Salvo to Eve: Distributed Launch Mission (NOW LIVE)

[herbal space program]

This looks like a fun and interesting challenge! I've been working on all kinds of stuff that's tangential to it, so I feel like I could cook up a decent entry without too much de-novo work.  Since it appears we get to make comments before the official launch, I do want to raise one issue about the rule on ions: "Ions can be used as tugs within a single SOI but they cannot be used for transfer burns. No endless periapsis-kicking."  This doesn't really make sense to me. Are you saying you're not allowed to used them to do any burns at all at your PE that raise your AP? What actually distinguishes using them as "tugs" vs. using them to do a transfer burn? If you just restrict their use to burns that end in the same SOI, you could still get yourself 99% of the way there with endless PE kicks and then use some other kind of engine to do the last little bit.  You could also just sort of gradually raise your orbit while keeping it more or less circular until you're nearly there. Sorting out all that potential controversy seems like it would be a big pain. For that reason, I think that if you really don't want people to use ions as their transfer stages, you should just ban them period. That's all they're really good for anyway, 

Edited March 31, 2019 by herbal space program

[FinalFan]

3 hours ago, herbal space program said:

This looks like a fun and interesting challenge! I've been working on all kinds of stuff that's tangential to it, so I feel like I could cook up a decent entry without too much de-novo work.  Since it appears we get to make comments before the official launch, I do want to raise one issue about the rule on ions: "Ions can be used as tugs within a single SOI but they cannot be used for transfer burns. No endless periapsis-kicking."  This doesn't really make sense to me. Are you saying you're not allowed to used them to do any burns at all at your PE that raise your AP? What actually distinguishes using them as "tugs" vs. using them to do a transfer burn? If you just restrict their use to burns that end in the same SOI, you could still get yourself 99% of the way there with endless PE kicks and then use some other kind of engine to do the last little bit.  You could also just sort of gradually raise your orbit while keeping it more or less circular until you're nearly there. Sorting out all that potential controversy seems like it would be a big pain. For that reason, I think that if you really don't want people to use ions as their transfer stages, you should just ban them period. That's all they're really good for anyway, 

Well, from context I think it's pretty clear that you would not be allowed to use your 99% idea, as that's directly against the explained motive for the rule.  And I also think you're perfectly aware of this.  But if someone wanted to use ions for some other purpose unrelated to the main transfer burn it's allowed.  I don't see why the ban should be broader than necessary.  

Wording it so as to be unassailable by the pickiest rules lawyer would indeed be a pain, but in a small contest where the judge is the Creator and available to answer questions I don't see a real problem.  

[Mr. Peabody]

On ‎3‎/‎29‎/‎2019 at 2:22 PM, sevenperforce said:

<snip>

Looks great! I may try this sometime.

[herbal space program]

22 hours ago, FinalFan said:

Well, from context I think it's pretty clear that you would not be allowed to use your 99% idea, as that's directly against the explained motive for the rule.  And I also think you're perfectly aware of this.  But if someone wanted to use ions for some other purpose unrelated to the main transfer burn it's allowed.  I don't see why the ban should be broader than necessary.  

Wording it so as to be unassailable by the pickiest rules lawyer would indeed be a pain, but in a small contest where the judge is the Creator and available to answer questions I don't see a real problem.  

