive incidence. I did this to all the fixed surfaces, then shifted them a few fine offset 'clicks' up/down as needed to get them more blended again. Note that all the gizmo adjustments I did were with snap on - a lot of fine-tuning is possible, but this demonstrates that some very basic rule-of-thumb changes can already make a huge difference. I also added a bit of camber to the wings (outer edge of the wing rotated one fine click, 5 degrees, up) - this helps with stability during flight and reentry. The two circular intakes on the side stacks are relatively draggy and are not very heat resistant. I replaced them by a NCS + small nose cone. With full tanks, there is way too much liquid fuel for a basic roundtrip to LKO and back. Jets use a fraction of the fuel units that rocket engines do - it pays to watch during a trial run how much your set of engines need to get to their maximum speed/altitude, and then keep your LF as close to that amount as possible, with a bit to spare for safety margin. All that LF is basically dead weight costing dV if it stays unused. So I replaced the engine nacelles by FL-T400 LFO tank. To restore air intake, I added an XM-G50 radial intake on top. I added nose cones to the back of the Swivels and offset them forward. Besides making a cleaner visual for a spaceplane, it also plugs the open stack nodes and removes some more drag (a 'KSP physics' quirk). I replaced all RCS thruster blocks by two 6-way balls of linear ports, one on the nose and one between the Swivels. This gives full RCS translation, and leaves roll to the reaction wheel. Additionally, the front ball affords the cockpit enough heat protection for LKO roundtrips. The single rudder wasn't able to control sideslip, so I doubled the delta winglet, moving them back, down, and to the sides. I added deployment to the brake action group, so they function as airbrakes too. After a few test flights I decided there was too much LFO for the swivels, so I replaced the Mk2 LFO fuselage by a second short cargo bay (assuming that you don't yet have the larger cargo bay unlocked). Without that surplus LFO, the plane now has a larger more useful cargo space, and it can carry more payload mass to orbit. I could not see well enough into your cargo bay to replicate it, so I added a 1.25m reaction wheel (more efficient than the two small ones I can see), a 1.25m mono tank, and a 1.25m docking port to the front node of the bay. Radially attached to those I added batteries, solar panels, antenna, and lights. There was also room for some small radiators (attached to the crew cabin then offset into the bay) to help cool the cabin and cockpit a bit faster once in space. On the back node of the bay I added a Jr docking port and another light. The cargo space was now large enough for an FL-T400 LFO tank with ports, so I added one and fully fueled it as test payload (2.3t). The resulting build makes it to LKO with a respectable payload (refuel pod? station module? orbital telescope?), almost without need of manual inputs, and is fully operational once in orbit. It holds its angle of attack very well during reentry, transitions gracefully into a glide, and is easy to land softly. The landing gear springs may need a bit of tweaking - it does like to bounce up from the runway a bit. Aside from the clearly larger wings and the side stack tops, I think this still retains most of your design/concept - let me know what you think. There's still some gains to be had from further tweaking, but as it is, I think it's already a very functional tech tier-6 spaceplane. (P.S.: if you prefer I don't share the craft, just let me know and I will remove the KerbalX page. It's your concept, no hard feelings.)

Vessel mover is a mod, I'm guessing? Or is it one of the new DLC things? Tip is appreciated, but it is moot now: OP has clarified (not when I thought, reading is still a skill) that a launch clamp is allowed below 100m, which allows me to do this and keep my game stock. Now to find a few moments to finish this in between stuff that supposedly has 'higher priority'...

Hmm, hadn't considered that. Reverting and launching time and again to tweak things, it's a pain the rear to have to separately 'launch' a kerbal in a pod on the launch pad and walk to the runway every time. I'll save that for the final launch.

Genuine question: how did you load the kerbal without using either a launch clamp or a mod? I have a tiny winged plane that manages to beat your climb numbers, but the only way I can get it manned and launched properly in my stock game is by using a launch clamp, which is explicitly excluded by rule 4.1, and we're not allowed mods other than autopilots.

