Halp! My Kerbals are stranded!

[butterknife]

I got ambitious. I didn't plan enough. I sent Jeb, Bill, and Bob to Duna without enough DV to even get back into orbit for a return flight. I need to send a rescue. The three may have sent back a sizable amount of science, but it wasn't worth their lives. They were able to transmit enough science, that Kerbodyne was able to create the KL-2L and requisite fuel tanks in anticipation for this mission's booster requirements.

But I'm not really sure what the rest of the ship should look like. Any tips?

Edited July 12, 2014 by butterknife

[butterknife]

I'd also like to send a rover, in case I can't land close enough to them. But I had a heck of a time trying to detach the last one and get it down to the ground on the one I sent with our three heros. Should I just use like, a probe core to guide a mini rocket pack lander?

[Mechie_PhD]

Depends on what mods you have. Looks like you don't have remotetech, but if you have any life support mods, time would be an important factor. If you are playing the stock game, let them enjoy their vacation....

[Master Tao]

The rescue ship will depend quite a bit on how you plan to get them back: a new lander or refuel the existing one. My standard Duna lander uses one of the shortest 2.5m tanks, so if I ran low, I'd just add a bit of fuel using a rover-glider with a claw. You could also send an upgraded version of your existing lander.

[Oafman]

It sounds like 2 things are required; a lander/ascent vehicle with more dv, and a vehicle to return from orbit with more dv.

Are you able to rendezvous and dock ships in orbit? If yes, great. If not, it's probably time to learn!

Because sending a ship which can land on Duna (close to your kerbals!) launch from the surface, reach Duna orbit, and then return to Kerbin is much harder than building a ship with a detachable lander, which can return to the mothership in Duna orbit, dock, transfer crew, ditch the lander and return home. (it's certainly possible to build a single ship to do it all, but is a much bigger engineering challenge, and may not be possible with the parts you have available).

You could go for a design along the lines of the below image, which I recently sent to Duna. It had plenty of dv (way more than was necessary to get back into orbit), mainly because it had aerospikes, which are very efficient. If you have unlocked them, they're a good option for Duna. If not, there are alternatives.

This craft was actually for 2 kerbals to return. But you could easily replace the materials bay with a MK1 lander can - it has plenty of dv & TWR to spare. Note that the extra fuel tanks on the sides detach half way to orbit, and of course the rover is left on the surface, so the ship has quite low mass by the time it is circularising its orbit.

One issue you will have is getting the new lander close enough to your Kerbals. Jetpacks do work on Duna, but they won't get you too far. And walking kerbals for miles is a miserable experience, especially one at a time with 3 of them, so you want to land as close as possible. And trying to do that by eyeballing it is difficult, and takes practice. So I think your best solutions to this are (i) get Mechjeb to land it for you - it is very accurate, or (ii) take a rover, land manually, as close as you can, then drive to collect them and bring them back to the lander. The problem there is you'll need a bigger rover than I took, as mine had a capacity of only 1 kerbal. But it can be done.

Good luck.

[butterknife]

I don't believe I've got aerospikes yet. I really haven't messed with the space plane tree at all. It's been all rocketry, research, and probes. There's a big chunk in the middle where I haven't even really touched. I've neglected to even get the nuclear engines. My kerbals fear the big triangular warning signs. I like the idea of a lander can rover, though. I think I'll do that. The lander they came in on got knocked over. Totally the fault of Solar Winds, and not shoddy piloting or engineering. Yup. Solar winds.

Anyway, it's not getting back up. My only real option is to send a new ship down. And also, it'll have to be able to gather the same research they had. Because science cannot be left behind.

I'm kind of considering leaving a science lab, and one volunteer behind. You know. For research purposes.

I don't have a claw available. Claws are scary.

[Roastduck]

You can transfer science between ships easily. That won't be an issue. Can you post .craft files of the relevant ships and a screenshot of your current tech tree?

[butterknife]

When I get home, sure. I'll figure out how to do that. What if I just grabbed the save and posted that?

[cantab]

I'd also like to send a rover, in case I can't land close enough to them. But I had a heck of a time trying to detach the last one and get it down to the ground on the one I sent with our three heros.

One way round this problem is landing your rover and ascent vehicle separately.

[Roastduck]

When I get home, sure. I'll figure out how to do that. What if I just grabbed the save and posted that?

I didn't even think about that. Can a grizzled KSP vet confirm if this is even doable? I don't see why it wouldn't be

[EdFred]

I didn't even think about that. Can a grizzled KSP vet confirm if this is even doable? I don't see why it wouldn't be

Yep. Post the persistence.sfs file somewhere. Download, dump into a folder resume saved, and voila.

