bayesian_acolyte

It's kind of crazy how even the voting has been on the first question. With 16 votes cast by 9 people, no option has more than 3 votes. There's only around 6 hours left before the poll ends, so hopefully someone breaks the 3 way tie.

People can submit whatever entrants they want and I will include them in the OP, just not on the official scoreboard. If recent challenges are any guide, there probably won't be too many entrants, so I don't want to split things up into multiple categories. The challenge is to take off from Eve and land on Tylo. I'll edit the OP to make this more clear. Whether "quickly" is part of the equation or not is being determined by the poll. This challenge was never from Moho, the original thread creator just made things a bit confusing by talking about their previous challenge from Moho in their opening sentence.

Here's a trip report album with lots of pictures: https://imgur.com/a/toExeBc I did this mission for this challenge: The goal was to get 4 Kerbals to Eve and back with the heaviest payload launched from Kerbin being as light as possible. My heaviest payload was 3.021 tons. A few of the mission restrictions were: 6 launches max No ISRU with Kerbals present No command chairs between SOI transitions Must launch into 40 degree inclination orbit (optional bonus) No parachutes (optional bonus) Here's the craft file for the ship that was put together in orbit: https://kerbalx.com/Bayesian_Acolyte/Salvo-to-Eve-complete-ship

This challenge entails lifting off from Eve and then landing on Tylo. After this poll closes, I will create a new challenge thread, and whatever options are ahead at that time will be the main rules and scoring criteria. The poll is open until 11:59 pm on Monday, April 15th (not sure which time zone it's using). This poll is an extension of this thread: Hyperedit or similar mods will be allowed to move the craft to the start location on Eve. I was thinking of limiting launches to below 2km above sea level but that rule is open for negotiation. Other than that I'd like to use a fairly standard rule set (only stock parts, limited clipping, etc).

If we take your decoupler and land/take off rule at face value, the best way to do this is probably pretty far from what you had in mind. It's easy to do staging without decouplers. Get an ion craft in a highly elliptical orbit, accelerate for tens of hours, and barely dip into the atmosphere. Then decelerate for tens of hours and parachute back down on Kerbin. But it seems you meant to say that the ship needs to be 100% reusable, and can land and then take off from most places ("anywhere" would be ridiculous, good luck landing in the middle of a cliff face). The best ships for the latter interpretations of your rules would be a high dV SSTO, probably with ISRU as well. Take off from Kerbin, refuel on Minmus, accelerate hard towards Kerbin, barely dip into the atmosphere, decelerate and take a bunch of aerobraking passes before landing. But your "Kerbin only" rule is ambiguous. If you meant that you can't leave Kerbin's atmosphere instead of just the speed record has to be set on Kerbin, the best ship will be a huge rocket SSTO with lots of dV that will accelerate a ton perpendicular to Kerbin at 69km, and then do a breaking burn so that it doesn't leave the atmosphere before gliding back down.

That's a very good point. Speed doesn't quite scale linearly with dV though, especially when close to minimizing dV. For example according to this calculator, lowest dV from Eve to Jool with certain assumptions is around 4.6k at ~900 days travel time. But increasing that dV to just 5k can get you there in under 700 days, and for 6k dV 500 days is possible. But after that the dV costs do start increasing rapidly in a more linear fashion. This might mean that everyone just picks the sweet spot around 400-550 days, which wouldn't be that interesting, but would still add something over a straight cost challenge. Edit: I also considered giving the time portion an exponent, but I'm worried that would be very difficult to balance, and either time or cost would still end up dominating anyways. Do you have any suggestions? It would be nice if speed was a significant factor since I've done a number of mass and cost challenges so far but nothing where speed was a factor. However making it only speed presents clear mass explosion problems. And I don't like just putting a mass limit since that presents its own problems, and I'm not sure that would get entrants. I'm not married to the speed idea though, I think the challenge is interesting enough without it, I mostly just want people to participate. Whatever rules would make people want to do it are the rules I want.

Since this idea seems to have been abandoned, I'd like to revive it in a new thread. The tentative rules I favor are: -A Small Holding Tank filled with ore (weighing 3.5 tons) needs to be transported from the surface of Eve to the surface of Tylo. The mission does not need to be manned and CommNet can be disabled. -Score is mission time multiplied by cost. Lowest score wins. I think speed vs cost presents some interesting trade offs and design decisions. The holding tank rule adds a further twist and prevents the usual recycled command chair or command pod upper stage designs. I'll wait around 48 hours before creating the thread so that people can have a chance to comment and OP can have a chance to reclaim the idea if they want. Would anyone be interested in doing this? If not, is there a way to change the proposed rules so you would be interested?

