Aetharan

I really hope not. I'm going to keep watching until they either cut the stream or launch the rocket, though.

I don't know whether to root for a successful, unexpected recovery of the booster (and subsequent museum interment) or for the big boom on the desert floor. Edit: 5 minutes into this hold, I'm going crazy with anticipation!

Just have to note: You dropped the Strander into the wrong category on both counts. It is manned and is not recoverable.

Okay, so I did some playing around with @Nefrums's "Small Boat" design, then decided to iterate a bit on it, and I managed a somewhat lighter version that doesn't have the pilot sticking out quite so far. Total mass 2.130t in the VAB, 2.224t with Meldun on board. Makes orbit at 70.0 km x 70.7 km, then re-enters and makes a desert landing via glide and suicide burn. It could go without the fins at all for 2.110t, but that makes liftoff very dicey to control. Edit: Another iteration knocks off the fins and cuts out 5 more units of fuel, producing a 2.085t Lawndart (2.179t Kerballed) that successfully orbits at 70.1 km x 70.8 km, re-enters, and after over a dozen reloads on final approach, splashes down safely in the ocean.

Hate to say it, but the game is using Metric tons, not the US ton. 2,264 Kg = 2.264t. He's got the Ogod-Y Mk.15b beat by a solid 0.15t, with the same amount of fuel in a heavier upper stage, but without the fairing for ascent that I've been relying on. It never occurred to me that the Mk.0 Fuselage plus a Radial Air Intake and an adapter would actually somehow be lighter than the Engine Pre-Cooler, but the trio come to 0.355 for a savings of 0.02t. The obvious weight-savings in the design difference is clearly the fairing, which makes up 0.157t of the Ogod-Y's bottom-stage mass (between both the shell and the base). What's blowing my mind is the fact that this accelerates at all. Just by appearance, it feels like it should be too blunt (with the intake flaring out like that) to work well, but clearly it does.

The only methods that I currently see for reducing weight for a manned mission below the mass of the Ogod-Y Mk.15b launch are as follows: 1) Dump the reaction wheel. This must be done by a pilot more skilled than I am, since all rotation would rely on the engines burning fuel, of which there was precious little left over by the suicide burn. 2) Replace the Spark with 4 or fewer Ants, as I did with the Strander: 4 can make orbit, and come in at 80% the mass of a Spark with a slightly higher ISP. It reduces the thrust-to-weight ratio of the upper stage dramatically, especially during the suicide-burn where you're going to need the thrust the most. Of course, that assumes that we don't go for a hatch-based shock absorber like Turbo Pumped did. This is obviously only my own view, which is limited, and I'm certain that somebody else has the skills necessary to pull it off. The way I look at it right now is simple: I want second place, and I want the person who beats me to do so only by building and flying something that nobody else can hope to beat. The narrower the margin between said craft and my own, the happier I'll be. Edit: Silly me. Ants don't have engine gimbals. You can beat the Spark's ISP and mass by going with a pair of Ants and a pair of Spiders, though. (290 + 315)/2=302.5. It's not much, but it's a slight boost in bang for your buck where fuel usage is concerned outside the atmosphere. Trying to go with only Ants on a ship with no reaction wheel... well, that's not going to space.

Of course, I'm sharing the part-lists and fuel amounts in these craft partly to help those who are competing against me, especially given the convergent evolution of my Ogod-Y and @EliteGuy3's Plankton design. The Ogod-Y upper stage is currently down to the same amount of fuel that could be held in two Oscar-Bs, and is only still using the ROUND 8 for its broader protection profile on reentry, and I don't really see a way to reduce the weight of the lifter much more, beyond (perhaps) chopping another 4 units of fuel off if it can still make it as high without them. That Pre-Cooler is pretty light as-is, especially given that it serves a dual-purpose as intake and fuel tank, and I'm using barely over half its capacity.

And there you see one of the reasons that my entries in this thread jumped from the Ogod-Y Mk.2 to the Ogod-Y Mk.14 without showing the intermediate iterations. The missing eleven were various degrees of "not enough fuel in the upper stage" and "can't survive reentry".

He'll update the leaderboard when he has time, I would assume. As for the one-upping: If you have, then I'm happy for you. I'll believe it when I see the gallery.

In the seat. Look at the sixth screenshot for a good view.

Well, phoo. Now I have to find some way to carve another 0.036t off of the Ogod-Y line! Edit: And done! The Ogod-Y Mk.15b weighs in at 2.320t unkerballed / 2.414 kerballed, makes an orbit of 70.0 km x 70.4 km, and re-enters for a suicide-burn water landing and recovery. Another Edit: We're starting to get down into the real-world weight range for large SUVs, rather than spacecraft, and have been there since roughly @foamyesque's launch.

I'll throw in our first entry for the Manned (but unrecoverable) board: the Strander Mk.1. Mass is 2.327t in the VAB, 2.421 on the pad with its zombie passenger. It ultimately achieves a circular orbit at 105 km, and isn't coming back down (lest we suffer a zombie apocalypse!)

