StanK

Congratulations to @michal.don. Even though it is a quick build, your concept looks promising to me and satisfies this challenge's requirements. Rocket assisted landing on a short runway, or VTOL on a vacuum world could be benefits of this design. At the acceptable cost of looking a bit silly when pancaking through the last bit of atmosphere. @Physics Student, you'll need to land in one piece to be added to the Advanced Aviator list. Without returning safely and bragging about your mission at the Kerbal bar a badge would be useless anyway, right? I love the design though, so will mention that landing on parachutes is very much allowed - only the take off has to be horizontal. And thanks for the cockpit screenshot, just imagine sitting in that seat

That's a beauty @Physics Student. Did you also manage to land it in one piece? And now I'm asking for stuff, I would love to see a cockpit view after the flip if you've got one :-) This will be a nice design challenge, and I think possible. Perhaps using fuel pumping to initiate the flip. Just using jet fuel consumption will probably be too slow to get the effect fast enough. And Physycs Student's reverse probe core solution will help a lot too.

@Rosvall joins the list of Advanced Aviators with yet another creative design. Good work! Rolling to counter a small CoM/CoT misalignment is great plan too, and it evidently works. If it can be done in stock I don't know about it. It would be a great addition. I have not personally looked for a mod here so perhaps that is out there. I have two workarounds here if this is important for fuel distribution. First, the CoM is implicitly available, because it is the center of your screen. Zoom in as far as you can and you'll have a reasonable estimate. The CoL does not change for SSTOs (ignoring airbrakes). So if you put an object - like a radial battery - on the CoL, you can compare this to the zoomed in CoM and ensure aerodynamic stability before reentry. Second, lower trust so that SAS keeps the craft steady. Then you can see on the bottom left how much SAS needs to be steering. Pumping fuel around can change the CoM and the amount of steering required by SAS. When the dials indicate minimal steering, stop pumping fuel and increase trust. Repeat for the desired trust level

Well done @tsgaerospace! And that is a bold design to omit trust vectoring! I like how the aerospike seems to push the craft up, rather than forwards, into space when it's turned on. And indeed, landing anywhere on Kerbin is allowed, so this one counts.

That is an awesome entry @foobar. Congratulations on completing the challenge, and adding a new style for single jet+rocket development.

That is a good looking one @Wanderfound. Well done! And good to see there's room for passengers to enjoy the ride as well. Thanks @goduranus for showing it can land. And having reversed normal trust to break is a bonus. To show you my gratitude, you and previous Advanced Aviators can now wear a badge:

Good to hear the turbofan can survive re-entry, that would be the hard one to fix. My own attempt required some quick saving/loading as well to get the landing in-one-piece.

Nice one @Martian Emigrant, it's always good to see a practical use of the "thud" engine. And it can drive along too, you say? Mission complete! Thanks for the second entry @Scarecrow, that is exactly showing off the spaceplane design skills to keep that working that we are looking for. I didn't check before, but did you manage to land it safely in one piece as well? Frontal reverse turbofan. I did not believe it until I saw it @goduranus. Getting anything into space using a turbofans and atomic engines shows craftsmanship on it's own right. Did it also manage to come back to Kerbin's surface?

Congratulations @Scarecrow! You are the first to successfully finish the challenge. Coincidentally, I also grant you the honour to be the last do do so with a merged-rocket-and-jet or DIY-rapier solution. I will update the rules, and no longer allow this in the future - my apologies for this (also feel free to suggest how to clearly put this in a rule if my rule isn't). That's a great idea @goduranus, I did not think of that. Will you have enough trust and high altitude/velocity to create a viable SSTO though? Would be nice to see. As above, I'll update the rules for this as it is too similar to using a switching rapier.

Nice proof of concept @Sivonen, too bad fuel ran out just before orbit. I love the unusual shape, I have not seen an outline like that before.

Flipping at high velocity, from my archives: Album: http://imgur.com/a/PzIyi This could definitely work, but it will mess with the aerodynamics too. So I'll believe it when I see it.

That's a valid way to engage in this challenge. Although from my experience, "simply" is not. I'll have a dig in my archives and see if I can find the images for it.

