Oh No!...Poor Bob! - Leave No Kerbal Behind!...?

[Fubarbrickdust]

So I have a bit of a dilemma, my first real one in the game and was hoping to get some advice to consider whilst planning my 1st self imposed 'contract' mission (or not, as the case may be)...

I'm a relatively new player but quickly learning the ropes - I'm at the orbital rescues/put 1st satellites up in orbit/land on The Mun phase of a career game (i've pretty much unlocked the majority up to tier 5 on the tech tree) and up until now it's been a pretty successful career - I've been taking it slow and not rushing things while I learn, and only really been using the 'load quick save/revert to launch to correct obvious schoolboy errors and hideous design flaws whilst experimenting...such a fun game!

The land/gather science from on and around/plant flag on The Mun contracts have been on the books for a while now and I'm happy to report that we have success! - Bob Kerman has made the 1st giant leap for Kerbal kind!

But here's the thing - He's stuck there.

In all fairness it wasn't the most efficient of launches...but I had a quick look at the fuel/Dv. Loads, he'll be fine...

In all fairness it wasn't the most efficient of landings...downright sloppy in fact, but the best I could do with my current skill level (I'd had a few F5/F9 practices in the run up) I just didn't realise how much Dv I'd spend getting down to to the surface safely.

Bob had a whale of a time bouncing around The Mun planting his 1st flag and collecting all that juicy science, however.

And then he got back into the Mk1 CP and realised that he has a little over 50 units of fuel in his lander...Meh, he's an optimist...The Mun's gonna be a doddle to get up off/swing home from, right?

So. I now realise that this is not enough to get Bob and his lander back home. Through a bit of F5/F9 experimentation, Bob and I are now in a position that the fuel we have left it 'just' enough to get us into a stable low Mun orbit...nothing more. Not with the experiment loaded craft we have. So I've F5'd back to our landing site to keep the options more open, spent a minuscule amount of Dv getting our solar panels pointed at Kerbol, transmitted all the data i can get 100% for...then headed back to KSC to think about how to get him home (preferably in his lander too, if at all possible).

Options I've considered so far:

1. Load the .sqs save that I made before launching the mission. (Last resort, if at all - totally not in the spirit of the game, too easy. Besides, a lot of other stuff has been progressing while Bob was on the way to The Mun.)

2. Leave him there. He won't die. Maybe come back and get him when I'm so advanced that it'll just be like taking a quick detour. (Again, not my 1st choice. It's Bob! Plus there's quite a bit of science up there with him that I'd like to go in the kitty. And again, I don't think that's too spirited - I think it'd be KSC's top priority to bring him home).

Realistically:

3. Send an un-manned probe vessel/lander with another CP or Can for Bob (better designed/fuelled this time). Either land it at the site or put it, and Bob into orbit then EVA over > Go home! - This is probably the sensible option, and to rendezvous in orbit of course. But it would be nice to get him and the lander back together. So...

Ideally:

4. Send an 'over engineered' rescue boat with enough fuel to transfer some over to Bob's lander and get everyone and everything home. Crewed with Bill (Engineer), KIS, KAS and EVA transfer mods installed, using mission option:

4a. Land at site. 'EVA transfer' fuel over to Bob's lander - GTFO of there. (Can this be done/does this mod work whilst in a close encounter orbit?)

4b. Rendezvous in close orbit - EVA Bill over, whack on a docking port to Bob's lander using KIS, dock, transfer fuel, GTFO of there.

------- ------ ------

So that's the ideas Ive come up with so far, any thoughts or advice on these ideas, or any alternates are most welcomed and requested - He is coming home!

However, given the calamity I've made to get here, I could probably do with all the wisdom you guys can offer. Any help please?

TL;DR = I've stranded Bob Kerman on The Mun - What would you do?

Edited October 30, 2015 by Fubarbrickdust
...more spelling mistakes :/

[NGTOne]

I'd do 4a, personally - leave a cool bit of debris on the Mun as a memory of a mission (almost) gone wrong.

[Randazzo]

If you can get him into a stable orbit, you're halfway to rescuing him. Manned or Unmanned is not all that important, what matters is that you've got space for your Kerbal on the rescue end and that the vehicle can survive Kerbin reentry.

