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Here is my attempt to make a craft with 90 sepratrons. Well, 56 of them, in three rings around a very lightweight core. There is no room for luxuries such as attitude control, gimballing or RCS, so going in a straight line is not a guaranteed outcome. [IMGUR]BLxT6[/IMGUR] I claim 900 m/s. I might improve this a bit later. Edit: well, there's an improvement. Eight more engines, wheels locked and on all sides. [IMGUR]yaiD3[/IMGUR] New best: 980 m/s.

After many, many hours in Kerbal Space Program I finally feel ready to take on one of the most beautiful challenges. The new parts in 1.0.5 give me the possibility to create something that was not possible before: a small refueling explorer! I present you the Fuzzy Lama, flown by star engineer kerbonaut Bill Kerman. I really like flying it, just 69 tons fully fueled, very easy to fly in the atmosphere and phenomenal range in space. Part 1: Kerbal Space Center to Minmus: Next parts will follow when I have time, probably in the weekend.

Build a craft that can go to Minmus surface without staging and includes an ISRU converter and drills. Once you're there, the rest of the Kerbol system is open for you.

I wonder if you could save mass on the Jool trip by not taking a command pod with you. If it's only needed for Kerbin reentry, then maybe you could leave it behind in LKO and rendezvous later.

Slightly lower price, one part less, slightly heavier, but altogether a significant improvement on the combined ranking. LordCorwin, your hard work and tight margins have showed result, congratulations. Anyone want to try a solid rocket booster approach again?

OpenWorldAddict and LordCorwin, very nice entries, you have been added to the rankings! LordCorwin, I'm surprised you almost beat my weight record with a full capsule to escape velocity. I feel that Rid_14 or Rid_15 will take the overall title, unless NikkyD is working on something better too. By the way, NikkyD, there's nothing stopping you from taking another person's design and improving it, as long as your changes are significant for the end result, you will be ranked.

Translated: This challenge is about piloting skills: land a craft (stock or mod parts, doesn't matter) from Minmus orbit to the surface and take off again. You may not use SAS during any point. All reaction wheels must be switched off. All rcs thrusters must be switched off. Your only attitude control can come from the gimballing of your main engines (all of which must be pointed in the same direction). Piloting aids such as Mechjeb are also obviously not allowed. Entrants should preferably show their skills through an uploaded video, but an image album with plenty of pictures can also work. If there are multiple entries and people feel the need to be ranked and outdo each other, I suggest using fewer engines, more complicated craft, or a lower TWR. Maybe someone can even show us a landing without any gimballed engines!

No, simply lower is better. And actually there's no need to divide by the best result, since then we're dividing all by the same factor. Leaderboard updated, including the following entry: The Mini-bus! Not so cheap, quite some parts, but the lowest mass by a margin. I probably can't win my own challenge, but I'll give it a try in the rank I'm best at. Pad mass is 4,0905t, 13 parts and it costs 11826. The first stage tank is partially empty to save some weight. After Jeb climbing in the Rapier is started and released when it reaches 40 kN. Mini-bus goes diagonal, and just after mach 1 the engine is throttled back by half. Throttling back up at 11 km, flame-out speed is a very respectable 1620 m/s due to its high TWR. A parking orbit is entered. Not a very precise one, because the centre of mass is not exactly in the middle, and there are no reaction wheels. I aimed for the moon, but because of the lack of precision I missed. But there was enough delta-v to send Jebediah on a long trip. So 4,0905 tons, 13 parts, 11826 funds.