I would probably do it like I did the clipped version, land in the sea and then boat back to land. There's an island south west of the DeGrasse that's not overly far away. The clipped ship was actually capable of a dolphin takeoff for most of its development, but I eliminated a pair of control surfaces on the nose in one of the last cuts for cost saving reasons, and after that it couldn't get its nose far enough down to dive. I think on this version the upward tilted wings would prevent diving, but they would be a huge help in a sea takeoff. My guess is that some control surface canards would allow the nose to come up enough to take off on water, maybe even replacing the rear control surfaces.

It took a few tries and some tweaks but I got to stable orbit with enough dV for Minmus. The changes from the above screenshot were adding two yaw stabilizers, tilting all lift surfaces up 5 degrees, moving the high-drag ore tank back, and emptying one liquid fuel tank. The flight strategy was follow prograde to 20 degrees from runway, then tilt back down to horizon slightly before reaching 10km. Next after gaining a bit of speed, gradually tilt up to around 30 degrees until engine burn out. The NERVE was started up at around 15km. At around 30km, start to gradually tilt up more, eventually going all the way to 67 degree tilt at around 60km which was held until vertical velocity mercifully stopped decreasing at around 15 m/s at ~68km. Then tilt was gradually lowered, aiming to freeze vertical velocity at 5-10 m/s once above 70km until stable orbit was achieved. The mk1 body looks kind of crappy compared to the cool mk2 design in the above video, but I believe there are drag advantages, especially when having to tilt hard away from prograde in the atmosphere to get enough vertical thrust. Using minimal wing surface area is also important.

I've completed my entry. Here's a trip report album: https://imgur.com/a/toExeBc Here are the craft files for each launch: http://s000.tinyupload.com/?file_id=84687377789748419987 My highest weight launch was 3.021 tons and my lowest weight was 3.010 tons. I believe I qualify for the 5% bonuses Tilt-A-Whirl, Ares 1, Bird of Prey, and Home Sweet Home, along with the 15% bonus Don't Chute. I'm not completely sure I qualify for Don't Chute as my LES system had a parachute (which was only used during testing) and I accidentally brought a stowaway during orbital assembly which had zero impact on the overall mission but whose safe return to Kerbin involved his paraglider. Assuming I qualify for the above bonuses, my final score is 3.021*.95^4*.85 = 2.092 tons. Lastly here's a screenshot of the main put-together craft fully fueled. This craft can be found at https://kerbalx.com/Bayesian_Acolyte/Salvo-to-Eve-complete-ship

I'm at the stage where I'm trying to land in a good spot on Eve. My lander/ascender is terrible at surviving atmospheric entry on Eve and needs a long approach, which means getting to the right landing spot intact is a time consuming process. I'm starting to wish I had sacrificed some weight to make it easier.

Under the fairing (attached to the nose cone) is a decoupler attached to a probe core, ore container, and goo. The ore container is filled up on Laythe and then brought to the site. The decoupler is detached, and the contraption sinks to the bottom with the probe core on hibernation mode. The sample is taken at the bottom, and then the ore container is emptied, allowing it to rise and the sample to be collected. Yep, refuel at Minmus, refuel before and after the mission on Laythe, and then refuel on Pol.

I now see that my clipping in my original entry was a lot more norm-violating than I had initially thought. I have recently participated in a few other challenges that don't mention clipping in the rules, but nobody is trying anything similar to my entry. Chalk it up to inexperience. FWIW I think the most meaningful clipping in the entry was the engines being on top of each other. The 4 clipped mk1 fuel tanks improved handling and durability but not drag or afaik anything else, which means that without that clipping it would be more difficult to fly but would have similar capabilities. On the other hand the engines being on top of each other is the only way to have both with thrust pointed at center mass and allows the body to have a cross section of only a single mk1. The non-clipping solution is to add a second Whiplash and move them to the sides. The added weight would drop the vacuum dV to ~4k, so another fuel tank is added (4k dV might be barely enough for this mission but would be very difficult). With these and a few other minor changes the overall performance on paper is mostly superior to the original version, with slightly increased dV and ~65% more atmospheric TWR, but ~20% less vacuum TWR. Final cost is just over 30k. I haven't flown it yet so some tweaks might be needed (too little air intake?) but it should be able to accomplish this mission without undue hardship. Maybe I'll give it a go after I'm done with Salvo to Eve.