[LostOblivion]

Exactly this happened to my Jeb when he went to the Mun for the first time. I sent an unmanned probe to get him. :-)

[Waxing_Kibbous]

Hang out for a bit until you get a Mun contract that will allow you to both fulfill it and pick Bob up. If you have a shortage of scientists then sure go grab him, but I'd wait for an appropriate Mun contract. I mean, look at Bob's face and tell me he isn't enjoying himself up there!

[GoSlash27]

He must be rescued!

I need some vital stats on his ship.

-What is his fuel supply (units of fuel and o2)?

-What is the mass of his ascent module?

-What kind of engine is he using?

I want to verify the DV.

Best,

-Slashy

[Fubarbrickdust]

If you can get him into a stable orbit, you're halfway to rescuing him. Manned or Unmanned is not all that important, what matters is that you've got space for your Kerbal on the rescue end and that the vehicle can survive Kerbin reentry.

Yep, that's what I thought when I decided to F5'd back to the Mun landing site where we still had a bit of fuel left - I'm thankful for that at the least, it means there are more safer options if I choose to pursue them. (I initially tried to break the Mun SOI and failed, leaving Bob in a very unflattering orbit which would have been less straight forward to rendezvous with)

Exactly this happened to my Jeb when he went to the Mun for the first time. I sent an unmanned probe to get him. :-)

It's reassuring to know that I'm not the only one I take it that the mission was a success? How's your Jeb doing now? Recovering from the distress, I hope.

I'd do 4a, personally - leave a cool bit of debris on the Mun as a memory of a mission (almost) gone wrong.

I really like the idea of doing this. It'd be really cool to pull it off, especially at my level. Although, I am viewing these options with a healthy amount of caution. As before, I'm clearly not the most honed of Kerbonauts - There could be a new thread turning up in a few days entitled "I've stranded Bob, and Bill on The Mun...What would you do?"

I've already had a go at putting together a payload and delivery package that's capable of doing option 4a - so far the results aren't that confidence inspiring. I seem to be coming up against a wall where I effectively end up using just as much fuel (proportionately) to get where it needs to go. I think it's either that I'm rushing it, haven't unlocked good enough tech, or, more likely I'm taking too much of a leap in my rocket design 'learning curve' to build a (moderately) heavy delivery/payload combo. It's probably a combo of the 1st and last one to be honest :/

I'll keep exploring it to be sure though...

[CrashTestDanny]

Send another manned mission with a spare seat for him. Terminate the other craft after he's home. That's how I handled it. I don't think a Kerbal can reach Mun orbit on their EVA pack, and 50dv left in his lander isn't going to put you there, so I would go with a precision landing 50m from his position (if you're near the equator, that's about 50 arc seconds I think... I use Mech Jeb for precision landings and usually use between 20 and 50 arc seconds delta when landing next to something else).

Danny

[Fubarbrickdust]

Hang out for a bit until you get a Mun contract that will allow you to both fulfill it and pick Bob up. If you have a shortage of scientists then sure go grab him, but I'd wait for an appropriate Mun contract. I mean, look at Bob's face and tell me he isn't enjoying himself up there!

I like this ...I didn't consider it. I just had a 'Must Save Bob' instinct and rushed to get the rescue going. I might merge this with one of the other choices as option 5.

He must be rescued!

I need some vital stats on his ship.

-What is his fuel supply (units of fuel and o2)?

-What is the mass of his ascent module?

-What kind of engine is he using?

I want to verify the DV.

https://s-media-cache-ak0.pinimg.com/236x/66/85/4f/66854f8ab739c32f857a7b6f33f946ce.jpg

Best,

-Slashy

This. Post. Rocks.

Thanks Man The Winston Wolf of KSP problems, awesome!

I don't have the exact info at hand as I'm at work at the mo - but I'll pop it up for sure...

In reality though, even if you did the math and the hardware's got what it takes to get Bob home - I probably haven't got the smarts or pilot skills yet to use it effectively...I've been playing it safe (until now) with my designs by always putting that much more than I need.

...I've got satellites orbiting and SCANsating Kerbin with half a tank of gas in them...

[GoSlash27]

I don't have the exact info at hand as I'm at work at the mo - but I'll pop it up for sure...

