First Mun mission and got stranded, can't seem to rescue Jebediah!

[ipv6guy]

I've been trying to mount a rescue mission to pick up Jebediah who is orbiting around the Mun.  He ran out of fuel and is simply unable to get home O_o

For the life of me I can't seem to build a ship capable of making it to the Mun, performing intercept maneuvers to get close to him, and then has enough fuel to make it home.  Most of my ships seem to just falter even getting into orbit at this moment due to how much fuel I'm trying to carry.  All my previous ships can -get- to the Mun, but once they get there they too are unable to make it back.

So what's my best option here? Should I build a low orbit docking + fuel station, or is there some way to build a ship capable of doing everything I need with tier 4 branching into tier 5 tech?

[Snark]

47 minutes ago, ipv6guy said:

So what's my best option here?

Broadly speaking, there are two classes of problems you can run into when your ships won't achieve what you want to:

1. You're building them wrong.
2. You're flying them wrong.

Without seeing what you're building and how you're flying it, it's hard to give specific advice.  There are a lot of ways to be "wrong" in KSP!

Suggestion:  Post a screenshot of your attempted ship.  One shot on the pad, one shot when it's in LKO.  That way we can give specific suggestions on how to improve the ship, if there are clear issues with the design.

The other thing that would be helpful would be getting an idea of how you're flying it.  Can you describe what your process is for getting to orbit, for example?  Describe your attempted flight path to Mun orbit.  (In your description, one data point that would be useful to know:  when your ship reaches 10 km altitude, how fast is it going and about what angle is it from the vertical?)

 

[bewing]

Getting to Munar orbit and back is certainly doable with Tier 4 tech. It's a good thing Jeb isn't on the surface -- that's much harder, but still doable.

Snark didn't specify, but when you post a pic of your ship in LKO -- go into map view, and click on the "i" button -- and write down the current mass of the ship. And tell us how much fuel you have left.

One additional thing -- have you upgraded your Astronaut Complex yet? Or is it still Tier 1?

 

[DD_bwest]

  are you sending an unmanned rescue, or are you sending the 3man pod?   because using a mk1 pod with a probe core attached would use much less fuel, so in a way much easier.   Also, do you have propulsion systems?  an Mk1+heatsheild and chutes is rather light, the spark with even a tiny amount of fuel can go a long way,  infact, 1 oscar B in the center, 4 around its sides with fuel lines leading to the center tank would be around the 1200m/s range for delta V, .   and with a heatshield, you can simply set a 30km pe around kerbin leaving mun and youll come back safe.

The next question would be how you are doing it, specifically how much fuel your using  within Mun's SOI.   if you let us know what your steps are, we might be able to give some pointers to do things more efficiently.

hope we can help!

Edited August 9, 2016 by DD_bwest

[Foxster]

6 hours ago, ipv6guy said:

 Most of my ships seem to just falter even getting into orbit at this moment due to how much fuel I'm trying to carry.  

With KSP, it is tempting to think you need some massive Saturn-5-like craft to go to the Mun and back. This is not the case. 

Install a mod (MechJeb or KER) that tells you the craft's dV and TWR. You want 6000+ starting dV for a Mun orbit return mission.  Your TWR wants to be between 1.2 and 1.5 or so for the first stage, reducing towards 1.0 for the other atmosphere stages. Once out of the atmosphere, the stages' TWR can be as low as you like. 

Depends what tech you have unlocked but something fairly low-tech like this would do the job...

You'd launch crewless, hence the need for the probe core, which can be ditched once the crewman is aboard. 

Once you have your man, leave the Mun's SOI. Then set your Kerbin Pe at about 20-30km. Dump everything but the capsule (and heat shield and solar panels) and you can then sail to Kerbin's atmosphere and re-enter. 

Edited August 9, 2016 by Foxster