The KSP Caveman Challenge 1.3.x - 1.10.x [re-booted]

[Muetdhiver]

Well, here we go. Vanilla & removed making history stuff.

This is going to be fun and interesting. I toyed a bit with a sandbox save to experiment with builds, and I found that in theory one can do minmus orbit with pure tier 3 tech.

Anyway. Diamond attempt from the get go. We'll see how that pans out.

Spoiler

This is how we roll. It's going to be quite a fun endavour. First, contracts for advance money, complete the science one so that  we can launch. Easy flight, with a shore landing, which is cute for the science and the spashdown.

With a few goo and EVA's at the runway and pad, we get the thermometer, and do the Oh so classical KSP science roller. This nets enough science for the basic rocketry. A big pile of rocks gets jeb to 100+ km. Breached the atmosphere and collected good science.

After that, a parachute contract for easy monies, and start designing an orbital rocket. Something simple using the bottom coupler trick to fake side couplers is always a good way to go. I also thinking about mun/minmus flyby's on low tech, and I got a pure tier 3 idea that should pack close to 5K DV. Will need some sandbox testing for stability and stuff though.

 

[Muetdhiver]

Second part : Orbit, Ladder ride & Red boulder project.

The next step is obviously orbit and recovers with their associated missions. Here is the summary, pics in the spoiler part.

 

I start with a simple orbital rocket with the truster hammer / swivel combo. Nothing fancy, mission goes like a charm. Banks is just shy of 30K and I get the reliant, which enables a lot of stuff.

Spoiler

After getting to orbit, I do a high altitude sounding rocket for more science, and then.... Since I never did it before, I decided to start with Bill riding the ladder to polar orbit. Good science, but after orbit we are short on fuel for the retro-burn, so bill has to push the re-entry module a bit. A classic manoeuvre. Because I never did it before, I did some sandbox testing and flying till I nailed the ascent profile to not loose or cook Bill en route

Spoiler

Toasty ascent, but now Bill can chill out in orbit

Bill pushing it back in the atmosphere

For the next step, I decided to do something that I haven't seen done before : duna on reliant tech only. The rocket and transfer is being tested in a sandbox save because eyeballing duna transfers is a new thing to me. The delta-V for the rocket is a bit above 5K, but has truely atrocious aerodynamics

Edited May 10, 2018 by Muetdhiver

[Muetdhiver]

Third Part : Red boulder and Mun.

My next step is Duna using a reliant only rocket. The core idea is a minmal core stack with massive side tanks that are dropped bits by bits during the ascent. The DV in the sandbox is about 5.3K dv for the stack, but the side tanks have horrible drag, making the kerbin orbit much more costly than 3.4K. In fact it shoots up to 3.9-4.1K, leaving about 1.3K for the Duna trip, which means not much room for correction manoeuvres, and also implies aerocapture for orbit.

I had to test the rocket a few time in the sandbox to see how to best get it to space with as much DV left as possible and check the DV budget when flying with no node (but patched conics). I do a few last check in a sandbox w.o patched conics to learn how to deal with the final duna approach. I find that you simply need to get the orbits crossing at half the distance when duna catches up. Don't get it wrong it's not easy and at this stage it feels iffy. Still, I go ahead and launch.

Spoiler

Red boulder ascending. So far, so good.

Orbit with close to 50Lox remaining, and AP 200+km in the right direction. So far, so good. Jeb is feeling okay about this.

Getting close to duna, after a small correction burn mid way. Tricky part is now.

Using criss-crossing orbit a mid point and radial burns, AP at 2000Km. Good, because the fuel tanks are getting really empty. Running on fumes. Ap lowered to 26km on a polar orbit.

In orbit after sucessfull capture and a few aerobraking to lower AP. We could land but I opt not too. For now. PE is left just in atmosphere to allow further lowering of the AP.

The Duna mission gives us minimal science (no transmission, nor return on this tech level), but good credits from world firsts. Now, same rocket with a tad of tweaking will make short work of MUN.