In reality though, even if you did the math and the hardware's got what it takes to get Bob home - I probably haven't got the smarts or pilot skills yet to use it effectively...I've been playing it safe (until now) with my designs by always putting that much more than I need.

...I've got satellites orbiting and SCANsating Kerbin with half a tank of gas in them...

Fubarbrickdust,

It'll keep until you get home. If the equipment does have the DV to get him home, I'll walk you through it. If it doesn't... we'll work the problem from there. You've already established that he can reach orbit, so that'll make it a lot easier than rescuing him from the surface.

Don't worry. We'll get him back safe.

Best,

-Slashy

[Vegvisir]

Just be glad you're not using a life support mod Poor Kerbals. Good luck!

[mabarry3]

Don't forget you don't actually need to save Bob's craft to get the science unless your OCD/realism mentality won't let you do that. You can "take" science experiments out of the modules using the Collect Data function while on EVA. Hop over to the rescue ship, and bring all the science with you via Bob over there, and then take the rescue ship home. You don't need to worry about transferring fuel or anything like that, assuming your (second) lander has enough fuel to get home, and you're not then stuck with two unusable crafts on the Munar surface/orbit.

If you can get back into orbit, 4b sounds like your best bet, without actually setting up a docking port and all that and just going straight home from the rescue ship.

Edited October 28, 2015 by mabarry3

[Snark]

On a practical note, a rescue rendezvous is probably easier (especially for a relatively new player) in low munar orbit than on the surface. Doing precision pinpoint landings on the surface is a piloting challenge, and if you end up landing several kilometers away from Bob, he could have a very long and tedious walk.

Orbital rendezvous is also a lot cheaper, since your rescue craft can be smaller and lighter, since it doesn't have to pack all the dV for landing on the Mun and then taking off again, which is a lot (as you have discovered to your sorrow).

One more option to consider: go home without a ship. If you can get Bob into munar orbit, his EVA pack may have enough dV to go all the way home to Kerbin by himself. It's easy to do from Minmus (even from the surface!), not sure about munar orbit since I haven't tried it from there, but I suspect it's not a problem. If you decide to try this route, definitely F5 first! Get into orbit, go EVA, collect the science from the command pod, and go on your way. Aim for a much higher Kerbin periapsis than you would for a ship, since Kerbals are both draggier and less heat-resistant than ships. A periapsis of around 45-50 km should work well. You'll aerobrake with no problem (not even any reentry f/X!), fall out of the sky, and kerplop on the surface (land or sea, doesn't matter) with no ill effects.

Yeah, it's kind of a cheap way out. Just pointing it out as an option.

[Waxing_Kibbous]

I thought saw somewhere that in recent KSP versions the Kerbals will burn up in re-entry

[Shark4558]

You know what you can do? use the same lander that landed in Mun, add a module for remote control, and if you have fuel problems, add a "landing" stage to the lander, that should fix most of the problems, if the lander is in orbit, you would have to send another to meet the first where is Bob ...

[Fubarbrickdust]

Send another manned mission with a spare seat for him. Terminate the other craft after he's home. That's how I handled it. I don't think a Kerbal can reach Mun orbit on their EVA pack, and 50dv left in his lander isn't going to put you there, so I would go with a precision landing 50m from his position (if you're near the equator, that's about 50 arc seconds I think... I use Mech Jeb for precision landings and usually use between 20 and 50 arc seconds delta when landing next to something else).

Danny

Thanks for the advice Danny, but I'm a little confused about the "50 arc seconds" bit...and although it'd be nice the more I think about it, a 'precision landing' where I'm concerned might be a little ambitious He can get into orbit on the fuel he's got though, I've tested it...it's a dangerously low orbit, but an orbit none the less.

On the MechJeb subject - At this stage I'm a little unenthusiastic about using it (not that you're directly suggesting I do) as I feel I'd doing my KSP skill-set a disservice. I'm still a relative noob and don't think it be best. Maybe, way down the road I'll consider it an option...but not before I can do the majority of what MechJeb can on my own wits.

I have switched onto KER - It's awesome. Even then I don't think I'm fully understanding or utilizing all the info that the little PCB/Tape machine or VAC readouts give me...Right now I'm mainly using it for the 'orbital' and 'maneuver' HUDs which have really helped me get a feel for some of the more basic launch and orbital mechanics of the game...and helps cut down on all the map switching, which is nice.

