Caveman heavy lifter challenge

[GoSlash27]

 I was prepping for a caveman launch with some voltronning- in- orbit and the thought struck me: Just how much payload can be orbited in a single launch using caveman tech and limitations? I started this challenge to find the answer to that question.

Objective: Place the heaviest inert payload into LKO in a single launch and detach it. The payload may not assist in this and must have a periapsis of not less than 70 km. 

Restrictions: Caveman tech only, caveman restrictions, single launch.
-Caveman tech: Stock level 5 or below parts only.
-Caveman restrictions: 18t mass maximum at launch. 30 parts maximum. Vehicle dimensions may not exceed 20m x 20m x 21.2m. No action groups.
-Single launch: No voltronning launch vehicles or payloads.
-Inert payload: The payload must not assist in any way. It must not provide any thrust, fuel, guidance, electricity, or torque. When using a decoupler or shroud, it must be attached to the launcher. *EDIT* You may not transfer unused fuel from your booster into your payload once you leave the VAB.
-Additional: No cheats, no mods, nothing that violates the spirit of the challenge.

 

Here's my entry to get the ball rolling:

http://s52.photobucket.com/user/GoSlash27/slideshow/KSP/Caveman challenge/130Lifter

"RockChucker" 2.95t payload, 17.963t at launch.

I'm hoping somebody can break the 3t barrier. Gaarst was the first to break this.
Good luck!,
-Slashy

 

Leaderboard

1) Cunjo Carl   Huck                4.28t
2) Gaarst          ROcket 10       3.66t
3) GoSlash27  Gustav III         3.25t
4) Gaarst          ROcket 1         3.01t
5) GoSlash27   RockChucker 2.95t
6)
7)
8)
9)
10)

 

Edited March 3, 2018 by GoSlash27

[Human Person]

On 24.6.2017 at 3:34 PM, GoSlash27 said:

 

Edited June 25, 2017 by Physics Student

[Gaarst]

My attempt, using ROcket 1 because I forgot to name it in the first place:

Album link: https://imgur.com/a/Zi49A

All conditions are respected (I think). Brought 3.005t to LKO easily: I had about 100m/s of dV left in the tanks, did not flew in the most efficient way, lost a bit of dV due to low TWR (though a 10kg margin doesn't allow for much modifications on the launcher) and overshot my orbit by a bit ending in a 72x71km orbit. It probably could have put 3.015t to orbit, anymore and I would have needed to change the launcher because of the mass limit.

 

EDIT: used KER in the VAB to design the rocket.

Edited November 28, 2017 by Gaarst
Fixed album link

[GoSlash27]

1 hour ago, Physics Student said:

Why this restriction? In the challenge, you try to build the most efficient rocket you can. Having to detach your payload means having to specifically design your rocket to just so reach orbit. Most of the times -especially in the caveman challenge- that's not the most efficient way to go. Also, you normally want to go further than LKO.

Example: The Saturn 5. It wouldn't have had such a high payload to orbit if it had to be designed to just reach orbit and that's it. Using the 3rd stage to achieve LEO increased its overall payload to the moon.

Physics Student,

 These restrictions are in place in order to place the focus on the lifter rather than the payload. While I agree with everything you're saying in principle, in practice (for the purpose of this competition) it would blur the lines between payload and lifter and people would game it.

Best,
-Slashy

Gaarst,

 I like the 2 Thud approach Well done!
 Since your orbit screen shows 3.01t, I'll call that the payload. *edit* since you have so much leeway on ⌂V, I'm sure you could drain some fuel from your upper stage and add it to the payload tank. The upper stage won't care because it's pushing the same total mass, and total launch weight would remain the same.

Can we get 3.02?

Best,
-Slashy

Edited June 24, 2017 by GoSlash27

[Human Person]

I can't delete my own content, only edit it.

Edited June 25, 2017 by Physics Student

[GoSlash27]

Physics Student,

 3.38t is downright impressive! A couple problems: You can't have the shroud attached to the payload. I'll need you to resubmit the entry to correct that. Also, any guidance or electrical storage must be contained in the booster.

I'm sure you can still knock it out of the park with a regular nosecone. Containing the guidance in the booster is going to cut down your payload a bit...

Best,
-Slashy

 

Edited June 25, 2017 by GoSlash27

[Human Person]

I can't delete my own content, only edit it.

Edited June 25, 2017 by Physics Student

[GoSlash27]

http://s52.photobucket.com/user/GoSlash27/slideshow/KSP/Caveman challenge/130Lifter/GustavIII

I've managed to hit 3.2 tonnes with the Gustav III. I'm sure that record won't stand long...

Best,
-Slashy

[GoSlash27]

Physics Student,

 Sorry, you can't transfer your unused fuel into your payload and count it as payload. Your payload must be completely inert; weighs exactly the same in orbit as it did in the hangar.

 Best,
-Slashy

[Human Person]

I can't delete my own content, only edit it.

Edited June 25, 2017 by Physics Student

[GoSlash27]

Physics Student,

 Either you misunderstood my intent or I was unclear. I permitted him to adjust fuel in the VAB, not in orbit.

 When in doubt, simply remember this: the competition is about the lifter, not the payload. You may not utilize the payload to assist you in any way. 

And before you decide to try it, you may not edit your craft file either.

Best,

-Slashy

[Human Person]

I can't delete my own content, only edit it.

Edited June 25, 2017 by Physics Student

[Gaarst]

As @Physics Student noted earlier: TWR is important to fight gravity drag in the earlier stages of the attempt. I took my previous lifter, reinforced the lower stage, now powered by one Reliant and 4 Sparks (Vernier hype) instead of the dual Thuds, giving much higher TWR at launch. I modified the upper part accordingly, mostly optimisations and moving fuel from the stage to the payload, allowing me to have a smaller tank for the second stage, saving some more mass.