[butterknife]

Here's a link to my entire career folder. It's got the persistence.sfs file, my last quicksave which should be where I landed my intrepid trio, and also all my saved ships. Warning, they're not that inventive. They're just big. And loud. And they don't have RCS, because inline stabilizers are all you really ​need.

https://dl.dropboxusercontent.com/u/32848101/KerbalCareerFuntime/KerbalCareerFuntime.zip

[butterknife]

Aaaand apparently while messing around in those files, I deleted all my parts. . . Huh. Well. At least I still have my save file. Gonna go use steam to check my game integrity.

Reinstalling. Then I'll drop my career file back in. Cross your fingers, or Jeb's dead for real this time.

Edited July 10, 2014 by butterknife

[butterknife]

None of my parts are loading. I thought I cleaned out an old Kethane mod, the H.O.M.E. mod, and mechjeb, but it looks like I deleted all the standard resources too. Not sure how to fix it, now.

Edit: Fixed. All is well and as it should be.

Edited July 10, 2014 by butterknife

[Roastduck]

i'll see if i can load it up in a bit. not sure how well it will work, since you seem to be using different mods than me, but i'll give it a shot

[team.leit]

What mods are you running? I am willing to give this a try later tonight after I finish my chores.

team.leit

[butterknife]

I had kethane, home, and mechjeb, but I didn't use any of those in career. So I did a fresh install, and dropped the save file into it, and it loaded up perfectly.

[Roastduck]

Okay, I've modified your original lander a little bit. You should still have plenty of delta-v to get to Duna, land, and return. No crew on the trip there, so you can just load your Kerbals and science into the pod and blast off

https://www.dropbox.com/s/b2qqd3bceq3j4vz/Duna%20Rescue%20Lander.craft

I just added 4 LT-800s in asparagus staging on the side, added more landing legs to help accommodate the weight, plus a streamlined your electrics. I also added parachutes, because you had forgotten them. Those will be important for reentry on both Kerbin AND Duna. I got rid of the rover and put a stayputnik in its place, since you really don't need two rovers in the same area, do you?

[dryer_lint]

Make the rescue ship remote controlled with no pods, just external seats. To... umm... save weight.

[Kerba Fett]

Perhaps you're just looking at this from the wrong perspecitve. Sure you could call them stranded, OR they could just be the first members of your new Duna colony just waiting for the rest of the base modules to arrive.

[butterknife]

Okay, I've modified your original lander a little bit. You should still have plenty of delta-v to get to Duna, land, and return. No crew on the trip there, so you can just load your Kerbals and science into the pod and blast off

https://www.dropbox.com/s/b2qqd3bceq3j4vz/Duna%20Rescue%20Lander.craft

I just added 4 LT-800s in asparagus staging on the side, added more landing legs to help accommodate the weight, plus a streamlined your electrics. I also added parachutes, because you had forgotten them. Those will be important for reentry on both Kerbin AND Duna. I got rid of the rover and put a stayputnik in its place, since you really don't need two rovers in the same area, do you?

This almost worked. I wasn't paying attention, though, and I was moving for orbital insertion in Duna's SOI, and instead of decoupling my transfer vehicle, I decoupled the four fuel cans around the lander.

Oops.

[butterknife]

Make the rescue ship remote controlled with no pods, just external seats. To... umm... save weight.

Wouldn't my kerbals burn up on Kerbin reentry? Would the seats even hold?

Shoot, that's like strapping your cousins to the hood of your dad's van, and then traveling cross country non stop. . . I need to try this.

[dryer_lint]

Wouldn't my kerbals burn up on Kerbin reentry? Would the seats even hold?

Nah, at the moment there's no re-entry damage in KSP UNLESS you have Deadly Re-entry installed.

Just make sure you have drogue parachutes (the orange ones) or the force of parachute deployment might rip apart your ship.

[Claw]

Claws are scary.

Sounds like you're getting plenty of good help for this. However, I'd like to point out that I am NOT scary. (Well, maybe it depends on who you ask...)

[Roastduck]

This almost worked. I wasn't paying attention, though, and I was moving for orbital insertion in Duna's SOI, and instead of decoupling my transfer vehicle, I decoupled the four fuel cans around the lander.

Oops.

I actually didn't do ANY staging when I reworked the lander. That's my fault. If you stage it so that you still have the four tanks on your descent, you should have PLENTY of fuel for both landing and return