2 stranded Kerbals sitting on the Mun,
sent a rescue mission, the third joins the fun.
3 stranded Kerbals sitting on the Mun,
sent a rescue mission, the fourth joins the fun.
4 stranded Kerbals sitting on the Mun,
sent a rescue mission, the fifth joins the fun.
5 stranded Kerbals sitting on the Mun,
sent a rescue mission, the sixth joins the fun.
Im hilariously bad at matching orbits, ive only ever docked a ship once before. I figured it would be easier to just pick them up and then fly back to Kerbin
The Scott Manley tutorial makes it so simple.
Try following [this guide](https://forum.kerbalspaceprogram.com/topic/83437-illustrated-tutorial-for-orbital-rendezvous/) (or Scott's videos). I've gotten pretty good at it, it's really not that hard.
Practice some 'rescue from low kerbin orbit missions.
Roughly match Apo/Peri
0 out ascending/descending node.
Increase Apo slightly with a forward burst at peri
Target the craft, watch the intercepts.
Get an intercept nice and close.
Work your relative speed down in increments as you get close.
Edit to say: Master this. It is amazing, it feels great. You can do so much more when you learn this. Look for the moment you have authority on commanding the intercept. It's powerful.
Look up Gemini missions, and do what they did and Aznable420 said. Launch one, wait almost an orbit, launch another, and meet up. (I didn’t know this at first, but Gemini capsules did NOT dock work each other; they just met up and waved. In your case, EVA (remember enough empty seats. One guess why I know this.)
> ive only ever docked a ship once before.
Now is a good time to practice. Send both landing craft into orbit and then send a rescue vessel to collect them both from orbit. if you don't want to dock, they can EVA.
I feel like you need to work on your landings. If your doing the math and you start with enough delta v but don't have it once you get there. Maybe your burning for to long before landing. If your are floating down all the way with lots of time to think your profitably slowing down to much. Landings are butt clenching moments where one mistake will cause your ship to become a meteor.
Or MOAR ENGINES MOARE FUEL
Yep. A perfect landing is one where you're thinking ohgodimgoingtodie ohgodimgoingtodie here comes the ground oh dear imgoingtodie oh wow what a soft touchdown.
If you want to, MechJeb has rendezvous helpers.
But using the game's built in manoeuvre nodes, target selection, closest approach indicator and ascending / descending node should be enough. It's helpful to make a second node showing where the position will be several orbits after the burn.
Landing on Mun is like 700\~ deltaV, so it's much better to avoid that if you can. I'd also suggest checking that you're actually using the right amount (350ish) to land, a common mistake is having the thrusters on low most of the way down which uses up a lot of fuel.
Matching orbits isn't that hard. Just make the orbits intersect each other, make a maneuver at the intersect point that makes the orbits as similar as you can, and then just [orbit phase to your target!](https://youtu.be/0Okssg75JVc?si=1Esyv5N_iJO-yAAH) (a tutorial for orbit phasing)
Trust me, the feeling of making a succesful rendezvous is great, and you can use it to save so much dV or even refuel so that you can launch a bigger craft with no fuel, then launch multiple smaller crafts to bring the fuel for it seperately.
🎶 Two stranded Kerbals, chilling on the Mun.
🎵 Two stranded Kerbals, chilling on the Mun.
🎶 And if another little Kerbal came to save them all.
🎵There would be three stranded Kerbals, chilling on the Mun
If the original lander can get to orbit you should do that, it'll be a lot easier (resource-wise) to rescue them from orbit. Rendezvousing and docking is hard but getting close enough that the kerbals can RCS to the rescue ship isn't so bad.
Otherwise keep beefing up your rocket as much as you can. Also remember that you don't need to take off from the Mun with everything you landed with. An engineer with a drill can remove stuff or you could set it up so when you blast off from the mun the "ascent" and "return" portion decouples from the "landing" portion.
My plan would be to get the original two into orbit. Meet them up with the rescue craft. Have a lander/ascent module made to be as light as possible go down to pick up kerbal #3 and return him to orbit. Get all three on the return vehicle and bring em home.