Just be glad you're not using a life support mod Poor Kerbals. Good luck!

This certainly crossed my mind! - As it happens I was (still am) really close to trying out the TAC LS or USI LS mods. Easy does it though, I don't want to swamp myself in too many mods before I get a feel for the core mechanics of the game - softly softly catchy monkey, I guess.

Saying that, any recommendation for one or the other?

Don't forget you don't actually need to save Bob's craft to get the science unless your OCD/realism mentality won't let you do that. You can "take" science experiments out of the modules using the Collect Data function while on EVA. Hop over to the rescue ship, and bring all the science with you via Bob over there, and then take the rescue ship home. You don't need to worry about transferring fuel or anything like that, assuming your (second) lander has enough fuel to get home, and you're not then stuck with two unusable crafts on the Munar surface/orbit.

If you can get back into orbit, 4b sounds like your best bet, without actually setting up a docking port and all that and just going straight home from the rescue ship.

Oh yeah, I'm getting quite familiar with the science farming dance, honed that habit quite early, Thanks though. And yeah, you're right, the more I think about it and listen to the advice I'm getting here it seems like a low orbit rendezvous rescue is the smart move. For sure. It'd be nice to bring the lander home as it holds a certain sentimental value being the 1st vessel to make it and land on another body but essentially that's purely superficial and cosmetic, and would be a bit OCD. The priorities are clear. And the priority is poor old Bob!

On a practical note, a rescue rendezvous is probably easier (especially for a relatively new player) in low munar orbit than on the surface. Doing precision pinpoint landings on the surface is a piloting challenge, and if you end up landing several kilometers away from Bob, he could have a very long and tedious walk.

Orbital rendezvous is also a lot cheaper, since your rescue craft can be smaller and lighter, since it doesn't have to pack all the dV for landing on the Mun and then taking off again, which is a lot (as you have discovered to your sorrow).

One more option to consider: go home without a ship. If you can get Bob into munar orbit, his EVA pack may have enough dV to go all the way home to Kerbin by himself. It's easy to do from Minmus (even from the surface!), not sure about munar orbit since I haven't tried it from there, but I suspect it's not a problem. If you decide to try this route, definitely F5 first! Get into orbit, go EVA, collect the science from the command pod, and go on your way. Aim for a much higher Kerbin periapsis than you would for a ship, since Kerbals are both draggier and less heat-resistant than ships. A periapsis of around 45-50 km should work well. You'll aerobrake with no problem (not even any reentry f/X!), fall out of the sky, and kerplop on the surface (land or sea, doesn't matter) with no ill effects.

Yeah, it's kind of a cheap way out. Just pointing it out as an option.

Ahaa! No way? - I wouldn't of even dreamed of that option being possible...that's too funny Maybe if all else fails I'll give it a go out of desperation...Even if it does fail and he disintegrates in fiery puff of green smoke on re-entry, he'll be forever remembered and revered as a pioneer of experimental space-type-stuff and an alround daredevil legend!

Fubarbrickdust,

It'll keep until you get home. If the equipment does have the DV to get him home, I'll walk you through it. If it doesn't... we'll work the problem from there. You've already established that he can reach orbit, so that'll make it a lot easier than rescuing him from the surface.

Don't worry. We'll get him back safe.

Best,

-Slashy

Dude, that's really cool of you (and the rest of you guys for that matter) for lending your time and consideration to helping out. Thanks man. The feedback and general positive consensus I've heard regarding the KSP Forum community is right on the mark! I'm really chuffed that I discovered this awesome game and joined up to the forum, both.

Relevant info incoming shortly...

Edited October 29, 2015 by Fubarbrickdust

[Fubarbrickdust]

He must be rescued!

I need some vital stats on his ship.

-What is his fuel supply (units of fuel and o2)?

-What is the mass of his ascent module?

-What kind of engine is he using?

I want to verify the DV.

---SNIP---

SO here's the stats:

LF = 48.78

OX = 59.62

Mass = 1.462 / 3.165

Engine: LV-909 'Terrier'

DeltaV Total = 635 m/s (30.6s)

Also, height on the Mun's surface is 1328m if it's of any use

He's up the creek isn't he!?