My point, which you apparently missed, is  that there is no clear line at all  between uses other than for orbital transfers and using them for orbital transfers.  IOW, any time you use an engine while on orbit, you are transferring yourself to a different orbit, and if you do it in a prograde direction from a circular orbit, you are both doing a periapsis kick and using the engine to contribute to your ultimate ejection into a different SOI. So where do you draw the line between one such kick and "endless" ones? If you say you can't do any periapsis kicks at all, then the ions are literally useless. If however you just say that you have to keep all ion burns within the same SOI, then you are basically allowed to use ions for all but the last tiny bit of any particular transfer burn. Neither seems like a satisfactory rule based on what I construed OP's intent to be, and it's also not at all clear to me where where one could draw an unambiguous line between those two extremes that would prevent people from trying to use their ion engines for the only thing they're really useful for, which is to do low TWR, high-dV orbital transfers at 4200 ISP. You can cast aspersions about rules lawyers all you want, but this is not at all a trivial question, as it potentially has a large effect on how much mass the whole mission needs to have, which is a fundamental aspect of the scoring system. So my (I think sensible) suggestion was that if OP doesn't want people to use ions for the one and only thing they're really useful for, then OP should just ban them completely rather than contend with the potential headaches of people trying to push difficult-to-define boundaries. YMMV.

Edited April 2, 2019 by herbal space program

[bayesian_acolyte]

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.

46 minutes ago, herbal space program said:

So where do you draw the line between one such kick and "endless" ones?

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.

Edited April 1, 2019 by bayesian_acolyte

[FinalFan]

53 minutes ago, herbal space program said:

My point, which you apparently missed, is  that there is no clear line at all  between uses other than for orbital transfers and using them for orbital transfers.  IOW, any time you use an engine while on orbit, you are transferring yourself to a different orbit, and if you do it in a prograde direction from a circular orbit, you are both doing a periapsis kick and using the engine to contribute to your ultimate ejection into a different SOI. So where do you draw the line between one such kick and "endless" ones? If you say you can't do any periapsis kicks at all, then the ions are literally useless. If however you just say that you have to keep all ion burns within the same SOI, then you are basically allowed to use ions for all but the last tiny bit of any particular transfer burn. Neither seems like a satisfactory rule based on what I construed to be OP's intent to be, and it's also not at all clear to me where where one could draw an unambiguous line between those two extremes that would prevent people from trying to use their ion engines for the only thing they're really useful for, which is to do low TWR, high-dV orbital transfers at 4200 ISP. You can cast aspersions about rules lawyers all you want, but this is not at all a trivial question, as it potentially has a large effect on how much mass the whole mission needs to have, which is a fundamental aspect of the scoring system. So my (I think sensible) suggestion was that if OP doesn't want people to use ions for the one and only thing they're really useful for, then OP should just ban them completely. YMMV.

Okay, I will assume good faith here.  I had thought you were feigning a lack of understanding to highlight your argument, so I'm sorry for misunderstanding.  The way I see it is based on intent:  you are forbidden to use ions when your motive for the maneuver is to exit the SOI to go to another one.  So if your reason for the periapsis kick is to rendezvous with something else in the body's SOI, it is not a violation; if your reason is to leave the SOI, that's an inappropriate use according to the rule.  This includes the first of a set of 100 periapsis kicks where the goal is a completed transfer burn.  

Admittedly, this leaves a gray area where you could use ions for some in-SOI purpose that "just so happens" to leave you in a much higher orbit when you begin your burn.  In other words, cheating.  There are two answers to this that don't require a blanket ban:  one, simply the honor system; two, a modification to the rule saying ion use in-SOI should not leave you in an orbit more than 200km high, or more than 100km in altitude different from before ions were used, or something similar.  

Would such a rule modification clear up your questions regarding what is and isn't permissible ion usage?  (Please note that this is a hypothetical situation, since my interpretation isn't necessarily 100% the OP's intent.)

[edit:  bayesian_acolyte did a better job than me.]

Edited April 1, 2019 by FinalFan
Got upstaged :-0

[Laie]

On 3/31/2019 at 8:00 PM, sevenperforce said:

Pro Pilot is not intended to punish ISRU so much as it is intended to push users toward an Apollo architecture, to encourage people to send an additional Kerbal to hang out in Eve orbit. It also makes it challenging to do any orbital assembly beyond LKO because you need a pilot on both craft, potentially. 

Rendezvous on LV power is no great achievement. Pilot EVA's over and that's that. Or, given enough time and incentive, I guess you can dock with an inert target without RCS. Simply put: babysitting the orbiter should stand on it's own. Or perhaps mash it in with spacious accommodation, for housekeeping?

