33.46 Ton Lifter?

[Stevenator1]

Editing the post a little bit to seem like less of a noob, because I certainly am not one: Also, 334.6, not 33.46.... derp...

Hey guys,

Does anybody know of any good heavy lifter designs? I've looked in the Design forum, not much comes up. Is it even possible to get 334.6 Tons into space?

If it is hard/impossible, any way to design a lighter eve lander and return system? My best design that I can come up with that has the delta-V requirements, along with the delta-V to get it from Kerbin to Eve, takes 334.6 tons. I've never been able to design a lifter that can get that much mass into LKO.

Not to mention there is probably an easier way to get to eve and back without using 334.6 tons.

Edited October 18, 2012 by Stevenator1

[Temstar]

Asparagus staging - learn it, love it. You can see an example I posted here that lifts something like 80 tons to LKO:

http://kerbalspaceprogram.com/forum/showthread.php/24015-Avoid-roll-and-ASAS-flexing-during-ascent-with-vertically-staged-rockets?p=298684&viewfull=1#post298684

An Eve return mission will take a lot more than 33.46 tons from LKO I think. You need something like 12,000 m/s delta-V to get back to low Eve orbit from Eve surface if you are using pure rocket power. I firmly believe the best way to reach orbit from Eve surface is a convertable spaceplane that can stage into a pure rocket.

[Stevenator1]

*removed because of tired post*

Edited October 18, 2012 by Stevenator1

[Punk]

Yeah, I use 4 stages. 9, 5, 3, 1. That is 9 tank and engine stacks arranged in a 3x3 formation and fuel line linked so that the 4 corner stacks (1,3,7,9) feed into number 2 and 8 stacks which feed into number 4 and 6 stacks which feed into the middle stack, 5. Add some solid boosters for bigger loads and drop empty tanks when they burn out. This can get 150+ tons into LKO, it can be a little over kill though if you are going for a minimalist approach. But bigger is always better.

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[AmpsterMan]

I had a 50 tn LKO rocket at some point. I think the things to keep in mind are asparagus staging and using aerospikes. Developing the delta-v needed to get that mass into Orbit and maintaining at least a workable TWR is a difficult balancing act.

[blurrr 2]

I used two 50-ton launchers for my Duna mission: one to launch the Duna lander, and one to launch the Ike lander and return ship.

Transferring Kerbals to another return ship really helps improve efficiency, because then the lander doesn't need to carry all the fuel to get back.

[1of6Billion]

I have been trying to land 56T on Mun. No matter what I tried, it runs out of fuel 300m - 5km from the desired landing location.

[Gunhed]

Hi,

here's my heavy lift design.

Started with around 920 tons (Stock parts)

http://youtu.be/p9KF85vCNTM?hd=1

Hope it helps!

Cheers,

Gunhed

Edited October 16, 2012 by Gunhed

[EndlessWaves]

The delta-v should be able to lift it.

But can it lift itself as well? Eve has higher gravity so while you can get 11,000 DeltaV from 60 tons on Kerbin you'll need to add extra engines, their extra weight and extra fuel tanks to compensate and get off eve.

Adding an interplanetary stage to 60 tons and lifting the whole lot doesn't require a particularly large or complex rocket, six mainsail engines with 5-6 drop tanks each should do it. I guess the problems you're having are stability related as payloads with lots of parts tend to be rather wobbly and those are hard to solve without knowing the cause.

Part count tends to be the limiting factor rather than weight so while you can get 400-500 tons of 18 ton fuel tanks to orbit in less than 300 parts you're often limited to less weight if you want to add lightweight but useful parts such as engines. Still, as long as you're not going over 150-200 tons it's definitely possible to build a reasonable rocket to get the payload to eve.

[azazel1024]

I don't have a picture of my lifter handy, but I got this bad boy (okay, it isn't that huge) in to LKO. Freedom Station I. I lofted it last night and I plan to do an orbital rendevous tonight (my first, hold me, I'm scared) to transfer over another couple of Kerbals to it. Total mass is around 25t. I know that is below your limit, but I had tons of fuel left over. Litterally. My final ascent stage had two large fuel tanks and I had barely used one of them before I got to a nice circular 320km orbit above Kerbin and jettisoned it. My rocket was a simple 3 stage affair. 6x6x1 arrangement with no SRBs (6 lower, 6 upper and a single center upper rocket motor, jettisoning as they ran out of fuel). If I had used SRBs and burned through all of the fuel in my final ascent/orbital stage I could likely have lofted at least 35t. If my final stage had used a cluster of nuclear rockets instead, I probably could have gotten at least 40t in to LKO.