A combination effect of 1) deploying four pairs of actual airbrakes, 2) the pair of rudders with opposing deployment, and 3) the rear service bay opening, adding the drag of the bay and all science parts contained within. Tip: that last one is a very effective and compact aerobrake solution for a 1.25m stack: stock a bay with several 'discs' of 6 elevon-4 in 6-way radial symmetry, offset inwards so the elevons are neatly enclosed when the bay is closed (zero drag). During reentry or aerobraking, just open the bay and all elevons will suddenly be subjected to the full effects of drag, which is maximized by the elevons being perpendicular to the airflow. Additionally, the bay and stack still shield the elevons from heating. No mods, it's all pure stock. The window in which I created the waypoint is the stock debug menu (Alt-F12 on PC/Win), the waypoint indicator on the navball appears when rightclicking a waypoint on the map view to 'enable navigation'. The KerbNet window is a stock rightclick (or action group) option on probe cores (there's a small core in the forward service bay). The smaller window is the stock rightclick part action window of the surface scanning module at the top of the rear service bay.

I adapted one of my seaplanes for this challenge, recorded the run, then promptly forgot all about it until a recent post from Klapaucius reminded me of this. Better late than never. Craft file: https://kerbalx.com/swjr-swis/SeaPlane-One-B1 Still pics on the imgur album: https://imgur.com/a/SohfMJn

I think you confused me with @bewing there... you are quoting him. This reminds me that I've done your Mountain Lake Challenge a while back now, and still haven't gotten around to uploading the seaplane I created for it, or the movie to document the challenge attempt. That thread has a distinct lack of proper seaplane pontoons!

It looks like you don't have 'Advanced Tweakables' on in your settings - the screenshot does not show the usual fuel flow priority controls in the part action menu. Go into your settings and enable them, then you can prioritize the tanks you want emptied first (higher numbers get drained first). They can work for jets too - if you have tanks on opposite sides of no-crossfeed parts. But in this case, as @bewing says, they should not be necessary: jets will drain from all tanks on the craft that they can 'reach'. Side benefit: fuel lines are draggy, so don't use them if not absolutely necessary.

The questions looked like a challenge to me, so I voted for the ones you tagged most improbable. It was surprisingly easy... I like messing with statisticians. My therapists hated me too.

I'm glad this explains the differences between your and Cupcake's experience, but I would not quite phrase this as 'fixed'. F5/F9 is not required in 1.3.1 and before to 'fix' phantom drag that should not be there to begin with.

You can just barely fit two kerbals side by side without clipping their helmets into each other, and still keep them visually within a 1.25m diameter part (like the service bay), by offsetting the seats down from center (somewhere between 2 and 3 fine offset 'clicks'). The kerbals and the seats will be fully shielded from drag or heat. Keep in mind though that when leaving the seats, they are displaced up and forward, which can clip them inside parts of your lander and sometimes causes violent forces. I uploaded a subassembly of the arrangement, because it requires a bit of snapless offset adjustment: Subassembly file: https://kerbalx.com/swjr-swis/2-seat-125m-bay More pics on the above link. My experience is that service bays (and fairings) tend to have the same results: being destroyed before the kerbals in a crash tends to make the kerbals survive the ordeal. Not always, but definitely adds to the survival rate.

My calculation was based on conservation of energy too. Since you dump the engines at flame-out on the way up and the rest of the trajectory is unpowered, the speed at that point is the absolute maximum you can hope to have when crossing that same altitude on the way down, assuming zero drag losses during the arc and perfect transformations from kinetic to potential and back again. We don't even need to know how high you can get from there, it's already set by the flame-out point. Then it's just a matter of calculating how much gravity can add to the speed from the flame-out altitude to sea level , again assuming zero drag loss (v-final squared = v-initial squared times 2g times altitude). That is the limit. Unless I got my physics messed up. I was trying to do math at 4am again, so it's possible.

Post that single-engine rocket! It deserves the nr 1 spot for using minimal engines, even if at the same speed. Less engines should definitely get a bonus. I know the craft I entered can do it with less engines, it is over-powered for the purpose - it just made a visually pleasing arrangement.