Spoiler

Ascent is easy now, LT-100's instead of LT-200's on the last side tank part for a but of extra DV, that get eaten by the goo. Burn worked well, but direct impact trajectory. Correction burn, then Aerobraking in multiple steps for a safe landing.

Valentina is very happy about the drag now

Mun provides a Science & Credit bonzana, allowing to unlock the terrier node. Now, we can really start working, and things should get easier ?

Spoiler

 

Edited May 11, 2018 by Muetdhiver

[Mr. Peabody]

@Muetdhiver, most impressive! I wasn't even aware Duna was a plausible target with reliant tech. Keep up the good work!

[Muetdhiver]

Fourth part : Mojito Explorer.

Now that I have access to the fancy terrier 909, I can improve the red boulder design to reach much higher delta-V. Estimations are in the 2.2 to 2.3K DV once in orbit. Enough for a duna return trip or a minmus landing. Since this is a new design, but rather similar in concept to the previous one, so I only do on dry run in the sandbox and then go to minmus. Easy as cake. Orbit is done directly to the minmus inclination using the mk1 eyeball.

Spoiler

The brand new "Mojito Explorer" ready to go. Same design as the "Red boulder", only with aero caps, and top mounted drop tanks for the terrier. the service bay does it all : heatshield, science gear protection and aerobrake in a 0.1T package of awsomeness. First time I notice how good that part is.

neatly in orbit with ~2.2K DV left. Gorgeous.

Plenty of credits, and after a second two-biome minmus landing, enough science for the science jr, and enough for electrics or Propulsion systems. We also have a nice Duna exploration contract to fullfill. Decisions...

[Muetdhiver]

Fifth part : Bloody Mary Explorer.

After burning some cash by crashing a rocket filled with science Jr due to an epic fubar, I decide to go back to regular piloted rockets. A duna rocket is built from the Mojito Exlporer frame. Essentially the same save for : science box makes thermometers and barometers reusable, and the goo are mounted on the exterior. Why ? Simply but, I plan to use the well know method of aerodecoupling during the aerocapture. Boffin's calculations with the abbacus show a gain of 70 m/s of DV if the 150kg of goo are "detached" after use. Ejection angle and timing are approximatly known from the trusted method of using an angle ruler on top of the screen. DV calculation with mass ratios and ISP show 2050m/s in LKO, which is good. Burn goes smothly, and as I computed a DV table to follow the tank gauge, this time the LKO ejection burn is close to perfect (minmal waste in kerbol orbit correction burns).

Then... looking at the AP of my orbit, it seems not far enough for a good encounter. But I'm really not sure, and I decide to do a save backup because it could go very wrong. And it does. I got a 24'000 km duna encounter, which I can correct, at the price of no return. Simply put the orbit crossing point was too close, and I missed. Given the budget, I cannot correct more than 10'000 km. So I did the sensible thing and did a rollback. Yeah, that really sucks. I do a 5m/s prograde correction burn to push the crossing back. Goes like a charm. Most likely : slighty wrong angle at ejection. Much painfull.

Spoiler

57 LFO left. I need a bit less than 45 to return. A bit less if I can "decouple" the goo.

Encounter with a single save scum. That was bad, but Oh well...

Tasty science, still 54 LFO left after the final corrections. Good science ^^

"Aerodecoupling" of the goo. About 16km. Toasty but not too much. Science in atmosphere done too

Now we just have to get Valentina back. Hopefully without messing the ejection up this time...

Edited May 13, 2018 by Muetdhiver

[Muetdhiver]

Sixth Part : Duna Landing

Exploration society wants us to go there. This will require a much larger ship, docking in space and so on. Nothing too hard. The duna transfer is pretty much nailed, only thing is... Valentina only did easy landings, and we don't have the landing leg tech. So, in order to do the prep work for duna, starting with a classical mun landing souds like a good plan.

Spoiler

The Mun vessel ready to go.

Mun low orbit, so far so good. Fuel looks good. I plan to land on the terrier. Should not be too hard.