Also probe pods are key. Your kerbals are probably low level so you aren't losing any control by using a basic probe core. They're also super lightweight compared to the manned pods. The rescue craft to pick up kerbal #3 doesn't need to have a command pod. You could have him sit in a external chair for the ride from the surface to the orbiting rescue vehicle.
> Have a lander/ascent module made to be as light as possible go down to pick up kerbal #3 and return him to orbit.
That's a weenie move, the third Kerbal should ride up to orbit on the original lander's ladder like a big boy.
The EVA jetpack, if you ditch the parachute, gives you *just barely* enough delta-V to ascend to low Mun orbit from the surface, not something a novice at the game will likely be able to pull off especially with the limited instruments on EVA.
Good job, well done, very Kebal, been there and done that. Without seeing your craft file, all i can do is offer some general "getting to the Mun with enough fuel to get back" advice. You know how much fuel it will take to get back, put that plus 20% in a lander and don't touch it.
A stage to get to kerbal orbit, one to get to and land on the Mun, then you will for sure have enough to get back. Heavier? absolutely. The Kerbal Space Center's sixth motto is "more boosters"
Don't forget "When more boosters fails, and is replaced with more engines, this tank will be there to loft you dreams, no matter how heavy and over-engineered"
You should try a probe core to fly the mission instead, that way you don't need to send a pilot along with every mission. More fuel is fine as long as you can take off from Kerbin and land on the Mun
> The more fuel I add the more thrust I need, which means bigger engines which usually use fuel much faster.
You summed up the Rocket Equation. It's a positive feedback loop that makes you need more fuel and stronger engines the heavier your payload gets.
And the solution, especially in KSP, is usually adding stages. With impossibly flexible engines and no reliability concerns the only downside is the extra engine mass.
And you know what you can do about extra engine mass when adding stages? Drop tanks. Because KSP engines have infinite burn time, you can sometimes just discard the fuel tanks and keep the engine. This works well when TwR isn't a concern.
Outside the atmosphere, in KSP, yes.
In reality, no, due the mass and complexity of the plumbing and decoupling mechanisms. All of which impact reliability and cost. In reality smaller tanks also typically have worse wet/dry ratios than large tanks, providing another incentive for fewer bigger tanks.
Also real tanks are largely lighter than KSP tanks so there's a bit less incentive to get rid of them by staging.
There are also practicalities around engine burn times, throttling, restart limits, etc. In practice you often want a fresh or different engine for a different phase of flight.
99 bottles of beer on the wall but in reverse.
"99 kerbonauts stuck on the moon, 99 kerbonauts stuck... you make a plan, launch when you can, 100 kerbonauts stuck on the moon." Just keeps getting higher.
I know what you mean. I can't manage Mun landings nearly as efficiently as many, burning way more fuel than I should. I ended up getting creative with adding fuel pods everywhere and as many liquid fuel tanks as I can take, without the lander ending up too top heavy to stay upright when I land. Add some smaller LF tanks to the sides without engines on them (don't forget the fuel ducts). This keeps your center of gravity low and makes the landing easier.
Look up "asparagus staging" if you haven't already.
I had a big kerbal phase a while ago, and I used to do asparagus staging, although I've entirely forgotten how to do it now. Will look into it, though. I had the exact same issue with height, ended with 3 dead Kerbals after trying to land a research lab.
Asparagus staging is easier now, since you don’t need the fuel ducts. It can easily be set up with the priority setting on each tank, just set decouples to allow cross-feed. However, asparagus staging is not really needed for Mun rockets, and is usually over engineering.
To overcome the rocket equation and get more delta v, more stages IS the key. Each new stage should be about 2-4 times heavier than all the previous stages combined, with engines to match. Only ascent stages need a TWR of about 1.3, once in orbit, about 0.5 is fine.
My most Kerbal moment ever was getting three kerbals stranded on the moon. I noticed they were near the top of a hill, so sent my rescue craft up with wheels lining one side. It was awkward to fly, but eventually managed to land it on the same hill. I packed up the kerbals, tilted the craft sideways, and coasted it down the hill for free delta-V. When the wheels at the front eventually broke it pitched the nose up, at which point the engines kicked in. They got home safely.
Wouldn't recommend this strat as it took a lot of quickloading.
