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The Direct Ascent Challenge!


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Direct ascent is a method of landing a spacecraft on the Moon or another planet directly, without first assembling the vehicle in Earth orbit, or carrying a separate landing vehicle into orbit around the target body. It was proposed as the first method to achieve a manned lunar landing in the United States Apollo program, but was rejected because it would have required developing a prohibitively large launch vehicle.


Hmm... sounds perfect for a Kerbal-sized universe!

If you've been playing KSP for very long, you've almost certainly completed a direct ascent mission already, perhaps without even realizing it. Most people's first Mun/Minmus landing are direct ascents, unless they're specifically looking to recreate the Apollo architecture that actually flew. That's because it makes a lot more sense when the scales are so much smaller. But what if the player's mission is more dV intensive, or requires multiple landings? Even in our pocket solar system, Apollo-style architecture (Lunar Orbit Rendezvous) and even LKO assembly (Earth Orbit Rendezvous) are often used. What if the player chose to pursue more challenging missions using their earliest design ideology- direct ascent?

This challenge dares you to answer that question! Simply put, land on as many bodies as you can with a single stack- decouple only when you're done with a stage- no docking! The formal rules are below:

RULES:

1. No cheating during the actual mission. Cheating during testing is fine, but you should not be using F12, Hyperedit, or any abusive mods during the mission showcased in your screenshots. 

2. Part clipping should generally be kept to a minimum. Do not clip in ways that don't make sense. Girders inside girders is fine. A fuel tank inside an engine inside a fairing is not. If you're not sure, ask BEFORE you start!

3. You get 1 launch. Reverts/quicksaves are fine.

4. Do not interact with a stage after you have separated from it in any meaningful way. Don't dock to it, don't catch it in some bizarre girder mitt and have it push you, anything like that. This is the crux of the challenge- one single stack. (Radial components and decouplers are fine)

5. You should have at least 1 decoupling event between landings. Don't have 1 lander land on 3 different planets, even if it could. Think of it as landers on top of landers. Don't make fake stages just to satisfy this rule.

6. The Kerbals must be able to walk around on the surface (ie plant a flag) once landed anywhere. Wouldn't be much of a landing if you couldn't get out and kick some dust around!

7. Your difficulty should be on Normal or harder.

8. You need to return all Kerbals you launch on the mission safely back to Kerbin in the rocket they launched in.

9. The vehicle should have at exactly 1 Kerbal on board at all times except when landed on a planet. 

10. No ISRU.

11. I'm keeping this a stock challenge for now. Both DLCs allowed. Any mods which don't affect the mission are allowed. If you've got a mod in mind that you really want to use let me know and I'll check it out.

 

SCORING:

Scoring is based on the following chart. Simply sum the points from every body you successfully land and return from. Points are very roughly based on dV requirements.

Spoiler
PLANET POINTS
Moho 100
Eve 210
Gilly 36
Kerbin 0
Mun 36
Minmus 24
Duna 66
Ike 42
Dres 75
Jool* 400
Laythe 120
Vall 80
Tylo 150
Bop 70
Pol 66
Eeloo 90

*A Jool "landing" is defined as reaching an altitude of 0 or below in Jool's atmosphere. If you complete this task as well as landing on all 5 of Jool's Moons I will design a personalized badge with your name on it just for you to show off.

Your score is out of 1165 (a Grand Tour minus Jool). Highest point value mission wins.

 

SUBMISSION GUIDELINES:

Your submission should either be in the form of a series of screenshots showing significant events during the mission (staging, trajectory planning, landings, etc) or an edited video of the mission. Please keep video submissions under 15 minutes unless absolutely necessary (if you're going to more than 4 or 5 bodies, longer videos are fine). Your resources menu (fuel, EC, etc) should be visible at all important moments. You should also include a picture of your craft in the VAB with dV/TWR stats showing, either via stock or a mod's (KER/MechJeb's) windows. Craft files are welcome but not required. Screenshots should have captions describing what's going on, videos should ideally have annotations or voice overs.

 

You can grab this nifty badge to put in your signature:

QV8c0Bg.png

Here's my submission so you can get an idea of how this works: https://imgur.com/a/hBuTB2O

Mun and Minmus so 36+24= 60/1165 or about .05. Shouldn't be too hard to beat!