As a result of the TWR increase, the flight profile was much more aggressive, with a gravity turn starting a couple seconds after liftoff (hitting 45° around 8km). From there, I raised my apoapsis to 70km in several steps (always thrusting exactly prograde) to avoid overshooting it to end up in a 70x40km orbit. A final circularisation burn brought my periapsis above 70km.

 

Album link because stuff's broken: https://imgur.com/a/0XXiA

 

Result: 3.66t to LKO for ROcket 10!

If I do a next attempt, I'll be focusing on the second stage: I feel like the Terrier is giving me plenty of TWR that the upper stage doesn't necessarily need. I'll see what I can do with a smaller (and lighter) engine.

Edited November 28, 2017 by Gaarst
Fixed album link

[Human Person]

I can't delete my own content, only edit it.

 

Edited June 25, 2017 by Physics Student

[GoSlash27]

Gaarst,

 Amazing! 3.66 tonnes is way beyond what I thought caveman tech could do.

Best,
-Slashy

[sevenperforce]

What exactly is the part list on this?

[Gaarst]

9 minutes ago, sevenperforce said:

What exactly is the part list on this?

The five first nodes of the tech tree. I created a career mode and cheated myself a couple thousand science to unlock all these.

Spoiler

 

[Cunjo Carl]

Caveman aircore reporting in! Latest invention called Huck.

Huck's the latest in a long line of caveman spaceplanes designed for lifting Mun-bound craft. This is by far the highest tech caveman spaceplane I've attempted, with the Wheesely at a whopping tech level of 5! The core idea centers around two key features: Wheesleys can get you to 10km,500m/s for free where terriers become effective, and wings let you fight gravity with fewer/smaller engines making terriers effective. The downside is Airbreathers are heavy, wings are heavy, and nose cones... are heavy! Also, it takes a lot of effort to optimize the flight path. Do you push for high altitudes for their better drag+Isp, or keep it low and bank on your speed to carry you through? With this craft it takes a bit of both, resulting in a dolphin path up to orbit.

Still, the results are lovely.

Huck

  

  

 

The pictures should zoom in when you click on them... I think . Huck pushed 4.5tons of pristine FL-T800 to orbit.

Edit: I just noticed the separable payload requirement so I ran it again with an isolated FL-T800 with a tick of oxidizer removed for 4.28tons. It reached orbit with ~.1ton fuel/ox to spare, but with no transfers it's limited to the full tick removed.. Kinda felt bad splitting the thing off its engine and probe core, but that lone wolf tank is chilling in orbit so there we have it!

Edited September 6, 2017 by Cunjo Carl

[fourfa]

I'm in the doldrums of the Caveman Challenge, and was thinking of starting this exact challenge to see what people have come up with for caveman lifters.  Lo and behold, this challenge already exists! Unfortunately all the screenshots are broken links, and someone seems to have deleted a lot of content...  I'd love to see the lifter that tossed up 3.66t

[Gaarst]

49 minutes ago, fourfa said:

I'm in the doldrums of the Caveman Challenge, and was thinking of starting this exact challenge to see what people have come up with for caveman lifters.  Lo and behold, this challenge already exists! Unfortunately all the screenshots are broken links, and someone seems to have deleted a lot of content...  I'd love to see the lifter that tossed up 3.66t

Here: https://imgur.com/a/0XXiA

That was 5 months ago, so there probably have been like 200 updates that each individually broke albums; hopefully links won't break any time soon.

Edited November 28, 2017 by Gaarst

[GoSlash27]

Cunjo Carl,
 My apologies for missing your entry. That's pretty epic, and I've updated the leaderboard with you at the top.

Best,
-Slashy

[Andetch]

Andetch CavemanTech SSTO Re-Usable Rocket.

It's payload is so small, being pretty much only the command pod that the pilot uses, we won't speak of it.

It IS however fully re-usable and SSTO.

Enjoy!

https://kerbalx.com/Andetch/Caveman-SSTO-Lifter

 

Edited March 30, 2018 by Andetch

[Andetch]

I've just re-read the rules and realize that as my "payload" was the Mk1 command pod it violated the rules, so I've made a redesign. Will post the video ASAP

[JAFO]

On 6/26/2017 at 5:39 AM, Gaarst said:

I took my previous lifter, reinforced the lower stage, now powered by one Reliant and 4 Sparks (Vernier hype) instead of the dual Thuds, giving much higher TWR at launch.

https://imgur.com/a/0XXiA

 

I just wanted to say, many thanks for this brilliant idea! This allowed me to remove the two Fleas I'd been using for liftoff assistance on my Caveman Challenge's crewed Minmus lander (aka The Flying Sparkplug), thereby allowing me to add considerably more fuel instead. This resulted in a little extra fuel remaining after reaching LKO, meaning there's now a small fuel safety margin, instead of the razor-thin margins of past flights. I'm hoping this may even be enough to let me hit two biomes on the one trip, though this remains to be seen.

[Rakaydos]

I've been working on debugging my Skipper-based Caveman Build-a-Rocket, and recently worked out that my 2 stage 2.5m design (which can be asembled with reasonable reliability) has a payload to orbit of about 4 tons.

I'm about to try designing 3rd stage into the Payload Adapter assembily, with a potential payload increase to ~5-7 tons while still fitting in my per-segment mass budget. (assuming the extra mass doesnt cripple my poodle stage's ability to get  out of the atmosphere)