...tbh, I thought it was a touch more on the LF - I'll test out circularizing the orbit again...maybe that touch I used to get the photovoltics lined up will have pushed it just out of reach:confused:

EDIT: Tested. Orbit is totally do-able with the fuel left over...it's really tight, keep hitting between 12-15k(pe) and 15-20k(pa) but it's repeatable and consistent, so I think it's all good for when the cavalry arrive!

Bob says Hi to everyone btw...he seems to be just fine mooching about on the Mun for the moment - He's re-pitched the 1st off-world flag with a dedication too!

Edited October 29, 2015 by Fubarbrickdust

[GoSlash27]

Fubarbrickdust,

My calculation of DV isn't agreeing with that figure.

What are the two mass figures in your post?

*edit* if your mass at the moment of launch is 3.165t, then your DV figure is accurate enough to bank on and it's not enough to get him home.

And I see that you're no longer on- line, so here's the plan assuming the mass is correct:

1) Put Bob in orbit and make sure his solar panels are deployed. We don't want him on the Munar surface with dead batteries.

2) Next, you already have a ship that can rescue him in orbit. It's the same one that put him on the surface. Just put a probe on it, kick out the crew, and make sure Jeb doesn't sneak aboard when you're not watching.

We're gonna use that to link up with Bob in Munar orbit to bring him home. I'll show you how.

You've got a fully-functioning recovery setup on the ship, I hope? You can get by without the heat shield if you're careful, but you gotta have the chute.

Best,

-Slashy

Edited October 29, 2015 by GoSlash27

[Vegvisir]

This certainly crossed my mind! - As it happens I was (still am) really close to trying out the TAC LS or USI LS mods. Easy does it though, I don't want to swamp myself in too many mods before I get a feel for the core mechanics of the game - softly softly catchy monkey, I guess.

Saying that, any recommendation for one or the other?

I use TAC. I think I like it more than the USI version, though that's just personal preference. I gather USI is maybe "easier"(?) since it has less resources involved. I've yet to run a "big" mission to really grasp the amounts required and gauge the difficulty for myself...so maybe my recommendation doesn't have much worth!!! But, it just fits I think. Build a craft, load the fuel, good to go...or are we? What do my Kerbals eat!? What do they breathe!?

As to your rescue plan, I'll throw my small change in, in support of the low orbit approach. I am perhaps at a similar-ish skill level (?) and I find landing on "target" difficult. Treat it not too differently from the "stock" rescue Kerbal missions, except it's a Mun orbit one, not Kerbin. Getting that fuel balance, though..that's where the likes of Slashy come in I don't plan, measure, math or otherwise. I just stick it together and press spacebar. It totally works

EDIT: Nice pic with the flag btw

[Snark]

I thought saw somewhere that in recent KSP versions the Kerbals will burn up in re-entry

Nope, it works just fine in 1.0.4. Not only can they re-enter, but they can re-enter at coming-home-from-Minmus speeds (low 3000's of m/s). I've done it, it's not a problem at all.

The main thing is to make sure the Pe is pretty high. Most folks who are bringing a ship home will aim for a Pe of 30-35 km. That's too deep for a kerbal, you'll burn up.

To re-enter a kerbal, set your Pe higher, up in the 45-50 km range. You need to do this so they avoid the worst heat of reentry; they can slow down way up high, before they enter the barbecue zone. You can get away with this with a kerbal because they're much lighter and draggier than ships are (that's why your kerbal gets "swept away" if he goes EVA in the upper atmosphere and lets go of the ladder).

It's trivially easy, as long as you keep your Pe high.

(And this is only up to Minmus-return speeds. Come in at interplanetary velocities and you'll fry.)

[Fubarbrickdust]

Fubarbrickdust,

My calculation of DV isn't agreeing with that figure.

What are the two mass figures in your post?

*edit* if your mass at the moment of launch is 3.165t, then your DV figure is accurate enough to bank on and it's not enough to get him home.

And I see that you're no longer on- line, so here's the plan assuming the mass is correct:

1) Put Bob in orbit and make sure his solar panels are deployed. We don't want him on the Munar surface with dead batteries.

2) Next, you already have a ship that can rescue him in orbit. It's the same one that put him on the surface. Just put a probe on it, kick out the crew, and make sure Jeb doesn't sneak aboard when you're not watching.