LEADERBOARD

1. cantab- 265 link

2. Martian Emigrant- 36 link

Edited by Jodo42
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"Grand tour minus Jool"

[Jool Lander intensifies]

 

But anyway, some clarifications are needed.

 

One: can I detach a lander and then have it fly back to Kerbin without rendezvous with my mothership? I.E. do the Jool fi- six by splitting my craft into a MIRV of six independent direct ascent vehicles. I.e. is parallel rather than serial direct ascent fine?

Two: what if the entire purpose of some "stage" is to have it trapped in a cage while it pushes you, but it never leaves and comes back? I.E. stock props.

Three: is Making History allowed? (For five meter parts)

Four: is Breaking Ground allowed? (For robotics without decoupling and inviting the Kraken).

Edited by Pds314
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1 hour ago, Pds314 said:

"Grand tour minus Jool"

[Jool Lander intensifies]

 

But anyway, some clarifications are needed.

 

One: can I detach a lander and then have it fly back to Kerbin without rendezvous with my mothership? I.E. do the Jool fi- six by splitting my craft into a MIRV of six independent direct ascent vehicles. I.e. is parallel rather than serial direct ascent fine?

Two: what if the entire purpose of some "stage" is to have it trapped in a cage while it pushes you, but it never leaves and comes back? I.E. stock props.

Three: is Making History allowed? (For five meter parts)

Four: is Breaking Ground allowed? (For robotics without decoupling and inviting the Kraken).

One: Definitely not. It must be in series. Sorry for not making this clear but that's basically the whole idea of the challenge, you have to carry all of your landers with you wherever you go (making it hard to go very many places without heavily optimizing each stage). If you're planning a Jool 5 and your first landing is on Tylo then the upper stages of your Tylo lander need to be your Laythe, Vall, Bop and Poll landers (and any transfer stages you need).

Two: Stock props are fine, and, along with Breaking Ground rotors, are strongly encouraged for anyone attempting a Jool "landing."

I know this isn't what you were intending but I also wanted to point out that "fake" stages that exist solely to satisfy Rule 5 or are otherwise in bad spirit are not allowed. An example of this would be an Ion lander that someone would take to Gilly, Bop and Pol that has 3 stack separators attached to cubic octagonals radially attached, that are staged right before each landing- ie the only thing that's changing before each landing is that 1 stack separator is being removed from the craft and nothing else. Don't do that. Decoupling events need to change how the ship operates in some meaningful way. I realize that's ambiguous but hope people get the basic idea; if not just ask.

Three and Four: Yes, I should have clarified. Especially since I'm using them in my own submission :sticktongue:

 

I should also clarify that just a Jool "landing" won't earn anyone a badge. That was an oversight on my part, especially now that helicopters are more feasible. If I thought a Grand Tour + Jool was possible in the serialized, no ISRU nature of this challenge, I'd probably award the badge for that. But I don't think it so, so a Jool Six would be fine for the custom badge. Will update the OP. If somebody does a Grand Tour + Jool in the serial style... who knows. I'll make a donation of $100 to the charity of their choice.

Edited by Jodo42
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Well, not even one landing in and my attempt is going wrong thanks to delta-V miscalculation, d'oh. I guess that's what I get for making my first stop Dres. I've resorted to looting the second lander's fuel for the first lander.

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4 minutes ago, cantab said:

Well, not even one landing in and my attempt is going wrong thanks to delta-V miscalculation, d'oh. I guess that's what I get for making my first stop Dres. I've resorted to looting the second lander's fuel for the first lander.

You may find these "advanced" delta-V charts useful. They're ancient, so take the numbers with a grain of salt, especially the atmospheric ones, but for what it's worth, I found them to be quite accurate for my short Mun-Minmus mission. 

 

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Those are the ones I used... :/

EDIT: It may be the plane change that got me, those charts specifically state they ignore inclination, and the first Dres window of a new save seems kinda lousy.

Edited by cantab
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To be Brutally honest...i did up to 216 Points (Vall, Bop & Pol), though only Asparagus Staging was used, but at least one Decoupling between Landings...yes, looks like i have to do a whole Jool 5 in Direct Ascent...I've been planning such thing for so long...

Edited by GRS
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I was doing a similar direct assent rocket a while back and did some math that may come in handy here. It turns out you can calculate which engine is most efficient for a particular TWR range on staged and asparagus rockets. So I did! The results will hopefully help save some time on the guesswork and dialing-in for the megarockets required for this launch.

