Laythe Land and Return

[Anglave]

I undertook a multi-part mission to Laythe. Stock .19.1. All manually piloted.

The first craft is the science station, lander, and the return section. craft file.

The second craft is two major interplanetary stages, designed to push the mission to Laythe. craft file

They dock in LKO, then push outward to Jool.

and aerobrake together at Laythe

At their new Laythe apoapsis, they un-dock, and the IP stage (Starlance) makes a small prograde burn, taking up a communications relay orbit,

while the lander section makes a second aerobrake pass, descending to a landing trajectory.

After landing, the crew descends to the Hitchhiker science lab, which will remain on the surface.

The crew does Science! until their return launch window. Then they climb back into the control capsule and ascend to LLO.

The science station remains on the surface of Laythe, in communication with the orbiting interplanetary drive section, which acts as a relay to Kerbin.

After attaining Laythe orbit, it's a simple matter of plotting a Kerbin intercept and waiting for the long fall back home.

The complete photo album is here.

[AntiProtector]

u done this job.. but your ship is a like a crismas tree..

gj... well done..

[StainX]

This looks more like its used for eve+return!

You could build this with much less parts for just one kerbal. But well done!

[Anglave]

u done this job.. but your ship is a like a crismas tree..

What does "like a crismas tree" mean? My ship is festive and pine scented? It's ornamented? I get that it's decked out in lights, but...

This looks more like its used for eve+return!

You could build this with much less parts for just one kerbal. But well done!

But I sent three

And left a Hitchhiker (with lights and science instruments) on the surface.

I'm curious, both responses seem to imply that I've over-built. Is there a significantly more efficient way to do this mission?

[Mulbin]

I'm curious, both responses seem to imply that I've over-built. Is there a significantly more efficient way to do this mission?

Laythe ships will always be big! Well done for getting there and back But designs can be refined to make the most of Delta V.

This is really out of date as it's my last ship still waiting for an update (made it in .18). Gets three kerbals to Laythe and back in a single launch, I've learnt a lot since then so will have a much smaller launch vehicle next time.

Original thread got wiped in the crash but here's the link to the Craft! Will start a new thread when I update it. Ignore the mod buggy in the pic... this is the stock version of the file.

http://www./download.php?x1svro3srv2m0gv

Keep up the good work!

[StainX]

Is there a significantly more efficient way to do this mission?

Sounds like its "challenge time!!!!!" (try that after work)

But i give you a few suggestions, if you please:

• Its all about deltaV so you may do a lot of Slingshots+Aerobraking.
  
• Less is more, so may only use one nuclear engine for transfers which means less mass and more deltaV.
  
• Only send one kerbal to Laythe or at least on the surface.
  
• Find a way to use fueltanks efficient and decouple all the empty ones in flight.
  

Edited May 8, 2013 by StainX

[Flixxbeatz]

The second pic looks more like a stack of boosters than a rocket for me.

[Conzolax]

Great job

And as long as you had fun doing it, nothing else matters really.

I do however, agree that it could have been done with less parts and abit more efficient.

Just as an example, my first working Laythe return rocket looked like this:

This isnt THE craft i did it with, since i dont have the craft anymore, its just redone from memory (except the lander).

The Delta-v might seem on the low side, but the craft does get lighter as you go (disposable sidetanks and middle section, only command module returns ect), so it will have quite abit more Delta-v than Mechjeb tells you.

It does however, rely alot on aerobreaking when you get there, both around Jool and Laythe itself.

The lander however, goes to 80Km Kerbin orbit with 100 fuel to spare, and is more than enough to get into orbit on Laythe.

Point is: It CAN be done with less

[Anglave]

Does that lander use jet power only to re-orbit? That's very interesting, you need to carry a lot less fuel into Laythe's well that way. And of course, you're not leaving a payload on the surface or an orbiter at Laythe.

Ok, I haven't done the calculation, but I get how the single NERVA pushes everything in the image to a Laythe aerobrake encounter, expending the bottom 4 tanks. Then you'll decouple (the top gray tanks and above), and descend to a landing trajectory. And I see chutes and jets which should provide a soft landing. And I can believe that the jets push it back into orbit.

What I don't see then, is any way for it to leave low Laythe orbit. What am I missing?

[Conzolax]

@Anglave

Basicly, when you move away from Kerbin, the nerva uses fuel from the side tanks on the orange tank first. When they run dry, i ditch them.

When the orange tank run dry, you can remove it, and continue on only using the lander and bottom section of the drive (grey tank+nerva). The bottom grey tank is attached to the orange tank with a docking port.

The lander has the smallest liq+oxy tanks on the sides, the ones the jet engines are attached to.

It also has a poodle engine in the bottom.

It takes of from Laythe (or Kerbin) using only the jet engines. When the jet engines start to flame out, i shut them down, and run on the poodle.

When the side tanks run dry of liquid fuel, i ditch them along with the landing gears, jet engines and so on.

After that, i re-dock with the small grey tank+nerva, tranfer whatever fuel the lander has left, ditch the bottom of the lander section so only the command module stays, and return home.

^This is the only thing returning home from Laythe. Yup, i know it looks ugly

Edited May 8, 2013 by Conzolax
Picture

[Anglave]

What I don't see then, is any way for it to leave low Laythe orbit. What am I missing?

Ahh, I was missing the docking ports, and re-docking the lander in Laythe orbit. I mistook the object at the tip of the command module for a parachute, rather than a shrouded docking port. Thanks for the detailed explanation!

Do struts auto-break when you un-dock, the way they do when you decouple? I hadn't realized that.

Edited May 8, 2013 by Anglave

[Conzolax]

You're welcome

And yes, the struts do remove themselves when undocking/decouple.

Oh, and btw! I hope i didnt come off as trying to lecture you or anything, that wasnt my intension if so.

The thread just moved into a discussion about doing it more efficiently, and i just wanted to give my input.

Personally i think your ship looks awesome when its docked with its drive unit in LKO.

Edited May 8, 2013 by Conzolax

[StainX]

Here is Img-Album of my Laythe travel... well the game was kinda bugged while loading a savegame that made my lander go "Kaboooom",anyway i guess that thing had far to less thrust for an good ascent.