My main gripe with pro pilot is that it's incompatible with contingency, though, and 2/3rds of the benefit for little effort. It's a given with a straightforward single lander (which admittedly will score little else).

Regarding chairs and airlocks, I've edited my previous post with more data, but my opinion remains the same: airlocks should be treated as chairs, and "no chairs on ascent" should be made a bonus of it's own. Maybe degrade pro pilot for it.

Btw, "do not use chairs" -- not even on rovers? Or can we perhaps have two classes of rover? As I recall from Roads to Duna, you don't need much to build something that's technically a rover but of little practical use.

On 3/31/2019 at 8:01 PM, bayesian_acolyte said:

Is it possible to get this [tilt-a-whirl] without Making History?

Good one. Will assembly in any orbit over X inclination do?

 

[sevenperforce]

On 3/31/2019 at 2:01 PM, bayesian_acolyte said:

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?

If you want to use Hyperedit to launch from an altitude over 45 degrees, or simply launch directly into a Woomerang-accessible orbit from the KSC (per @Laie's idea), then that's fine. As long as your launch vehicle deposits your payload into an orbit inclined to 45 degrees (or more) then you earn Tilt-A-Whirl.

On 3/31/2019 at 2:01 PM, bayesian_acolyte said:

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. 

There could be a mission configuration where you send a fifth poor bloke ahead of all the others, to Gilly, and have him mine there before you launch the four who will ultimately land. I will mess around a little with the rules to add for some leeway in these areas...keep an eye out.

On 3/31/2019 at 2:01 PM, bayesian_acolyte said:

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.

I don't want to ban the inflatable airlock just because some people don't have MH; if I did, I might also have to ban the Mastodon because it's great for large Eve lifters, and from there I'd just be banning the whole MH expansion. What if we say that the airlock can be used off-planet (to satisfy Room to Move) but that for atmospheric ascent or descent you still need an actual capsule if you don't want to use command seats? This would temper the advantage somewhat and is also fairly realistic, since the original inflatable airlock was intended for use only in orbit.

On 3/31/2019 at 2:01 PM, bayesian_acolyte said:

...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.

Regarding clipping: I'm not too worried about it, honestly. If you're clipping for structural or aesthetic reasons, or to squeeze something just 2% more closely, it's no big deal. Just don't abuse it. If you find yourself cramming 43 Oscar-Bs into a small fairing or clipping engines wholly inside other engines, that's a bit much.

2 hours ago, herbal space program said:

My point, which you apparently missed, is  that there is no clear line at all  between uses other than for orbital transfers and using them for orbital transfers.  IOW, any time you use an engine while on orbit, you are transferring yourself to a different orbit, and if you do it in a prograde direction from a circular orbit, you are both doing a periapsis kick and using the engine to contribute to your ultimate ejection into a different SOI. So where do you draw the line between one such kick and "endless" ones? If you say you can't do any periapsis kicks at all, then the ions are literally useless. If however you just say that you have to keep all ion burns within the same SOI, then you are basically allowed to use ions for all but the last tiny bit of any particular transfer burn. Neither seems like a satisfactory rule based on what I construed to be OP's intent to be, and it's also not at all clear to me where where one could draw an unambiguous line between those two extremes that would prevent people from trying to use their ion engines for the only thing they're really useful for, which is to do low TWR, high-dV orbital transfers at 4200 ISP.

 

1 hour ago, FinalFan said:

Admittedly, this leaves a gray area where you could use ions for some in-SOI purpose that "just so happens" to leave you in a much higher orbit when you begin your burn.  In other words, cheating.  There are two answers to this that don't require a blanket ban:  one, simply the honor system; two, a modification to the rule saying ion use in-SOI should not leave you in an orbit more than 200km high, or more than 100km in altitude different from before ions were used, or something similar.  