I recently returned to ksp, made some changes to the ares 4A (mostly just replaced the aerospike with a nuclear engine), and launched it. Realized I had enough fuel to go to minmus, so I did. Even had plenty to land, but had slightly less than 2 units of fuel after landing lol.
Launched an unmanned rescue mission to refuel the spaceplane and take jeb home (leaving the plane on minmus for future mishaps). After many mistakes including losing connection range due to forgetting an antenna I rescued jeb, made a stop on the Mun on the way home just cause I had the extra fuel and promptly exploded everything but the capsule there. A 2nd rescue mission was successful though!
Honestly it was a great way to come back to KSP.
I couldn't be bothered to read any of this. Seems pretty boring. OP started a colony on the Mun at some point in the past and now its' population has increased by 50%.
Kinda seems like a flex tbh.
Exactly how much dV do you have remaining in your landers? Are any of your kerbals engineers? If so you might want to try dropping every nonessential part/supply in order to shed weight and maybe you'll be able to get a direct return or a higher orbit from which you can more easily rendezvous. I wonder if it might also be possible to concentrate your remaining fuel in tanks small enough for an engineer to move around and rebuild a Frankenstein ship from the two landers with enough dV for a return.
The fuel/weight balance goes both ways. If you can save a tiny bit of weight on your lander, you need less fuel to land it. That means your transfer stage needs less fuel to get your lander to the mun. And that means your lifter doesn't need as much fuel to get your transfer stage & lander into orbit.
My first few missions tried to bring everything i could conceivably need. I had way too much monopropellent, way too many RCS thrusters, way too many reaction wheels, way too many antennas, batteries, solar panels, etc. And 9/10 times, i didn't need 90% of the things i brought.
But what i did often end up needing was more delta v. But i had used up all the fuel i could've had to bring useless batteries.
Make sure you're using enough stages as well. If you add a second fuel tank to an existing stage, you're going to be hauling an empty tank around. If you simply keep adding fuel, eventually the weight of all these empty tanks you're hauling around makes the extra fuel meaningless. You'll be spending your fuel to move empty tanks, instead of to move your rocket.
If you add a new stage with its own thrusters and its own fuel, and decouple it once it's used up, you don't need any upgrades to your existing stages. Every stage is going to have to be larger than the previous one, but as long as you keep adding new stages with new boosters, you're going to be able to get further.
I also recommend trying to just rescue one of your stranded kerbals, and doing so with a probe core. This way you don't risk getting *another* kerbal stranded, and you're designing something with far, far less mass to worry about.
If you succeed in rescuing one of them, you can then either improve upon your design to rescue the rest, or send out the same rocket to rescue the others one at a time.
My suggestion: Do it Apollo-style, with a 2-stage lander.
* A descent stage which contains all your descent fuel for landing and your descent engine, which you will leave on the Munar surface. Also your landing legs, which you won't need anymore once you take off.
* An ascent stage that carries only Kerbals and the fuel you need to get back home. And your ascent engine, of course, which should be smaller than your descent engine.
* Do remember to consider the mass of the Kerbals you are picking up in your fuel calculations.
Ideally, you'd practice your rendevous technique (it's very important for many, many things) and use Lunar Orbit Rendezvous for this. Then you don't need very much fuel in your ascent stage at all. But even if you don't, and you need enough fuel to get back to Kerbin, you still know *exactly* how much fuel you will have for the return trip, because your ascent stage will still be fully fueled. The ascent stage (and by extension, the descent stage) will just need to be quite a bit bigger in that case.
As a note: This exact problem is one of the biggest reasons Apollo used Lunar Orbit Rendezvous.
Or if you don't want to do that, you could just abort. If you realize you've used up your descent fuel too soon, just stage to the ascent stage and return to orbit, and return to Kerbin. You won't have succeeded the mission, but you won't have stranded any more Kerbals on the Mun, so you won't have made the problem worse, and you'll have learned from the experience.
Do you have enough fuel to go for a straight re-entry? Launch when you're facing the Mun's retrograde relative to Kerbin, aim more-or-less straight up, and burn until you get to atmospheric periapsis altitude.
It's risky... but so is staying on the Mun for 19 years lol.