 

In the charts below, Dawn is in blue, NERV is in green and Wolfhound is in orange. The line for a staged rocket is the brightly colored one, and the fainter lines coming off of it are for asparagus rockets. The closest faint line is for 2 stages burning simultaneously, then after that is for 5 stages burning simultaneously (most of my mega-rockets were like this), and finally is the mathematical limit of infinite asparagus. To use the chart, pick your TWR on the bottom axis and then look up. The higher the line, the more efficient the engine at this TWR in its most mass optimal configuration. The effective Isp can also be used for the following handy equation for planning purposes:  DeltaV = Effective Isp * ln(mpayload/mfullrocket), which can be used on any stage or set of stages using the same approximate configuration.

sHlBmDQ.png

In order to get the most mass-optimal configuration, you need to choose the optimal deltaV per stage. These values are shown below. Note that you don't lose much efficiency by being off a few percent, and it's typically better to go a little high in deltaV rather than a little low. Being off by 8+% is where the efficiency really starts to tail off.

e23FPGo.png   Huc9mHJ.png

Alright, best of luck with those megarockets!

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Impressively scientific!

Compared to your stated optimums, some of my Nerv stages were rather longer. Conversely my ion stage was much shorter, but it couldn't have been significantly longer in my mission.

Just landed Jeb safely back on Kerbin and never want to see another ion engine again. I had him bail out a few hundred metres up and use the personal chute because the capsule was coming down on a mountainside, hope that's OK.

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1 hour ago, cantab said:

Impressively scientific!

Compared to your stated optimums, some of my Nerv stages were rather longer. Conversely my ion stage was much shorter, but it couldn't have been significantly longer in my mission.

Just landed Jeb safely back on Kerbin and never want to see another ion engine again. I had him bail out a few hundred metres up and use the personal chute because the capsule was coming down on a mountainside, hope that's OK.

If it's good enough for Gagarin it's good enough for me! I look forward to seeing submissions soon.

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Hi.
 
This is my submission. (Mission haha funny)
 
19.3 KiloRoots, 34.5 Tonnes, 46 parts, vanilla.
 
0hNK47g.png
 
Departure

o0A1lwZ.png

Spoiler

Boosters separation

soUDDc1.png
 
First stage spent
Y6auaze.png
 
Orbit
R56aUKv.pngkMoIaMh.png

leaving Kerbin

ci1dFiN.png

Spoiler

Second stage spent

nd8yZsU.png
 
Munar stage finalizing Mun encounter
fPQR2Nb.pngNcMCzaz.png
 

Orbiting the Mun

PIoU3Kg.png

 

Spoiler

Going down

Xvy0kzf.png
 
Nearly there
DUnaB6f.png
 
Jeb working on the surface
4SuUSqp.png
 
And going home
iD155eM.png
 
Spoiler

Mun departure

09XvTGI.png
 
 

Return trajectory plotted

3VwF68S.png

Spoiler

Kerbin arrival

tUhx7J4.pnglPzggXR.png

 

All done

GosqyqH.png
 
Thanks,
 
 
ME

 

 
Edited by Martian Emigrant
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16 minutes ago, Martian Emigrant said:
Hi.
This is my submission. (Mission haha funny)
19.3 KiloRoots, 34.5 Tonnes, 46 parts, vanilla.
0hNK47g.png
Thanks,
ME

 

 

Beautiful rocket and especially lander. You didn't have your resources tab open but the rocket is pretty clearly legit. For just a Mun landing you get 36 points. Welcome to the leaderboard!

Edited by Jodo42
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1 hour ago, Jodo42 said:

Beautiful rocket and especially lander. You didn't have your resources tab open but the rocket is pretty clearly legit. For just a Mun landing you get 36 points. Welcome to the leaderboard!

Thank you.

The pole position won't last long.

 

There are points?

I am unclear on how to score over 400 points. if one wants Mun and minmus (36+24)=60.

  • Does one do two missions (IDTS)
  • one mission with two un-reusable landers (IDTS)
  • one mission with the same landers (IDTS)
  • one mission with the same landing whole ship (Ay caramba for the grand tour)

 

ME

 

 

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16 minutes ago, Martian Emigrant said:

Thank you.