Turns out, the terrier just had enough fuel, and I nearly tiped over. Quick reflexes and SAS saved me, but it was closed since I disabled the fuel in the tank for the previous staging. The spark held up the impact and Valentina does not tip. Close call for our last Pilot. Re-Enable the fuel, which will give 1.7K dv. More than enough.

The mission was a near disaster, but the science is yummy. I decide to do a quick minmus science expedition with science Jr. Very tasty, but very costly those... funds are starting to run low again... time to go back to duna. The vessel is an mashup of the minmus science vessel and the mun one. It should have more than enough DV (800 spare at least).

Spoiler

The Bloody Mary Explorer vessel assembled.

Ejection burn goes well, calculation are mostly correct, but the Duna intercept is pretty bad, at 21000 km. Lots of wasted fuel but we should have enough. Science Jr's are used high, low and in upper atmosphere. The 26km capture goes okay, a little burn to be sure to not escape. However, before the second aerobraking pass I get a Ike (damn piece of space rubble) encounter that kicks the Pe to 1900 km and the Pa to the limit of duna SOI. More science, but more fuel wasted. It starts to look a bit grim. 30km final capture with the idea of landing as close as possible to Duna's equator.

Spoiler

Bad

Bad, bad encounter.

The well know disruptive rock. We better not cross its SOI on our way back home.

Lowering Pe for landing...

It's at this point that I reallize that while I packed two chutes for duna, I did not plan for the Kerbin landing XD. So used to repacking them... well... we'll do a half powered landing.

Spoiler

Single chute ? No problem. Science is delicious around here.

Valentina sips a nice Bloody Mary watching the sunset and talking to Jeb a bit. 9 year around the red rock are taking a toll...

Easy take off

Kerbin intercept is not very pretty, and we are really on fumes by the end. Good thing we packed a lot of spare fuel...

It seems we are closing with the challenge...

Duna does provide quite a bit of science, and a truckload of credits, especially with the science from duna surface mission and the exploration society one. This mission was way too close. If I had not packed nearly a full FL-400 worth of spare fuel, it would have been night impossible. I still need 315 science, which is a lot ?

This can be farmed from mun and what remains of minmus, but that's going to be tedious. Also, I got spare cash. If I cock up, I can recover and with the OCTO's, even Bill can drive to Mun to finish the job. So, to finish the serie, I'll try an Eve aerocapture, science Jr low/high/upper atm and sampling the three biomes of Gilly. The RCS thrusters are unlocked Lessons have been learned, I will pack a lot of extra fuel. Maybe two tanks this time.

It should suffice. And the backup plan is farming with Bill, which is still recovering from the ladder ride...

Operation Deep Purple is green lit by the tribe.

 

Edited May 22, 2018 by Muetdhiver

[Mr. Peabody]

16 hours ago, Muetdhiver said:

Sixth Part : Duna Landing

Most impressive! You're well on your way to becoming the first Caveman to complete diamond as their first attempt at the challenge. You are also the first Caveman to land on and return from Duna. I'll be looking forward to seeing the results of your Eve mission.

For your successful Duna land and return mission, I am honored to award you the "Order of the Trilobite."  You may claim your badge. 

 

[Muetdhiver]

I did not realize that a Duna landing had not been done before. Glad to do a first

I'll wear that Trilobite badge proudly.

As for the Eve mission : I did quite a lot of math on it, and it's going to be really tough. For a start, the fact that Eve has a non negligible orbital inclination difference w.r.t kerbin will complicate things. The risk of missing Eve completly is quite real, since correcting for the inclination at AN/DN will change AP/PE and so likely mess up the encounter badly. To make matter worse, doing a precise enough burn "caveman style" is fine for duna where the TWR is okay, but for my Eve/Gilly vessel, the burn will be 2-3 minutes long, i.e. a crapshot without manoeuvres. Sandbox testing shows that getting it right is going to be a lotery. Which means that I have to plan for failure, i.e. miss Eve, and correct the orbit to catch it on a later pass with near fractional periods. Which means (a lot) more fuel. Plus spare for the multiple cockups that will happen (if the duna landing is anything to go by). And then there is getting to Gilly...