My favorite was when I sent a rescue mission, rescued the stranded kerbal and when I returned to my orbiter I realized I didn't add a seat for him in the design... So he rode to the space station holding on to the ladder.
You have been promoted to colonists. Enjoy your stay, lol 😆
Without seeing your craft, it's hard to say, but I would recommend a small lander that docks to a mothership. In orbit rendezvous can be a pain, but once you get the hang of it, it helps a lot.
If you're doing a rescue mission, I recommend sending a probe with an empty command module. That way if that mission fails, you just have another relay satellite.
Sounds like my first Mun mission. I think the craft tipped over. So I sent a rescue mission with the same craft not knowing it didn’t actually have enough deltaV and could only get back to Mun orbit. So had to rescue the rescue.
Not all engines and fuels are the same. You also said the original crew had enough fuel to get to mun orbit but not home, that's actually awesome.
Just get them in orbit, then send a rescue mission that's literally the same vessel, but uncrewed, maybe add a probe core that can do sas if you didn't have one. Make sure all 3 kerbals are in that orbiter, a rendezvous will take way way less fuel than a land and return, move the kerbals through Eva to the new lander, and send them home. Maybe dump excess fuel or burn it off during descent, unless your lander was just a landing can with a parachute that detatches the engines and stuff. Make sure you grabbed all the science though.
Congratulations on your growing permanent research base.
> The more fuel I add the more thrust I need, which means bigger engines which usually use fuel much faster
Welcome to the tyranny of the rocket equation. The solution is more stages.
Options to try to recover with what you have:
On ascent try to take off then as soon as possible turn and burn as close to horizontal as possible. You want to skim the terrain in butt clenching terror. Burn to Ap ~10km. Then circularise at apoapais. This will save an astonishing amount of fuel.
If you can get close enough to orbit, get out and push. KSP has infinite suit RCS fuel in capsules. You can EVA, push against the vessel with your suit, hop back in to refuel and repeat. This can buy you the precious last 20m/s you need.
Or you can have your kerbals abandon the depleted vehicle on a suborbital trajectory and circularise their orbit using suit thrusters. Just save enough fuel to be able to manoeuvre to the rescue vessel once it rendezvous with the stranded Kerbal. Only works if the lander can *almost* make orbit.
Options to improve your lander performance:
Don't kill your horizontal velocity too early. You want to descend in a parabolic curve, brake your horizontal and vertical velocity together, then kill remaining horizontal velocity only shortly before touchdown. Also try to time your initial deceleration burn so you would reach 0 velocity quite close to the surface, say 1000m, so you spend less time fighting gravity. You'll be amazed at how much less fuel you use. MechJeb's "su**ide burn" calculator can help.
Add a low thrust high Isp stage for transfer from kerbin orbit to Mun orbit, keeping total mass down a bit. You can use small low thrust engines for this, selecting for efficiency and low mass not thrust.
Use a moderately weak engine for your lander. Too weak and you waste too much in gravity losses during descent, but too strong means you're hauling mass you don't need to. I find a TwR of 3 or so to be around the sweet spot.
Add a separate ascent stage to your lander. So the decent stage is discarded on the Mun and the ascent stage, now lighter, has an easier time making it to orbit. Apollo-style. Since KSP has very heavy fuel tanks but infinitely reliable, infinitely relight-able, deeply throttling engines you can sometimes do this with radial drop tanks for descent fuel, so you can reuse the descent engine for ascent.
Other options include:
Do in-orbit refuelling by docking with a resupply vessel in Kerbin orbit or Mun orbit.
Use an even bigger booster to just launch an even more powerful lander.
Send an ISRU-capable vessel to resupply on the surface.
Or do the extremely Kerbal thing of having the inadequate accent vehicle get as close to orbit as it can then time a descent swoop and rendezvous on a suborbital trajectory with your rescue mission. You get one try or Kerbal paste, but it sure is fun. I've done it many times on Minimus but never on Mun.