We're gonna use that to link up with Bob in Munar orbit to bring him home. I'll show you how.

You've got a fully-functioning recovery setup on the ship, I hope? You can get by without the heat shield if you're careful, but you gotta have the chute.

Best,

-Slashy

Thanks Slashy. Already on it! - That's what I was cooking up whilst absent.

Ah yes, apologies if I threw in numbers that might be unnecessary, that's what the little HUD readout for KER was giving me for the 'mass' entry, I wasn't sure which one was the relevant figure...good to now know it's the latter (learned something new there).

This is what's on it's way to the mun to pick him up (below) and it's still got 1,726 m/s left on it. Everything's pretty much as you said - stripped out/bare bones version of the lander, same delivery package. It's 6hrs out from the mun after a much more efficient launch this time (probably due to the much reduced weight too), and so far on track for a perfect equatorial orbit (already got the encounter and adjusted on the an/dn, only need to circularize it on arrival. Set up for a 33km(ap) 28km(pe) if the burn goes as plotted.)

The only thing I've not done is put Bob into orbit yet - would you advise doing that before the rescue boat arrival? I kinda thought (read: assumed) that it'd be prudent to try and time Bobs launch in an attempt to get a rough close encounter going on, then close it in with the rescue vessel? Or would that be making my life more difficult than it has to be? There's still plenty of time to put him up there, and easy enough on the equator, more or less

I use TAC. I think I like it more than the USI version, though that's just personal preference. I gather USI is maybe "easier"(?) since it has less resources involved. I've yet to run a "big" mission to really grasp the amounts required and gauge the difficulty for myself...so maybe my recommendation doesn't have much worth!!! But, it just fits I think. Build a craft, load the fuel, good to go...or are we? What do my Kerbals eat!? What do they breathe!?

As to your rescue plan, I'll throw my small change in, in support of the low orbit approach. I am perhaps at a similar-ish skill level (?) and I find landing on "target" difficult. Treat it not too differently from the "stock" rescue Kerbal missions, except it's a Mun orbit one, not Kerbin. Getting that fuel balance, though..that's where the likes of Slashy come in I don't plan, measure, math or otherwise. I just stick it together and press spacebar. It totally works

EDIT: Nice pic with the flag btw

Cool man, thanks. I'll give it a look in...I was kinda leaning towards TAC as from what I read the Kerbals won't die with the USI one, the just stop functioning until re-supplied...seems not so critical that way. I'm not entirely convinced. some of the other USI mods look awesome though...but I don't feel anywhere near ready for that level stuff yet.

yeah, it seems like that [the rescue plan] is the way it's going. Sensible i think. And still fun - It was probably a very dangerous path going down the 're-fueling lander' mission road....this is way simpler. I might just leave Bob's lander un-terminated and go fix it up much later down the road. Or maybe I'll fly past it Kerbal-years from now, look down and go "Meh! Useless old rust-bucket...I've got new toys now!"

...The flag'll always be there though

EDIT: It's quite late/early here in the UK, 5am, I work evenings so it's cool but I should probably get some shut-eye. Thanks to all for the input so far - I'll shout out and pick it up on the next KSP session (won't be long for sure), but I've got good faith that Bob's gonna make it home!

night chaps,

Fin (Fubarbrickdust)

Edited October 29, 2015 by Fubarbrickdust

[mabarry3]

The dV you still have on the craft alone won't be enough alone to get you into orbit I don't think (unless I'm doing something wrong... I have a miner ship stuck on the Mun I left with about 900 dV and that didn't seem to be enough to get me back to orbit), so I imagine if you want to get Bob back into orbit, you'll need to burn what you have left, hop out before Ap, collect the data you have and then once Ap hits, jump off and continue your burn using EVA fuel to try to make orbit. You'll lose the ship but I'm not sure I see how you could take that back into orbit by itself.

Or maybe I just suck at getting things into orbit

I like the touch on the flag, by the way.

Edited October 29, 2015 by mabarry3

[kreutzkevic]

-SNIP-

There could be a new thread turning up in a few days entitled "I've stranded Bob, and Bill on The Mun...What would you do?"