Would such a rule modification clear up your questions regarding what is and isn't permissible ion usage?  (Please note that this is a hypothetical situation, since my interpretation isn't necessarily 100% the OP's intent.)

I'll update the rule to clarify. It will still have some dependence on the honor system but will narrow the field a little.

[herbal space program]

3 hours ago, sevenperforce said:

<snip>

I'll update the rule to clarify. It will still have some dependence on the honor system but will narrow the field a little.

FWIW, I think a good solution might be just to limit the total dV that can be provided by ions within any given SOI to some fixed value that is significantly less than the amount required to get from low orbit to escape. That would prevent people from doing all their orbital transfers on ions and also not be subject to any kind of ambiguous interpretation. Limiting the altitude at which they can be used might also achieve this, but that depends on how you feel about stuff like using them to send mining shuttles to Minmus to fuel stages that are on LKO. A dV-per-SOI limit would still make them useful for this, while an altitude limit would presumably need to be too low for that, since one that goes as high as Minmus would not really constitute much of a restriction.

....Thinking about it some more, you could also just limit the total amount of xenon the mission can employ to something that would be insufficient to lob the whole show out of Kerbin orbit. That would allow you to allocate it to smaller modules for the purposes of Minmus mining, etc. with a pretty free hand, but would still prevent you from using it as your primary means of getting the whole mission from LKO to Eve. It would also be very straightforward to enforce. I believe perhaps that may be the best way to achieve what you seem to want to do, based on what you've said about it thus far.

Edited April 2, 2019 by herbal space program

[herbal space program]

5 hours ago, FinalFan said:

Okay, I will assume good faith here.  I had thought you were feigning a lack of understanding to highlight your argument

I don't want to belabor this, but seriously,  you had no valid reason whatsoever to believe I was saying anything in bad faith. I have been on this forum for a very long time, and every single thing I have ever posted here is just a few clicks away if you'd care to look at it before passing judgment. Nuff said.

[sevenperforce]

The challenge is now live! Thanks again to everyone who participated in the commentary and discussion of the mission.

Re-read the rules carefully; I have tweaked a few parameters to enable some more creativity around mission planning. Good luck to all!

[Laie]

So that's how it is.... still a bit sad about how contingency rules out pro pilot. I wanted to show off by bringing two, but now I guess I'll have to try and combine as many tricks as possible in a single vessel. Orbital assembly, here I come!

[sevenperforce]

18 minutes ago, Laie said:

So that's how it is.... still a bit sad about how contingency rules out pro pilot. I wanted to show off by bringing two, but now I guess I'll have to try and combine as many tricks as possible in a single vessel. Orbital assembly, here I come!

Not entirely. You can send a lone Kerbal ahead to Minmus, mine a bunch of ore, and then launch your landing party to meet him low Eve orbit and do the refining there.

If your contingency lander has chutes, then you can program them to open at a particular altitude, stage them, then deorbit the lander with a piloted vehicle and let the contingency lander land itself.

Edited April 2, 2019 by sevenperforce

[FinalFan]

On 4/1/2019 at 7:50 PM, herbal space program said:

I don't want to belabor this, but seriously,  you had no valid reason whatsoever to believe I was saying anything in bad faith. I have been on this forum for a very long time, and every single thing I have ever posted here is just a few clicks away if you'd care to look at it before passing judgment. Nuff said.

Chalk it up to miscommunication from me to you.  Allow me to clarify:  your 99% proposal was such a blatant end run around (what I perceived to be) OP's clear intent that I did not think you, an apparently intelligent person, could in good faith actually think a mission using that technique would be accepted as a challenge entry.  

[Laie]

It's all quiet.... before the storm?

I don't want to show my hand just yet, or make a lot of noise about unlaid eggs, but as a quick heads-up: I'm on it, at the stage where the orbital assembly kit has been designed and I "only" need to fly the mission. So still several days, I guess, and only if I don't have to go back to the drawing board.

Anyone else doing this?