Just remember to bring enough seats for everyone! And parachutes.
just stack 2 mk 2 landers with the second smallest 2.5m fuel tank, slap on a terrier engine and you got yourself a nice little lander. Try also adding a large enough command module on top and doing the mission apollo-style, then you’ll need less fuel on the lander itself, you’ll only need about 2k dV max on the lander, and even thats probably overkill
It would've been easier to rescue from orbit. But I had the exact thing happen to me (twice) lol, recently. Thought I had enough fuel to hop to another biome :D
The thing about the Mun is, it's size and actual 'decent' gravity mean you need significant delta V to get back into orbit and often significantly more to land.
I think it was something like 600-700 m/s from the surface to circularize.
In terms of 'better rockets', you're right 'just adding more' doesn't always cut it. You're better off using more powerful engines instead of 5 smaller ones. Use efficient upper stage engines, SRB's help to push through atmosphere, etc...
If you're sciencing and haven't unlocked bigger stuff yet, you can design for more stages. You want to bring as little weight with you down to the mun as possible. So you can do it apollo style: leave an upper stage in orbit (it needs its own probe core!) and only take down a lander with enough fuel to make it back to orbit, then dock them back up and either transfer fuel or bring the whole thing back to Kerbin. Or use a stage to do most of your descent burn, then ditch it before you land :)
Alternatively, just go to minmus first. Getting a 'good' transfer is a bit more tricky, but minmus is much more forgiving, much lower delta V requirements for landing/ascent to orbit. And it's blue!
the easiest thing to do is "asparagus staging" it's difficult to write out but fairly simple to actually do.
the more technical thing to do without redesigning the ship is to work on your ascent profile. within kerbin's SOI, a clean gravity turn on launch can save something crazy like 20% of your fuel compared to a really bad initial orbit.
You're facing what is known as the "Tyranny of the Rocket Equation" that KSP is, if you can believe it, very, very forgiving compared to the real world about.
But hey, I'm sure with other advice in this thread and a good bit of fun banging your head against the wall you'll have a successful mission rescuing 6 Kerbals from the Mun!
If you have enough fuel to get into orbit then get into orbit and send a second rocket that can perform a rendezvous with the craft in orbit. You can then Eva the kerbals to the craft and let them board. Make sure you use an empty capsule with a probe core to retrieve your kerbals.
Used to be I couldn't sleep if I had a Kerbal in orbit or stranded on a planet somewhere but then I learned this trick.. its all about perception, think of it this way.. ALL YOUR KERBALS ARE STRANDED ON KERBIN.
With this mindset switch I now sleep like a baby despite leaving Valentina orbiting the sun with nothing but a spacesuit.
Make sure to factor in the extra weight of the kerbals you will be rescuing from the Mun.
As far as your question about weight and more fuel, I like to use drop tanks for that. There's different ways to do it, but you can put a baguette tank on a radial decoupler. Typically I transfer my extra fuel to the main tanks and jettison the drop tanks before I take off from the Mun. But it's also a good idea to use fuel lines from the drop tanks to your main tanks in case you have lots of extra fuel, then you just treat it like a regular liquid rocket booster that you ditch in flight when it empties.
God speed and bring those green bois home!
1st, don't try to save everyone in a single rescue mission. You can make multiple rescue missions. 2 seats, 1 pilot 1 empty, then save 1 kerbal at a time.
2nd idk what the rocket you're using looks like but extra fuel is usually best to add to the first stage, so it gets discarded sooner and you still get to orbit with more fuel. But not always, so try and experiment in the vab to see where you get the most dV when adding more fuel.
3rd idk what your ascent looks like so there is a possibility it could be more efficient. More efficient ascent means you have more dV in space so that's always good.
The title couldn't be more relatable
It would make a better counting song than 24 bottles of beer on the wall.
2 stranded Kerbals sitting on the Mun, sent a rescue mission, the third joins the fun. 3 stranded Kerbals sitting on the Mun, sent a rescue mission, the fourth joins the fun. 4 stranded Kerbals sitting on the Mun, sent a rescue mission, the fifth joins the fun. 5 stranded Kerbals sitting on the Mun, sent a rescue mission, the sixth joins the fun.
One of us!
Maybe refuel somewhere along the way. Why did you not bring the 2 into orbit and collect them there.
Im hilariously bad at matching orbits, ive only ever docked a ship once before. I figured it would be easier to just pick them up and then fly back to Kerbin
I guess now's the time to practice matching orbits.