-SNIP-

I would send over a hab module and call it a base

[technion]

On a practical note, a rescue rendezvous is probably easier (especially for a relatively new player) in low munar orbit than on the surface. Doing precision pinpoint landings on the surface is a piloting challenge, and if you end up landing several kilometers away from Bob, he could have a very long and tedious walk.

Orbital rendezvous is also a lot cheaper, since your rescue craft can be smaller and lighter, since it doesn't have to pack all the dV for landing on the Mun and then taking off again, which is a lot (as you have discovered to your sorrow).

.

I found it easier to land a rover on Eve, drive to a stranded kerbal, pick him up, drive 40km to an ascent vehicle, rendezvous in orbit anf perform a rescue, than to pick up a kerbal from the surface of Duna

[Snark]

The dV you still have on the craft alone won't be enough alone to get you into orbit I don't think (unless I'm doing something wrong... I have a miner ship stuck on the Mun I left with about 900 dV and that didn't seem to be enough to get me back to orbit), so I imagine if you want to get Bob back into orbit, you'll need to burn what you have left, hop out before Ap, collect the data you have and then once Ap hits, jump off and continue your burn using EVA fuel to try to make orbit. You'll lose the ship but I'm not sure I see how you could take that back into orbit by itself.

Or maybe I just suck at getting things into orbit

I like the touch on the flag, by the way.

635 m/s is enough to get into munar orbit... but just barely. It requires an optimal launch profile, and will only get to a very low orbit.

The key to a minimum-dV orbit from the Mun (or any body without an atmosphere) is to minimize gravity losses by going horizontal as soon as humanly (kerbally?) possible. Launch profile is to take off on maximum thrust, then crank it over to near horizontal, with just enough elevation above the horizon to keep from clipping a mountain or crater rim. Burn until your Ap rises up to the lowest possible safe elevation-- say, 8000 m or so-- then coast the long way to Ap and circularize.

In this fashion, the amount of dV to get to orbit is only slightly greater than circular orbital velocity, since you're launching at nearly 100% efficiency: thrusting pure prograde means no cosine losses, and the nearly-horizontal profile minimizes gravity losses.

Note that this assumes that you have a very high local TWR; otherwise, it wouldn't work (lower TWR would require a steeper ascent to keep from lithobraking). That's usually a safe assumption for small landers, since most vacuum worlds are on the small side. But it wouldn't work for, say, Tylo, or for a craft with really low TWR such as a heavily loaded ore tanker.

Edited October 29, 2015 by Snark

[GoSlash27]

Thanks Slashy. Already on it! - That's what I was cooking up whilst absent.

Ah yes, apologies if I threw in numbers that might be unnecessary, that's what the little HUD readout for KER was giving me for the 'mass' entry, I wasn't sure which one was the relevant figure...good to now know it's the latter (learned something new there).

This is what's on it's way to the mun to pick him up (below) and it's still got 1,726 m/s left on it. Everything's pretty much as you said - stripped out/bare bones version of the lander, same delivery package. It's 6hrs out from the mun after a much more efficient launch this time (probably due to the much reduced weight too), and so far on track for a perfect equatorial orbit (already got the encounter and adjusted on the an/dn, only need to circularize it on arrival. Set up for a 33km(ap) 28km(pe) if the burn goes as plotted.)

The only thing I've not done is put Bob into orbit yet - would you advise doing that before the rescue boat arrival? I kinda thought (read: assumed) that it'd be prudent to try and time Bobs launch in an attempt to get a rough close encounter going on, then close it in with the rescue vessel? Or would that be making my life more difficult than it has to be? There's still plenty of time to put him up there, and easy enough on the equator, more or less

Fubarbrickdust,

I would go ahead and orbit him now (make sure he's transferred the science to the pod).

When the rescue ship arrives, you will be able to target him and rendezvous in a single orbit.

1) target him

2) set your closest point of approach to match his orbit

3) retroburn to orbit

4) continue to retroburn while watching his predicted position marker (red arrow pointed up) spin around his orbit.

5) the lower your Ap gets, the slower it will spin. Try to get the marker to line up with your closest point of approach while maintaining a reasonable Ap (still higher than his orbit).

6) if you miss the last encounter, just burn prograde to get it back.

7) orbit once and rendezvous on the next encounter.

Do you know how to rendezvous?

Best,

-Slashy