So far the vessel is 11t with about 8t of fuel, but I might add an extra 2t of fuel for safety (be I'm getting in the seriously diminishing return region of the rocket equation, i.e. 2T extra for a bit under 300 m/s). I plan to pack at least 1300 m/s of spare fuel. I must say that those 3x science Jr's are quite a pain in term of dry mass (costing me about 530 m/s).

 

 

[Muetdhiver]

Part Seven : Eve capture.

I start with adding an extra 2T of fuel to the Deep Purple Explorer. That should ensure security. Also, I'm feeling iffy about aerocapture at Eve, as the vessel will go quite fast. Braking should be possible to some extent though. The bigger issue is getting there in the first place. The burn will be 3minute long. The ejection angle should be about 155° to retrograde. I do about 15° in 90s and so decide to start the burn at 170° to retrograde pointing 10° below prograde to account for the trajectory curvature. Not 15° below prograde since the orbit will openup with the burn. The burn is okay, 2-3° degrees off using the good old mk1 eyeball. So, no encounter most likely.

The vessel orbit PE has to be lowered a bit to reach eve orbit. By eye it's clear that an encounter will not happen. Valentina will miss it by days. It's fine, I planned for this. First step to remediate to the issue is change the inclination to be CoPlanar. Not an absolute necessity, but it will make things easier and allow for some amount of sloppyness. This finish draining the drop tank n°2. I measure how late we are with eve at our PE. 86 days... ouch, thats really not great. Or is it ? The vessel does it's orbit in 338 days (taking the departure date for the AP and using maths). We will gain back 76 days on each orbit. This means that after two more orbits, we'll be 238 days late on eve, or 34 days too early. I correct the orbit AP to be there on the right time, and go a fine correction on the second orbit, accounting for hours and minutes (you have to). Spreadsheets for the win.

And there we are, after about three years :

Spoiler

The Deep Purple Explorer at ejection burn

Orbit after CoPlanar correction and first AP correction to catch up Eve

After second AP correction at PE to account for hours and minutes. Encounter is really nice (IMO) for such a crude technique.

Inclination correction to exit on Gilly's plane. PE set at 84 kilometers. I'll burn to finish the capture, rather than risk losing the vessel. I realize that I should have put a service bay behind the sacrificial science Jr's to act as thermal shield. next time maybe.

Science !

Heat, and more science before things explode. Small capture burn after that.

There we are, finally in Eve orbit with the right inclination for Gilly !

Edited May 26, 2018 by Muetdhiver

[ManEatingApe]

1 hour ago, Muetdhiver said:

There we are, finally in Eve orbit with the right inclination for Gilly !

Great work, most people would be content with 1 inter-planetary mission!

Jool next? 

[Mr. Peabody]

7 hours ago, Muetdhiver said:

There we are, finally in Eve orbit with the right inclination for Gilly !

Most impressive! 

[Muetdhiver]

Part 8 : Gilly and delicious greenolith

After getting into eve orbit, I use the remaining fuel from the third tank to get a gilly encounter. The science Jr's and empty tanks are dropped, and we start using fuel from tank number two for Gilly orbit. This tank is parked into Gilly orbit while the RCS equiped part of the Exploration vessel goes to the surface for a bit of biome farming. I get lucky and locate the Greenolith. I get the precision engineering tech, which is nice but not overly usefull.

Spoiler

Catching the elusive Gilly.

Into Gilly's orbit, parking the return fuel.

How fortunate ^^ So much money.

Landing on the Greenolith, delicious science from Gilly's surface. So easy to move around with RCS, it's quite a lot of fun (never done before).

 

After collecting all the science, I prepare for the return by circularizing at 55'000 km above Eve. Burn is done with angle ruler and fingers crossed. I'm quite sure I'll have to do several orbits around Kerbol to get back home. And... In the end it takes three years with four orbits. First correction is completly wrong due to a misscalculation, but corrections #2 and #3 are done much better and allow to compensate for the initial mistakes. The kerbin encounter is at 4000 km PE, which is beautifull for such a method. 800 m/s of DV left upon re-entry. Correcting over several kerbol orbit is much more fuel efficient than correcting with massive burns near the encounter point using the eyeball. Slower, but who cares... aside from Valentina that aged 10 years on this mission.