To follow up on the famous K Prize, this challenge asks you to show off your master spaceplane design and flying skills. Build a spaceplane capable of reaching orbit, and returning safely using a single jet, and a single rocket engine. I have found this an interesting limitation that makes spaceplane design a lot harder. Mostly because the trust vectors are no longer trivially aligned with the CoM. Enjoy! Rules: The spaceplane must follow the rules as defined by the K Prize. In short: a horizontal take-off stock SSTO that can reach orbit(pe>70km) and land again in one piece. The provisions of the K Prize do apply to this challenge too. Use exactly 1 jet engine - defined as an engine that requires intake air and liquid fuel to run. Use exactly 1 rocket engine - defined as an engine that runs entirely on on-board fuel. An ion engine is also allowed. Rapier engines are allowed, but cannot switch mode during the flight and as such operate entirely as a jet, or entirely as a rocket engine. Merging/clipping/offsetting the two engines together into one is also not allowed (this is not much different from a mode switching rapier). Please remember to take pictures or a video as proof and for our enjoyment. Advanced Aviators: @Scarecrow - Rotate the engines, why not? @Martian Emigrant - The perfect case for a Thud @goduranus - Reverse trust in reverse @StanK - Me @Wanderfound - With spare seats @foobar - You can see through it @tsgaerospace - Pushed up into space @Rosvall - Rolling into space @michal.don - Pancake to accelerate! ...can proudly wear their badge: I have done a few times in past versions. To show it is still possible in 1.3 below is my own new entry: Album: http://imgur.com/a/dDIOT

Yes! +1

It just so happens I've got one laying around for this one The FlipFlop has been designed to do exactly this, with all the inconvenience that goes with it. And it is a fully functional SSTO - although with barely enough space to pack a toothbrush. No mods. If I have time I can go back and check what the "flip" time was. It should be around the 3 second mark at super-sonic speed. The design: The Flip: Full album at: http://imgur.com/a/PzIyi

I like the idea that the planets and moons should be different from each other. I would also like it if there's a reason to actually use rovers, or even planes on worlds with atmosphere. Start with a lone materials bay sitting on the surface. It can be 'operated' remotely by a Kerbal (scientist). Now imagine this thing was retextured/remodelled to look like a rock/special feature. And imagine it is not put there by you but generated. Now instead of scenic rocks, you have ones to interact with. Change the options to have something like 'observe rock' or 'take sample' Generate them far enough apart and a rover/plane will be useful and it will be fun to drive around, searching for one of these features. Also put them mostly in some, but not other, biomes/worlds and you have the diversity. E.g. a moon crater may have enough 'rocks' to land next to, but for Duna a rover starts making sense, and for Eve a plane.

She flies pretty badly, not to mention landing. Roll authority is surprisingly decent, but there is no such thing as yaw stability. A small price to pay... There are active controls though: ample RCS when almost out of control, fuel pumping to control CoM, and trust vectoring. Which all - now I write it down - explain why landing without fuel is so hard.

I am intrigued by building SSTOs with a single rocket and single jet engine, without resorting to rapiers. This is tricky because the two engines cannot be placed in a way that they both trust towards the center of mass, or can they.... . I proudly present to the forum: The Flip Flop! I'll be editing the video for it another day.

I wanted to try launching rockets from the air... And it worked! It was more of a proof of concept so far. Even though I added a parachute, I failed to add a solar panel, and forgot to think reentry through. So after a safe Mun and Minmus landing, the capsule made it back to Kerbin atmosphere only

Made it! To the mun's SOI using only SRBs that all fire at liftoff. I did reduce the trust in the VAB to make sure some made it until the end - and with a less than insane TWR. In total the probe visited the mun's SOI three times, with a fourth time warping glitched it out of that of Kerbin. To be honest, I was not sure on the details of what would be allowed in flight - starting engines, trust limiting etc. - and chose for this design. I thought to go with screenshots and SRBs are the easy way to prove there's no throttling, but I happened to record it and did forget to take any screenshots.

I would, but who has the time? Also, I updated the imgur album in the previous post. Within a kilometer from the exact pole the shadow does go a full circle, success!

To keep it basic, I thought to go for a sundial. To keep it complex, I thought that a pole would be the best place so it could last for the full day. Bill Brought three rovers, a '3', a '6', and one to put parts at 1, 2, 4, and 5. Lessons learnt: - Horizontal solar panels are not a good idea on the poles. - Ditched decouplers tend to explode on the polar surface. They do not make good clock markers. - Kerbol seems to shine from a single point, so it would need to be exactly on the pole, if this plan is at all possible. EDIT: Tests verify it should be possible on the exact north pole. Weird things happen there though, gravity is not what it used to.

Obviously, using a single jet and rocket engine is the most efficient way to build a SSTO, right? At least until the RAPIER, but my current career isn't there yet. It would have been simpler if there were two centers of mass to align the trust vectors with. But moving the center of lift way back did a similar trick.

Well, stay low, cannot be that hard, can it? Sure to do it won't be too hard, get there in time before the others eat all the snacks though...

Today I modified my asymmetrical plane, to become an asymmetrical space plane. Capable of asymmetrical docking and returning to the surface. Only two parts missing! Finally, while time accelerating for a shot in the rising sun, the ship was sacrificed for the Kraken, Sonzor was recovered but didn't remember a thing. More images can be found http://imgur.com/a/Ned6Y I also made my first post on this forum