RoeddipusHex, I have no doubt that your craft can make it, but I would like to see some stats and one screenshot of it achieving Kerbin escape velocity. Thank you for all the nice entries! NikkyD and th3Jimmer, your entries have been added to the leaderboard and top the charts. Foxster and NikkyD, your entries have been disqualified for using a mod that is against the spirit of this challenge. Rule 1 "1. One launch only, no help from any spacecraft not part of the launch." implies that if you want to use a chair, you still have to include a capsule on the launch pad. But I'll start a separate "Take Command" leaderboard for you, since this is Jebediah we are talking about. LordCorwin, rule 6: "No abuse of physics glitches and bugs. No use of EVA rocketpack." Jebediah is not that stupid. A new ranking has been added! The Kerbals are very happy with all your suggestions, and they will decide by combining the three rankings in the following way: each result is divided by the current leader's result, and the three are multiplied to achieve a combined score. NikkyD is currently leading with 1, 7/2 and 1 giving 3,5.

Very nice entries! NikkyD, an innovative way to use a seat while keeping to the single launch. I just wonder if it isn't difficult to fly a rocket with a seat as a nose. Also, you used 9 parts, did I count correctly?

Nice one, ihtoit. When another modded entry appears, I will open a leaderboard for mod entries. Which mods did you use?

I have a similar problem, while still on the launch pad the radial decouplers start heating up rapidly without any reason, and reach 2000K in half a minute and explode. I removed the side boosters and put them on again at the exact same spot, and all was fine. Then in a next iteration of the rocket the radial decouplers heat up and explode again. This was in 1.0.3. I have just upgraded to 1.0.4 but I haven't checked yet if the problem is gone. It seems like some sort of weird feedback loop in the thermal system.

Aw man, I worked so hard on my assisted launch technique, and turns out it can be beaten with wings that easily... congratulations Nao, I will try to beat your record next!

Finally! The Assisted Launch Primarily Airbreathing Cargo Ascender (abbreviated A.L.P.A.C.A.) has made it to orbit! And the magic number is... 44,56%! Click the spoiler tag to see how it is done. The A.L.P.A.C.A. is a descendant of the Alpacalypse 2, with slightly more fuel but 55% more payload. It's takeoff mass is 41,185, and the payload mass is 18,35. I took extra care to add an extra reaction wheel and battery on the core stage, since the Aerospike doesn't have gimballing, and we're not allowed to use the payload's torque or battery. Rapiers seem the way to go for highest efficiency, flaming out at higher speed and altitude than Whiplashes. But the limiting factor is always their static TWR. For example the Rapiers on the A.L.P.A.C.A. give it a TWR of 1,04 when completely spooled up. So how does this take off? By assisted launch! When the Rapiers reach 70% thrust, the Aerospike is switched on and drains fuel from the two FLT-100's in the booster stages. This burn only lasts 18 seconds, but that is enough to bring the Rapiers to 140 m/s, after which their thrust only increases. The sound barrier is broken in 47 seconds. Jeb tries to keep a 20 degree pitch. The cockpit is getting a little warm at max Q, but nothing that Jebediah can't handle. On this launch air runs out slightly before fuel, 47 fuel units left over in the side boosters. After staging the core stage takes over, also recharging the battery (Rapiers don't have alternators). Jeb looks quite happy. With its low TWR of 0,69 raising apogee takes a while, but staging velocity was high enough that the thrust doesn't have to be pointed away from prograde. When the Aerospike is shut down, the A.L.P.A.C.A.'s orbit actually has a perigee! A 59 m/s burn was enough to circularise the orbit. 6 fuel units are left. Content with a mission accomplished, Jeb undocks the 18,35 tons of payload. So can this be improved upon? Seeing as I had tiny amounts of fuel left in both stages, 45% should be possible, maybe 45,5% with a larger rocket profiting from scale efficiencies. But I don't see 1.0.2's 55% as possible in any way. Here is what such a larger rocket would look like: 4 full ore tanks, large reaction wheel instead of small, X-200 32 and X-200 16 instead of C7 adapter and FLT-400, Skipper instead of Aerospike, and 8 boosters instead of 2. Delta-v and TWR numbers all look the same, and payload fraction is 45,28%. But I'm not going to launch it, because it has 84 parts and it would take hours to reach orbit.

I have made a rocket with about 46,5% efficiency, but I just came short 20m/s at circularisation. A few more tries and I can show you.