Spoiler

Vessel orbit after last corection burn. The probe is the last drop tank ditched after correction burn #1 and planar change.

Look at this. 4192km, using caveman tech and basic maths. Really cool

Done. All T5 nodes unlocked, a lot of credits and enough science left for a T6 node. Challenge complete I guess.

And there we are : Valentina is back home. Jeb is still enjoying the view near Duna, and all T5 nodes are done. It was tough, fun and very instructive. To note : I failed my first two tries at diamond by running out of money before the terrier. Once the terrier is there, things are mostly "done" in the sense that one can access to loads of science and credits with Mun and Minmus.

Going interplanetary is much more fun than Minmus/Mun strip mining IMO. Duna is quite doable with eye, rulers and simple vessels. OTOH I don't think Eve can be reliably done with a direct encounter (Was not able to in the sandbox testings). My advice to anyone looking to do this is : Correcting the vessel orbit with small correction burns to adjust the orbital period is the safe and economical way of doing it.

Doing Jool is... tantalizing... Dangerous too. All those big moons are a big hazard without patched conics. It would be fun to get to Pol and Bop Greenoliths for T6 science nodes. Aerobraking in Jool with caveman tech is a fun thought XD

And the most "Caveman" rocket part is the 1.25 service bay... Thermal shield, aerobrake and protects your science, all for 0.1T

 

[Mr. Peabody]

6 hours ago, Muetdhiver said:

<snip>

Excellent run! I am honored to award you the the diamond level Caveman badge. Unga Bunga!  

Side note: I only now noticed that you had KER installed. That's forgivable this time because I didn't notice it sooner and I'm not a cruel monster. Next time though it is not an allowed mod.

One more thing, I can't update the leader board at the moment due to a forum glitch. I will do so as soon as possible. Thank you for your patience.

Edited May 28, 2018 by The Dunatian

[Muetdhiver]

Ker was used in the sandbox save because computing the rocket equation for each tests is a bit too crazy.

For the caveman save wet over dry and logs where used. 

The place where ker would really be an issue is in flight. It's as good as having patched comics as far as encounters go if you know the maths.

 

[Superfluous J]

24 minutes ago, Muetdhiver said:

Ker was used in the sandbox save because computing the rocket equation for each tests is a bit too crazy.

Circumventing the lack of KER (or any other mod) by building your ships in another save with those mods enabled is (or at least was) actually banned explicitly from the very first iteration of the challenge.

[Muetdhiver]

But sandboxing is fine right ?

Damn. I should have made a spreadsheet like for the transfers corrections to keep things clean.

Unrelated question : does anyone know how to do a somewhat accurate grav braking/assist caveman style ? It would help a lot for a jool mission.

 

[Mr. Peabody]

8 hours ago, Muetdhiver said:

But sandboxing is fine right ?

Damn. I should have made a spreadsheet like for the transfers corrections to keep things clean.

As stated earlier, it's forgivable due to my blunder in not spotting it earlier and because of the sheer difficulty of diamond level. In future avoid using KER or similar mods at all.  

Edited May 28, 2018 by The Dunatian

[Muetdhiver]

1 hour ago, The Dunatian said:

As stated earlier, it's forgivable due to my blunder in not spotting it earlier and because of the sheer difficulty of diamond level. In future avoid using KER or similar mods at all.  

I built a Ker spreadsheet and will make a "clean" Jool mission to make up for it.

I might try to use on pad assembly for the giggles.

[ManEatingApe]

1 hour ago, Muetdhiver said:

I built a Ker spreadsheet and will make a "clean" Jool mission to make up for it.

I'd love to see a Caveman/Jool-5 combo, as it would combine the 2 longest running most popular challenges.