Without the fairing, you need your re-entry to be shallow, and your Kerbal positioned very carefully behind sufficiently-large parts. I tried with just a pair of Oscar-Bs for fuel, and that's how I lost Jeb in this save-- they didn't provide him enough of a shadow. Edit: Rather than make a new post, I'll just add my update here. The Ogod-Y Mk.15 has made its flight, and I'm pretty sure I've hit the rock bottom weight for its design lineage at 2.390t unkerballed / 2.484t kerballed (I assume, anyway). No Mechjeb core on this one, instead relying on Kerbal Flight Data / Kerbal Flight Indicators. I may only have knocked another 0.054t off the weight of the previous iteration, but that's more than the weight of a Small Inline Reaction Wheel, and gives me more than the tiny hair I had last time on @foamyesque's MicroLaunch Orbiter 1. Another Edit: Yes, I lost the battery on landing. If deemed necessary, I'll take it on another flight, but there was a smidge of fuel still on board, and I really had flubbed the landing several times. I didn't even notice the broken part until just now, and I really hope that you don't make me try that landing another half-dozen times for this to count, since the rest of the 'pod' did make it. Nevermind. It's still there, it's just buried in Hillin's hind end.

As a side-note, you can see that I had fuel left after the suicide burn, and there was actually more fuel in the first stage when it ran out of air to breathe, so I could probably drop the mass a little bit more. Edit: Looking back over your posts, and comparing against my own experiences, the fact that you carry your fairing all the way up with you effectively negates the advantage you gain over my craft by excluding the small inline reaction wheel. I burn a little bit more of my launch weight on the fairing, but you have to expend more fuel than I do to make orbit because you keep yours long after I shed mine. Ultimately, I think the lightest we could get would be an Ogod-Y sans reaction wheel, using your superior piloting skill. Second Edit: The fairing base alone weighs 0.075t, and with a relatively tight cone of fairing that comes up to rougly 0.1t. The reaction wheel plus battery total 0.065t, so the ultimate question is whether keeping the fairing for aerodynamic efficiency makes enough of a difference when staging above 26 km to make up for the increased mass.

While I will cede that @foamyesque will always be able to build a lighter ship than mine until I can get over my reliance on reaction wheels for control, a whole load of experimentation has produced a vessel I can maintain control of which is lighter than the Micro-Orbiter, at 2.444t sans Kerbal. It makes it into orbit, then deorbits and comes in for a safe (powered) water-landing. Behold, the Ogod-Y Mk.14! Edit: Correcting which of Formyesque's ships I mentioned!

From what I can make of that challenge, it has little relevance here, especially with the changes that have been made to the game's aerodynamics and parts available since that time. Short of replicating each of the builds still visible there and testing whether it's still orbit-worthy in this version, and light enough to compete in its given category (unmanned or manned, recoverable or not), I'm not sure what the point was of bringing it up for discouragement.

My latest design keeps coming close, but not quite, and I know that it's entirely my own piloting failures. I'll give it a few more tries after I've eaten, but so far I've run out of fuel with numbers like AP 73 PE 67, AP 70 PE 60, AP 75 PE 55, and so on. If I can just get my ascent profile down perfect, I should be able to get it into orbit and have Jeb get out and push to deorbit if necessary.

@Bloojay The Ogod-Y only beat the Pram because I carried 5/6 the weight in fuel tanks, fuel, and engine that you did, and by going with the spark instead of 6 smaller engines, actually pulled off a lot more thrust at (assuming you used half ants and half spiders) roughly the same ISP. Since you DQ'd @foamyesque's entry for flubbing the landing, I'm going to aim for first to recover a manned craft weighing under 2.5t at launch.

Just a nitpick, but if the Ogod-Y and Up-Chucker lines are mutually exclusive on the same leaderboard, shouldn't @swjr-swis also only have one place in the Manned Recoverable category?

@foamyesque: Considering how long you've been at it, I'll take having designed and flown something only 8.9% heavier than your craft to be a minor victory in itself, especially given that I didn't know I was up against your suicidally-insane build in the first place. Edit: I will note that an Oscar-B and a Round 8 together have exactly the same mass and fuel capacity as the tank you're using, but in a more compact form-factor. It's what let me fit the whole upper stage in a straight-vertical fairing rather than having it flare out. Not sure how useful that will be in this particular challenge, but it's a design note to keep in mind for future tiny craft.

Beat again, and by only 0.219t! I must work harder! (Edit: And for the second time, I held 1st place for less than 5 minutes, meaning that the person who beat me was flying at the same time I was.) (Edit #2): I think this is where I bow out. To go lighter than @foamyesque, I'd have to go no chute / no reaction wheel like he did, and I just can't control my experimental craft that would have done it. My hat's off to you, bloke!

@Bloojay, I'm taking it back again (for however long it lasts this time): 2.676t unmanned, 2.770 on the pad with Val on board, 0.501 descent weight. I call it the "Ogod-Y", and this is the second iteration of the design. Makes a 71k circular orbit (with 0.000 eccentricity) with 186 delta-V left, and manages to come home safe for a splashdown.

...well, wow. At least I still have the lightest one that keeps its pilot enclosed on re-entry.

I'm-a taking the first slot back! At least, for a little while. The Up-Chucker Mk.6 weighs in at 3.570t unkerballed, 3.664 with a pilot on board, and 0.839 on final descent. Re-engineering for two-stage launches instead of three worked, and worked well! The craft doesn't even have an AR202 case, thanks to the presence of a probe core and the beauty of ModuleManager patches.

So, for command-seat craft, you're counting mass sans Kerbal for leaderboard listings?