Thanks for the quick reply. I decided to take your advice and run a few tests which confirmed everything you said. First I de-orbited the craft, turned the visual drag indicators to max, and zoomed in on the struts as the craft plummeted to its demise. I didn't see any drag. IIRC physicless parts still show drag on themselves instead of on the parent but I'm not 100% on this. Second I added up my exact mass of compnent crafts and compared them to the completed product, which was easy since I hadn't burned any fuel. I did notice an extra 50 kg for each remaining strut. Normally that amount of extra weight would be negligible, but it might make the difference for this craft. Re-launch it is.

I launched a few spaceship pieces to be assembled in orbit without realizing that the ends of the struts used to stabalize the payloads when launching would be left behind. I'm trying to complete a challenge from the challenge forum, and my design has thin margins (light weight Eve ascent vehicle). All my testing was done without these strut ends, and I'm worried that if they have any physics impact it might kill the mission. I understand struts themselves are physicsless parts but adding their properties to the parent part could have a significant impact. Launching the ship parts again without any struts and re-assembling it wouldn't be too difficult, but I'm lazy and curious. Do strut remnants have any physics impact on the craft they are attached to?

Banning ions might be best, and I somewhat agree with your main point, but the rule as it currently stands is more reasonable than you are making it out to be. The line is drawn at intent. If the main purpose of the prograde burn is to make an interplanetary burn easier, that is not allowed. If however the main craft is in an orbit between Mun and Minmus, and ion engines are used to bring crew out to that orbit to transfer to the main craft, that is allowed. If a small craft is put in a far out orbit just so that you have an excuse to use ion engines to rendezvous with it, and the real goal is to use ion engines to increase apoapsis to make the Eve burn easier, that is not allowed. There are edge cases where the line can get ambiguous, but if you are intentionally creating these edge cases to take advantage of using ions, that is not allowed. This does put pretty severe restrictions on the use of ions so that they are close to being banned. EDIT: At least that's my reading of the rule, I don't speak for OP.

Is it possible to get this bonus without Making History? For example, by using Hyperedit to move launch vehicles to the coordinates? And if so, can we do docking in Kerbin's SOI at a less-inclined angle as long as all fuel/engines/everything used is "payload" and not part of the launch vehicle? IMO the most difficult part of Pro Pilot is the command seat aspect, which alone is probably worth 15%+. Getting 6 launches and not being allowed to use ISRU with the main crew changes the ISRU equation. It definitely still has advantages depending on mission design but not nearly as much as in a normal weight minimization challenge. All that being said, I wouldn't be opposed to separate ISRU and command seat bonuses. Also it might be possible to do ISRU with pro pilot, you would just have to bring out an extra Kerbal before hand. The rule states "...before your Kerbals are launched" which might mean the main crew Kerbals, and doing it with a pre-crew pilot Kerbal might be allowed, although this could use some clarification. Aren't command chairs on SOI transitions explicitly forbidden in the rules? And even if they weren't, 5% seems quite light for this. Agreed on this. EDIT @sevenperforce since this reply was posted seconds after yours, the main reason I'm not a fan of the airlock is from a balance perspective. When lifting is free, weight in interplanetary travel is far more meaningful than size, so it provides a significant advantage. And from a purely selfish perspective, the airlock would shave a lot of weight off of my current working design, but I don't have MH and can't use it. Isn't this impossible without significant clipping? Speaking of which, maybe it would be best to elucidate the clipping rules. There seems to be an understood ethos among veterans of which clipping is and isn't acceptable, but there also appears to be some minor variations, and spelling it out would help us noobs.

Cool challenge! I look forward to participating. I've got a few (probably noob-y) clarifying questions: I think I understand this one except that I'm not sure what "0-0" means? Just want to make sure it's not adding some requirement I'm not aware of. Does this only apply to the Kerbed landings on Eve and Kerbin? For example if we land a rover on Eve using wings/wheels, but the Kerbals use a standard parachute, would this qualify for the Eve portion? What exactly counts as payload? Can we add dummy weight to our lightest launches to equalize them? What would be the requirements for this dummy weight to be considered "payload"? Do we have to use default Comm Network settings or can we turn it off? Also I assume we aren't allowed to strand or kill any pilot Kerbals, and that they can't count as main crew unless they are launched with the last launch?