(as well as being insanely difficult)

1 hour ago, Muetdhiver said:

I might try to use on pad assembly for the giggles.

Do it! It's a lot of fun, tweaking it just right...

...and it goes wrong very entertainingly 

[Muetdhiver]

By Jool5 you mean getting in each moons SOI or orbiting each moons or Landing on them ?

Landing is probably a no go (?). I mean, one would need a gaszillion DV on top of inefficient transfer burns.

Quick clarification : Are greenolith T6 techs allowed ?

[ManEatingApe]

16 minutes ago, Muetdhiver said:

By Jool5 you mean getting in each moons SOI or orbiting each moons or Landing on them ?

Landing. Additionaly rule 7 of the Jool-5 requires that your Kerbal can get out onto the surface and walk around.

This would require upgrading the Astronaut Complex, breaching the Caveman rules. However it would probably be an acceptable compromise to temporarily upgrade, screenshot the Kerbal on the surface and getting back into the capsule, then revert. 

16 minutes ago, Muetdhiver said:

Landing is probably a no go (?). I mean, one would need a gaszillion DV on top of inefficient transfer burns.

Yup, assembling a massive multi-docking port Kraken-bait monster craft both on the ground and in orbit would most likely be required.

16 minutes ago, Muetdhiver said:

Quick clarification : Are greenolith T6 techs allowed ?

@The Dunatian has the final call on this, but to me using any tech over level 5 would violate the Cave spirit.

 

Edited May 28, 2018 by ManEatingApe

[Mr. Peabody]

1 hour ago, Muetdhiver said:

Landing is probably a no go (?). I mean, one would need a gaszillion DV on top of inefficient transfer burns.

Quick clarification : Are greenolith T6 techs allowed ?

Landing is possible, but Tylo will be a killer. In answer to your question, I'm actually not sure. I haven't ever gotten T6 tech from a greenolith. Is the tech node you receive random or does it depend on the body you found the greenolith on?

[Muetdhiver]

AFAIK, there is one greenolith per body. They all give a random locked but accessible tech.

Actually, both Tylo and Laythe will be hard to crack and killers DV wise.

At the moment I'm considering restricting landing to Val / Pol /Bob and flybys / orbits for the others.

On pad assembly is a Kraken Den.

By first estimates a full jool5 with landings will need a vessel in the range of 150 to 200t in lko.

Big issues are the impossibility of fuel transfer, which means that every lander is single use and no crew transfer means that the cabin must stay the same. That makes for one 24t tylo lander, 3x6t landers for the four other bodies and an additional 6t return vessel. Adding 25t of fuel for jool system travelling, the payload will be about 75t. Adding in the ejection burn and tylo encounter / capture about 3.3K dv are needed. At 350 isp that will be about 11x or mass ratio close to 3. I.e. 200t+.

Can it be done with all the docking ports required ? Or will it be buggy as hell ?

 

Edited May 29, 2018 by Muetdhiver

[Mr. Peabody]

On 5/28/2018 at 4:22 PM, Muetdhiver said:

there is one greenolith per body. They all give a random locked but accessible tech.

I'm just going to allow all tech from green meanie monoliths. There is no way to control what nodes you end up with, so there is a good possibility that you could end up with a useless tech node. In addition, most green meanie monoliths are very difficult to even reach let alone locate with low tech probe cores. (A Caveman's best core, the Probodyne OKTO only has a 6% detection chance, the lowest of any core in the game) By far the easiest to get are the monoliths on Minmus and Gilly, because both moons are relatively small and have no other anomalies. Kerbin and the Mun's green meanie monoliths are extremely difficult to find because they are mixed in with many other anomalies and both celestial bodies are quite large. It's literally looking for a needle in a haystack trying to locate them with low-tech probe cores. That leaves only one "easily" accessible green monolith; the one on Minmus. All others either require a huge amount of effort to find or an inter-planetary transfer with no manuever nodes. If you can find it, go for it.

P.S. I triumphed over the forum glitch and managed to update the leader-board. 

Edited May 31, 2018 by The Dunatian