The pole position won't last long.

 

There are points?

I am unclear on how to score over 400 points. if one wants Mun and minmus (36+24)=60.

  • Does one do two missions (IDTS)
  • one mission with two un-reusable landers (IDTS)
  • one mission with the same landers (IDTS)
  • one mission with the same landing whole ship (Ay caramba for the grand tour)

 

ME

 

 

If you look at the "scoring" section of the original post, there's a spoiler you can click that has a table that has all the point values for the planets and moons. Your goal is to land on as many planets/moons in 1 mission as possible. Right below the badge I have an example mission showing a Mun+Minmus mission. The Mun lander carries the Minmus lander down with it since the landings are supposed to be done in series.

Another example might be a Duna+Ike mission. The Duna lander would have the Ike lander as its upper stage, and the Ike lander would stay attached to the Duna lander during the Duna landing. Once you were done with the Duna landing stage (leave it on Duna or take off with it to burn up remaining fuel), you decouple the Ike lander and fly it to Ike and then home. If you wanted to do 3 landings, then when you landed on the first planet/moon in your trip, that lander would have to carry the 2 later landers down with it as well. And so forth. I hope that answers your question. A grand tour would indeed be extremely difficult, but there's a lot of ways to get more than 400 points, though they're all quite challenging.

Edited by Jodo42
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On 7/3/2019 at 1:29 PM, cantab said:

Impressively scientific!

Compared to your stated optimums, some of my Nerv stages were rather longer. Conversely my ion stage was much shorter, but it couldn't have been significantly longer in my mission.

Thanks! Yeah, despite where the mathematical optimum may be there's normally mission requirements like landing that are more important for deciding what the rocket looks like. I guess managing the tradeoffs is what makes design a good challenge!

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On 6/26/2019 at 3:31 AM, Jodo42 said:

RULES:

1. No cheating during the actual mission. Cheating during testing is fine, but you should not be using F12, Hyperedit, or any abusive mods during the mission showcased in your screenshots. 

2. Part clipping should generally be kept to a minimum. Do not clip in ways that don't make sense. Girders inside girders is fine. A fuel tank inside an engine inside a fairing is not. If you're not sure, ask BEFORE you start!

3. You get 1 launch. Reverts/quicksaves are fine.

4. Do not interact with a stage after you have separated from it in any meaningful way. Don't dock to it, don't catch it in some bizarre girder mitt and have it push you, anything like that. This is the crux of the challenge- one single stack. (Radial components and decouplers are fine)

5. You should have at least 1 decoupling event between landings. Don't have 1 lander land on 3 different planets, even if it could. Think of it as landers on top of landers. Don't make fake stages just to satisfy this rule.

6. The Kerbals must be able to walk around on the surface (ie plant a flag) once landed anywhere. Wouldn't be much of a landing if you couldn't get out and kick some dust around!

7. Your difficulty should be on Normal or harder.

8. You need to return all Kerbals you launch on the mission safely back to Kerbin in the rocket they launched in.

9. The vehicle should have at exactly 1 Kerbal on board at all times except when landed on a planet. 

10. No ISRU.

11. I'm keeping this a stock challenge for now. Both DLCs allowed. Any mods which don't affect the mission are allowed. If you've got a mod in mind that you really want to use let me know and I'll check it out.

Which means :

  • Do we need 1 lander-ascender per planet / moon?
  • Are part mods and MechJeb allowed?
  • Are (Multiple) shuttles allowed?
  • Are docking to mothership to transfer crews to another lander allowed?
  • Does a staging event must be done prior to reentry back to Kerbin?
  • Must contestants land on other planets? (i.e Does submissions eith Mun and Minmus landings accepted?)
  • Does a submission with a planetary base-landing (With no functional ISRU involved during the mission but used outside the mission) and a separate Lander-Ascender combo accepted? (i.e You land a base then land a separate single-stage lander-ascender next to the base then bring the Kerbals from the base to the 'lander' for ascent)
Edited by FahmiRBLXian
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14 hours ago, FahmiRBLXian said:

Which means :

  • Do we need 1 lander-ascender per planet / moon?
  • Are part mods and MechJeb allowed?
  • Are (Multiple) shuttles allowed?
  • Are docking to mothership to transfer crews to another lander allowed?
  • Does a staging event must be done prior to reentry back to Kerbin?
  • Must contestants land on other planets? (i.e Does submissions eith Mun and Minmus landings accepted?)
  • Does a submission with a planetary base-landing (With no functional ISRU involved during the mission but used outside the mission) and a separate Lander-Ascender combo accepted? (i.e You land a base then land a separate single-stage lander-ascender next to the base then bring the Kerbals from the base to the 'lander' for ascent)

There needs to be at least 1 stage per planet/moon. You need to land the entire mothership whenver you land somewhere. Once a stage of the mothership is empty you can decouple it.