[bayesian_acolyte]

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.

[sevenperforce]

On 4/6/2019 at 5:33 PM, Laie said:

It's all quiet.... before the storm?

I don't want to show my hand just yet, or make a lot of noise about unlaid eggs, but as a quick heads-up: I'm on it, at the stage where the orbital assembly kit has been designed and I "only" need to fly the mission. So still several days, I guess, and only if I don't have to go back to the drawing board.

Anyone else doing this?

Looking forward to the submission!

On 4/6/2019 at 6:17 PM, bayesian_acolyte said:

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.

I always build most of my missions in reverse anyway.

[bayesian_acolyte]

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

 

 

[Laie]

Congratulations!

Using a double-decker plane is quite creative. Heck, using a plane at all is already creative enough in my opinion. I have an inkling that this won't be beaten.

[sevenperforce]

On 4/8/2019 at 8:35 PM, bayesian_acolyte said:

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.

Spectacular job! I checked your scoring and you are correct; my Don't Chute bonus says not to use any chutes, so having a vehicle with chutes onboard at launch is still okay as long as they aren't used as part of the mission. Accidentally bringing Jeb along is no big deal.....spectacular job having him ride a fairing base down from orbit.

I'll get that mission badge to you briefly.

[Laie]

On 4/2/2019 at 8:14 PM, sevenperforce said:

If your contingency lander has chutes, then you can program them to open at a particular altitude, stage them, then deorbit the lander with a piloted vehicle and let the contingency lander land itself.

As you wish: http://ksp.schnobs.de/Eve/E-salvo-deorbit.webm

[chargan]

Here's my submission. Nowhere near as light as the first entry but I'm pretty happy with it.

Heaviest payload at 11.982t. This should qualify for Birds of Prey, Home Sweet Home, Keiger Kounter, Express Service and Don't Chute.

(11.982)(0.95^2)(0.90^2)(0.85)=7.45t

https://imgur.com/a/nQPBQKU

 

[Laie]

The Department of Over-Engineering Proudly Presents: Untitled Space Craft

Mission as flown:

1. Refinery and Asteroid puller (two launches) snatch an asteroid as it enters Kerbin SOI.
2. Asteroid is parked in a highly elliptical 47° orbit, AP halfway between Mun & Minmus. Won't encounter the Mun because inclination.
3. Asteroid puller moves to LKO, assembly starts:
   • two launch platforms, various odds and ends
   • one Eve lifter
4. crew returns to Kerbin for a long lunch break until the transfer window comes up.
5. crew comes back on the last launch, assembly is finished.
6. vessel proceeds to asteroid for refueling (took under 6 hours)
7. Eve transfer, capture, (near) circularisation into a 90x200km orbit
8. piloted unmanned landing:
   • lander is provided with a carefully measured amount of fuel
   • Jeb points it retrograde, turns on the ignition, and jumps out of the vessel
   • all those wing pieces provide enough stability for reentry
     (90 second video of de-orbit, entry and splashdown)
9. manned landing:
   • Thrusters, RCS, airbrakes are used to land close to the first vessel
   • <300m is still a 5-minute swim
10. two launches with two people each, docking, return to Kerbin.
11. overshooting KSC proper but still landing on the premises.

(Note the spent launch platform in the background.)

Payload masses: between 17383 and 15983 kg

Qualifiers: Tilt-a-Whirl, Homes Sweet Home (both landings), Beach Bum, Keiger Kounter, Room to Move, Pro Pilot, Express Service, Water Park, Contingency. Are Beach Bum and Water Park cumulative, by the way? If yes, that would resolve to 6693kg.

At this point I'm pretty worn out and can't be bothered with making a proper web gallery. Please take a zip file holding lots of screenshots -- trying it myself, cycling through full-sized pictures seems to even work better than a gallery does.

 

[sevenperforce]

Wonderfully fantastic submissions! I'll get to scoring and those badges -- was out over the weekend.