ManEatingApe

@IncongruousGoat Ditching the landing gear to save parts on your Laythe lander was ingenious. Climbing atop the flag to get back on your Tylo lander was also a nice touch - I chuckled at that one, it was very Kerbal!

Presenting the Ark B, a no MH, no ISRU, no gravity assists, no added preservatives, no added flavorings, stock chemical engine only Jool 5 mission. @5thHorseman's Tylo technique was just so good, that I followed it to the letter, dropping a mother-ship into high Tylo orbit. Thanks 5H! For maximum part re-use the centre stage of the Tylo lander returned to the mother-ship and was refuelled and reused as the Vall, Bop and Pol lander. The Laythe landing craft also did double duty as the Kerbin return vehicle. Highlights in the spoiler and full album link.

Here's a pure 1.4.5 stock (no MH, no ISRU) entry: Life, the Universe and Eve-returning Mission profile was straightforward. The main vessel aero-braked into Eve capture, detaching a small return vessel that remained in orbit just before final descent. Jeb went to the surface at 66m altitude and returned in a lander that could reliably almost reach orbit from below 300m. After Jeb valiantly jet-packed the remaining couple hundred m/s, Valentina retrieved him with the return vessel and returned home safely. Eve descent/ascent highlights in the spoiler and full album here. In a truly Arthur Dent level of absent-mindedness I forgot to uninstall Hyperedit until halfway through the challenge when landed on Eve. Of course I didn't use it at any point during the mission proper, however @dnbattley if you feel that disqualifies the attempt then no worries.

Nothing like a bit of competitive provocation! @swjr-swis's rocket entry is going to be hard to beat, but the field is wide open for a spaceplane entry.

Such extravagance!

No frills 25 Terrier entry The first stage only lifts the craft a few hundred meters but it's enough. It feels like doing an Eve ascent...only on Kerbin instead! By 6km things are ticking over nicely In LKO with a little fuel left over so that we can bring Jeb back. Full album link This does allow an easy way to rank the entries - the fewer Terriers the better.

Keep it simple - really simple. Ruthlessly strip away anything that's not necessary in order to minimise drag and mass. For example, do you need that rudder? A fixed stabiliser can suffice. Here's a primitive SSTO: Some specific tips: Add some incidence (1 to 2°) to your main wings. This will help generate lift while reducing drag by keeping your body more prograde. Experiment with different ascent profiles to get the most out of your design. Some threads that might help: Caveman Tech SSTO Challenge Tech level 7 SSTO to Minmus surface and back

Thanks, the gap is the middle is mostly for fun That's a nice looking craft, hope you're going to submit an entry with it!

I had an absolute blast with this challenge. Never really delved too deeply into the mining and ISRU aspects of KSP before, so this was a nice excuse to give these a try. Learned some new things: Don't forget your parachute radiators. Finding good concentrations of ore takes time and effort. Small ore tanks do not like 4km aero-braking. Without further ado, here's a sub 25 ton spaceplane entry. Mining and refuelling on Laythe at 5% efficiency took over a year. 3 PB-NUKs provided constant reliable power. An engineer could have sped this up, but the high power requirements of running at 125% pushed the mass of the craft up too much. Seconding @Laie's experience, take off with full ore tanks was sloooow. My technique consisted of driving off the edge of a cliff and desperately trying not to hit the ground. Once in LLO, I found I had miscalculated horribly and only had 1,150 m/s dV left. Enough for a Kerbin transfer but not enough to brake successfully. Normally a sequence of gravity assists could whittle the orbit down but the challenge time limit prevented that. A suitably Kerbal workaround was to convert 1/3 of our precious ore to fuel while in orbit, gaining another 400 m/s dV. A Tylo gravity assist flung Jeb to Kerbin for the bargain basement price of 670 m/s. Re-entry was too brisk to capture on the first pass, but diving as low as possible into the atmosphere gave a handy Oberth bonus. That slowed the craft down enough that a small 40 m/s adjustment gave a 1:1 resonant orbit with Kerbin and an aero-capture was (just) about possible on the 2nd pass. 4 small tanks of ore delivered to Kerbin in 9 years, 100 days. Full album link with more details. @Nozza Nice work on your first challenge - it's both tricky and thoroughly enjoyable The time limit adds a nice pressure. You have to mine quickly enough to get back in time and also bring enough dV to return to Kerbin without the aid of multiple gravity assists.

Fantastic! Bop and Pol landings plus 3 flybys is a great achievement - you've set a new bar for Caveman interplanetary shenanigans!

This challenge is coming together nicely...could I suggest a little more time allowed, say 10 years? 6 years is pretty tight, even with direct Hohmann transfers and doesn't leave much wiggle room to derp around the Jool system.

I found anything over 2 sections tall to be unmanageably wobbly, so to mitigate I built out sideways instead. Even then it was touch and go! Any kind of gravity turn was out of the question - I simply burned straight up until the side boosters were empty. One nice thing is that the docking ports can be re-staged as decouplers, saving a few parts. Things got calmer with the second stage This design manages to put about 11 tons into LKO. Full construction album link

Anything that uses reaction engines is a no-go (even if technically the Kerbal is the reaction mass ) However some kind of rover wheel based linear accelerator would work. Pushing the boundaries of Kerbal flinging is one of the challenge's aspects. I'd love to see some pics of the contraption!

That would be spectacular and very Kerbal! I suggest that you give this a read Doing some quick sums - to get to 5km altitude (neglecting air resistance) you'd want fling your victim at √(2*9.81*5000) = 313 m/s However Kerbals have a fair bit of drag, so flinging a small aerodynamic craft might work better. The good news is that if you could build something capable of flinging at those speeds you could set a new time record!

I like this idea - how about a series of weight classes? Entries would be ranked within the same class. Weight would be counted as mass on launchpad/runway. For multiple launches just sum the weights. (For fairness I'd suggest no launching empty and ISRU refuelling on Kerbin's surface.) Was thinking something like: 10 tons or less Flyweight 25 tons or less Bantamweight 50 tons or less Featherweight 75 tons or less Lightweight 100 tons or less Welterweight 150 tons or less Middleweight 250 tons or less Cruiserweight 500 tons or less Heavyweight 1000 tons or less Super Heavyweight