Ya, I figured this was the case, and I regret not doing this, but the realization came too late. I came very close to asking in this thread if I could hyper-edit a new craft into the same Eve orbit and fuel situation as my old one with the addition of a small parachute. But I wanted to minimize the use of H, and without it I figured it would take more time to get the new craft into position (including the aerobreaking) than it would to just land the craft I had. I can upload the ~120 save files I made if that helps. The shortage of ascent pictures was largely because there were a number of failed attempts and I didn't know which would work, and I wasn't sure how useful the failed attempt pictures would be. And then the ones I did get, I forgot to show the fuel tab. But the launch shouldn't be too hard to reproduce, I think I ended up making stable orbit like ~5 times loaded on ore if you include a few test launches, and I'm not the best pilot. This is an interesting question, the short answer is that I did detach them as soon as they emptied. In my initial testing (before the official launch) I was mixing it up with both strategies, and the two times I achieved orbit I was dropping them immediately, so I just went with it. However I don't think I ever got the right ascent profile when I was holding the tanks longer, and there's a good chance the success of the former strategy was just due to chance. The TWR is around 1.4 at launch, and then goes up to around 1.75 before the first tanks are released, then goes back down to 1.4 after they are released. The TWR would continue to climb above 2 depending on how many tanks are held. It's an interesting theory question, is the extra drag and weight worth the higher TWR? Initially I suspected it would be but I never took the time to investigate properly, since I had verified I could achieve a successful launch that met my goals and that was good enough. The dV of the final Eve ascent stage is around 1650m/s including the ore, which is much more manageable than 2500m/s. In one successful test launch my initial AP never made it out of the atmosphere and I fell past it. but was able to raise the far-side PE past the atmosphere to the new AP and then circularize on the other side. And then on the official launch I used, my initial AP was raised to 130 km, so I know a wide variety of launch profiles are possible. I suspect the more shallow launch is optimal, freezing time-to-ap just before reaching it, as it gives a lot of burn time for the final stage and minimizes waste thrust. The craft is quite controllable in this stage so you can tilt up as soon as the the stage is activated to slow the time to AP, and if you can freeze it without too steep of an angle that is going to be a successful launch. Here's a picture of a launch that achieved stable orbit (but with not enough remaining dV to meet the depot) despite AP being only 6 seconds away and 65km with 1150m/s dV remaining in the final stage, because I was able to freeze time-to-AP with a 45 degree angle.

At long last I've completed this challenge with a ship costing barely less than 300k, excluding return value. Imgur album: https://imgur.com/a/m4gkADk Craft file: https://kerbalx.com/Bayesian_Acolyte/24-Asparagus-Flavored-Boars I used 12 twin boars for most of the fuel storage and engine power, trying to take full advantage of their low cost. 3 Darts served as my main interplanetary engines as well as my upper stage on Eve ascent. One notable difference between my strategy and others was my decision to exclude parachutes for cost saving purposes. This worked out in the end but was quite frustrating and is not something I would repeat. My route was the same as others, Minmus -> Eve orbit -> fuel drop -> Eve touchdown -> re-fuel in orbit after ascent -> Gilly -> home. Details are in the imgur album linked above. Thank you @Laie for the cool challenge and @ManEatingApe for the inspiration for the design. Your cost reduction by decreasing the use of Mammoths and increasing the amount of Twin Boars is what inspired this design.

You can use this page to tell: https://kerbalx.com/hoioh/Runway-speeder/parts It looks like the canrds are alright and there's a single offending part called "hlfSrf", whatever that is.

@5thHorseman nice work on achieving a stable orbit, very impressive. Too bad that jerk who's running this challenge disallowed EVA pushing. I wonder if a solution might be to leave your periapsis barely in the atmosphere and have that slowly de-orbit you. There probably would still be enough time to collect all the science you would get from a stable orbit. It would be difficult to finesse the right orbit with SRBs though, and the de-orbiting process could take an annoyingly long amount of time.

I was cleaning out my screenshots folder and figured I might as well upload a trip report album for my attempt: https://imgur.com/a/NM96ghf

So being my noob self I didn't realize that Making History was needed to have the desert runway. I only discovered this on trying to land where Mechjeb had marked it. I landed anyways, but I understand this entry will not count. I also landed about half a degree of longitude short of the runway coordinates and had to reload the landing a few times due to bumpy ground and messed up break settings. This changed the f3 report, but it still shows the proper mission time of 8 minutes and 58 seconds: My cruising speed was 1710 to 1750 m/s at around 20km altitude. I was fighting overheating the whole way, often doing quick barrel rolls when it got too bad, and even lost my most forward wings due to overheating (with a max heat of 2400) which might disqualify my run if it wasn't already hopelessly disqualified. This was my first flight of this plane and it is not at all optimized for this challenge, exemplified by the fact that I still had half my fuel when I landed. Craft file: https://kerbalx.com/Bayesian_Acolyte/desert-speed-plane

By this logic any entry with no mods installed should also be illegal, since the stock debug menu performs the same functionality of moving ships in physically impossible ways.