That said, I currently suck at really good heavy lift designs. Much more complex/bigger than what I have currently built tend to blow-up on launch, disintegrate and/or are uncontrollable. I am still playing around with it though. The hardest for me though are lofting big stations as it is hard to get a really nice symetrical design (both center of mass and drag) that allows the launch vehicle to be controllable.

I am really looking forward to docking, though I am about at the point of trying out some of the docking mods as well as the remote tech mod (interplanetary probes, check!).[ATTACH=CONFIG]34882[/ATTACH]

[Qumefox]

This will get 30t in a 100km KLO reliably.. but 30t is pretty much the limit for this build without having to use fuel in the final stage.

http://kerbalspaceprogram.com/forum/showthread.php/23955-0-17-Quickie-Mk-I-%28Generic-medium-lift-capacity-launcher-orbiter%29

More SRB's might push the load limit up to meet your need.. Most of my orbiters/landers have ended up either being <30t or >50t.

[Whatshtisthis]

I got 66 tons into LKO with the huge tanks and the 1200 thrust engines.

Asparagus staging does wonders, also attach some SRBs to the sides.

[Stevenator1]

I should have rephrased my question - I'm no noob, I know asparagus staging, SRBs, and Aerospikes. I was also looking for efficient designs, trying to get that mass up there with as little launch mass as possible.

[Whatshtisthis]

Here is a rocket you should NOT build, it's lags like crazy.

[AmpsterMan]

I should have rephrased my question - I'm no noob, I know asparagus staging, SRBs, and Aerospikes. I was also looking for efficient designs, trying to get that mass up there with as little launch mass as possible.

If you don't mind waiting a few hours, I'll post mine. It can take 50 tn to lko and has a launch mass of 390 (that is, including the payload)

[m1xte]

More parts more lag.

Stage 0

Something

Stage 1

Mainsail with 5 or 6 big tanks on top + 6x the same pile strapped around it with symmetry without decouplers.

Stage 2

6x mainsail with 4 or 5 big tanks on top around stage 1 with decouplers.

[AmpsterMan]

As promised, here is my most efficient rocket yet!

Give it a whirl, lemme know what you think.

[Qumefox]

needs a parachute and asas (for us non-mechjeb users) the staging can be simplified since the first boosters and the first droptanks empty within a second of each other. so you can just hang on to the srb's for another second and dump them both at once.

You also have a staging issue where two of the top stage aerospikes are lighting in the first stage, and burning through the tanks below them.

after fixing said issues, I got it into a 100km lko with 902m/s remaining on it.

now to try some tweaks I think might help and try again.

launch 1: 902 m/s remaining - base design

launch 2: 928 m/s remaining - fired all four SRB's at launch instead of staggering them.

launch 3: 975 m/s remaining - above + replaced all the LV-T30's with aerospikes+engine housings (so they could be attached to the tri-couplers... stupid aerospikes)

Edited October 17, 2012 by Qumefox

[AmpsterMan]

well that ship was designed to have the payload on top of the Pod. I did it by loading 45 tons of stuff up top. I just deleted it all before posting it. I usually put my ASAS in the Payload stage because I want to use that for my transfers as well. This was just meant to be a launcher

Edit: just noticed what you were talking about the Aerospikes; yeah they were supposed to light during stage 8

Edited October 17, 2012 by AmpsterMan

[Qumefox]

Still doesn't explain the 2 top stage aerospikes firing through the tanks below them. heh.

anyway. Result of the first tweak added to my above post.

[Qumefox]

Testing done, results posted in above post.. Can be tweaked to be a bit more efficient, but not a lot.. about 8%.. But that's 8% more weight you can carry on the same fuel load.

numbers might vary slightly since I was flying manually, but my orbit procedure is pretty repeatable, and i've done it enough to be decent at putting stuff right at 100k every time.

[Gunhed]

Have a look and try at this one.

Mechjeb is adviced...

Edited October 17, 2012 by Gunhed

[Qumefox]

I don't use mechjeb. It's not installed, and never will be. Plus that looks like way more than is needed to get to duna, land, and get back.

[Ziff]

Hey guys,

Does anybody know of any good heavy lifter designs? I've looked in the Design forum, not much comes up. Is it even possible to get 33.46 Tons into space?

If it is hard/impossible, any way to design a lighter eve lander and return system? My best design that I can come up with that has the delta-V requirements, along with the delta-V to get it from Kerbin to Eve, takes 33.46 tons. I've never been able to design a lifter that can get that much mass into LKO. Any ideas?

Sure, it's totally possible. I managed to get 154tns to Minmus in .16 (with a fixed fuel bug patch.) Can you upload the .craft file for your lander and I will see if I can dig-up and retrofit my lifting stage to it? I'll go dig it up now and check it.

[sjwt]

something like this?