If you have a mod in mind let me know, but the challenge is intended for Stock+DLC's only, in terms of engines/capsules/etc. Mechjeb is fine.

You get 1 launch. No shuttles.

If you could show me what you mean by this it would be helpful, but the answer is probably no.

No.

No. My submission (which you can see under the badge) only went to Mun and Minmus. Martian Emigrant only went to the Mun. 

No, because of Rule 9.

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Mission album up. Since the mission called for a lone Kerbal, I decided to go to the lone bodies of the solar system, so Dres, Eeloo, and Moho in that order for 265.

Complete album: https://flic.kr/s/aHsmERJt81

Brief summary of stages:

Stage 8: Rhino core, two Twin Boar liquid boosters, ten Kickbacks. Liftoff to Kerbin orbit (and leftover fuel was used to begin our departure burn).

Stage 7: Drop Kickbacks.

Stage 6: Drop liquid boosters.

Stage 5: Jettison fairing.

Stage 4: Six Nervs. Kerbin departure to Dres landing.

Stage 3: Three Nervs. Dres takeoff to Eeloo takeoff.

Stage 2. Seven ions. Eeloo departure to begin Moho capture.

Stage 1. One Nerv. Finish Moho capture to Moho departure.

Stage 0. Decouple orbital parts and arm chutes for Kerbin re-entry.

Trajectories and landings:

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52 minutes ago, cantab said:

Mission album up. Since the mission called for a lone Kerbal, I decided to go to the lone bodies of the solar system, so Dres, Eeloo, and Moho in that order for 265.

Complete album: https://flic.kr/s/aHsmERJt81

Brief summary of stages:

Stage 8: Rhino core, two Twin Boar liquid boosters, ten Kickbacks. Liftoff to Kerbin orbit (and leftover fuel was used to begin our departure burn).

Stage 7: Drop Kickbacks.

Stage 6: Drop liquid boosters.

Stage 5: Jettison fairing.

Stage 4: Six Nervs. Kerbin departure to Dres landing.

Stage 3: Three Nervs. Dres takeoff to Eeloo takeoff.

Stage 2. Seven ions. Eeloo departure to begin Moho capture.

Stage 1. One Nerv. Finish Moho capture to Moho departure.

Stage 0. Decouple orbital parts and arm chutes for Kerbin re-entry.

Trajectories and landings:

 

  Reveal hidden contents

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It seems like every time I complete some big mission, the landing on Kerbin is always in some extremely mountainous region, threatening to destroy my pod in what should be the easiest part of the mission. I guess the curse struck you this time instead of me!

 

Epic mission. I really hate going to those 3 bodies in particular- I don't like small gravity wells and high inclination- and I can't imagine going to all 3 even without direct ascent. I did a Dres landing recently and it was a huge pain to get it down safely because it was so top heavy; my lander was probably half the height of yours!

 

This is pretty much a textbook mission according to my vision for this challenge. I was getting worried because so many people were asking exactly what the rules meant and there were so few submissions, so I'm very glad you got it figured out so well. For anyone who's unclear on how your mission should be set up, please reference this post. One big lander whose upper stages sequentially transfer to, land on, and re-orbit other planets. Congrats cantab for 265 points! That puts you at the top of the leaderboard. You really earned the badge! (if you chose to use it :)

Edited by Jodo42
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Jool 5 Direct Ascent...Hmm...I WAS Thinking of that real Seriously, except No Chairs, which seems to end up increasing Difficulty a lot, i can say, Delta v required = 22k, Landing big stuff on Tylo is something I'm willing to avoid for reasons, Good job @dnbattley, you raised my Fighting Spirit, I will do that, Though Capsules will surely make things harder for reasons...will be my 4th Jool 5, that follow the Jool 5 rules.

Edited by GRS
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