@neistridlar Some encouraging evidence, I hope: In trying out your flight profile with a stripped down version of my JunoSpeeder-3c (no gear, elevons or command seat, launched vertically), I managed to capture a splashdown at 821.1 m/s. It was a split second too late and the craft is already destroyed in the screenshot, so it doesn't serve as proof for the leaderboard, but it proves you right: there is opportunity to side-step the Juno flame-out limit. My craft did have the advantage over yours that it still has its engines and some spare fuel on the way down, and there is a brief section of the descent where the Junos do kick in (between 16-13km), which recovers some drag losses up to that point. Below that, free-fall velocity never dips below flame-out limit anymore so they are of no further help. Still, the vertical flight profile can get to at least 821 (and perhaps even a bit higher). Game on!

Edit: I removed the previous entry posted here. I missed the part where it said it had to transport a kerbal. In its place I post a two-stage rocket that uses only Terrier engines to lift a kerbal to LKO and bring it back safely again. It was made for a different challenge, but it is valid for this one too. Full imgur album: https://imgur.com/a/39fzZ4n Craft file: https://kerbalx.com/swjr-swis/Terrier2LKO-1b

850 m/s... that would mean having a velocity of 600 m/s when crossing the 18.5km mark on the way up (and assuming zero drag to get that exact same speed at that point on the way down). But the Juno flame-out speed at that altitude is much lower, closer to 500 m/s, if you manage to even get full thrust up to there and don't flame-out before. That maximum flame-out speed/moment is going to be the same regardless of how sleek the craft is: the limit is set by the Juno, not the terminal velocity. Theoretically there is a bit of margin - using an experimental flame-out of 590 m/s at 17350m (all values rounded up), you could get a theoretical max in a zero drag environment of 830 m/s (rounded up) when crashing into the ocean. I don't think those 10 m/s are enough to counter the drag losses though. All that said: it's an interesting approach and I'm curious to see if it pays off.

That looks like it should be able to get there, but it's still being held back by the tiniest bit of body drag. Try replacing the two basic fins by Elevon-4's (maybe even just a single one, centered), with Pitch/Yaw/Roll disabled, with just the bare minimum deployment deflection to keep it level when over 800m/s. The reaction wheel can handle attitude control, use the elevon(s) purely for the tiny lift needed to stay perfectly prograde. It may sound silly to swap to a 'wing' that offers less than half the lift of what you use now, but being able to control the deployment angle 'live', starting with a bit more for take-off and subsonic then slowly tapering off as it accelerates, you can maintain the optimum lift to drag ration all the way up to flame-out. I think you linked the wrong image. The speed read-out says 807.3 on that screenshot.

4 is plenty.

The placement really doesn't matter, at least up to 1.3.1, but I'm quite sure they did not change that in 1.4 either. Something else must account for the difference you noticed. A quick test to prove it to yourself:

Does not work. Heat and drag are treated very differently in KSP. To the game, parts are fully 'transparent' to drag, regardless of how they are attached or what's 'in front of' or around them, with the exception of bays/fairings. The things that do matter: shielding inside a bay or fairing (but not always! I'm looking at you, Mk2 bay corner spaces and wheels/gear) plugging stack attachment nodes (don't forget engines with bottom attachment nodes) making opposite nodes as similar as possible (some 'size X' nodes are more equal than others) minimizing the cross-section size and nr. of stacks placing parts as 'prograde' as possible (even when it visually -and logically- looks like that would only cause more drag - like most radially attached parts on cones) choosing the least draggy top/bottom stack parts angle of incidence on wings... seriously (keep the body of the craft prograde) make full use of the in-game Physics/Aero displays to find out the counter-intuitive results of tweaks on your design (less/smaller parts = more drag, sometimes ) It's not simply a matter of adding more engines. It's been tried. Ever since the Juno was introduced.

Two reasons: force of habit, and because I could. I play with G-force effects enabled, so I always put a probe core in my craft to keep control when the pilots pass out. This craft doesn't just fly in a straight line, it can also bank and loop-the-loop at ludicrous speeds without breaking up - many kerbal lives were (temporarily) saved by that core while testing the capabilities of the craft. Additionally, since the core is shielded from drag anyway, and the craft has more power than it really needs (l simply copied the outer ring engine subassembly from the 3b version, and it so happened to make a pleasing arrangement), removing the core to minimize drag/mass was not required to allow max speed.