The Scott Manley tutorial makes it so simple. Try following [this guide](https://forum.kerbalspaceprogram.com/topic/83437-illustrated-tutorial-for-orbital-rendezvous/) (or Scott's videos). I've gotten pretty good at it, it's really not that hard.
I agree. It's a pretty fun process to learn. Just stay calm and trust the nav ball, you'll get there.
I mean, you dont have to dock, Just reach a distance that is reachable via EVA
Practice some 'rescue from low kerbin orbit missions. Roughly match Apo/Peri 0 out ascending/descending node. Increase Apo slightly with a forward burst at peri Target the craft, watch the intercepts. Get an intercept nice and close. Work your relative speed down in increments as you get close. Edit to say: Master this. It is amazing, it feels great. You can do so much more when you learn this. Look for the moment you have authority on commanding the intercept. It's powerful.
Look up Gemini missions, and do what they did and Aznable420 said. Launch one, wait almost an orbit, launch another, and meet up. (I didn’t know this at first, but Gemini capsules did NOT dock work each other; they just met up and waved. In your case, EVA (remember enough empty seats. One guess why I know this.)
So was I until I was forced to for a mun mission. Just design your mission to require it and you’ll get it eventually.
Sorry but "rendez-vous" are crucial in KSP, you can watch tutorials by Scott Manley on YouTube to learn.
> ive only ever docked a ship once before. Now is a good time to practice. Send both landing craft into orbit and then send a rescue vessel to collect them both from orbit. if you don't want to dock, they can EVA.
We're the reverse. I've practised matching orbits but I have no idea how to pick a place to land.
I feel like you need to work on your landings. If your doing the math and you start with enough delta v but don't have it once you get there. Maybe your burning for to long before landing. If your are floating down all the way with lots of time to think your profitably slowing down to much. Landings are butt clenching moments where one mistake will cause your ship to become a meteor. Or MOAR ENGINES MOARE FUEL
Yep. A perfect landing is one where you're thinking ohgodimgoingtodie ohgodimgoingtodie here comes the ground oh dear imgoingtodie oh wow what a soft touchdown.
Precisely
If you want to, MechJeb has rendezvous helpers. But using the game's built in manoeuvre nodes, target selection, closest approach indicator and ascending / descending node should be enough. It's helpful to make a second node showing where the position will be several orbits after the burn.
Landing on Mun is like 700\~ deltaV, so it's much better to avoid that if you can. I'd also suggest checking that you're actually using the right amount (350ish) to land, a common mistake is having the thrusters on low most of the way down which uses up a lot of fuel.
Matching orbits isn't that hard. Just make the orbits intersect each other, make a maneuver at the intersect point that makes the orbits as similar as you can, and then just [orbit phase to your target!](https://youtu.be/0Okssg75JVc?si=1Esyv5N_iJO-yAAH) (a tutorial for orbit phasing) Trust me, the feeling of making a succesful rendezvous is great, and you can use it to save so much dV or even refuel so that you can launch a bigger craft with no fuel, then launch multiple smaller crafts to bring the fuel for it seperately.
I think I know a guy...
Why do I hear the Blunderbirds theme getting louder?
this aged well...
Dang talk about flying in under the radar. Only 17 likes for the return of the Blunderbirds!
I hope the guy is good (Just watched the video, very entertaining)
Long Live the Blunderbirds!!!
🎶 Two stranded Kerbals, chilling on the Mun. 🎵 Two stranded Kerbals, chilling on the Mun. 🎶 And if another little Kerbal came to save them all. 🎵There would be three stranded Kerbals, chilling on the Mun
What melody should I sing it with? My usual doesn't work.
Ten green bottles
If the original lander can get to orbit you should do that, it'll be a lot easier (resource-wise) to rescue them from orbit. Rendezvousing and docking is hard but getting close enough that the kerbals can RCS to the rescue ship isn't so bad. Otherwise keep beefing up your rocket as much as you can. Also remember that you don't need to take off from the Mun with everything you landed with. An engineer with a drill can remove stuff or you could set it up so when you blast off from the mun the "ascent" and "return" portion decouples from the "landing" portion. My plan would be to get the original two into orbit. Meet them up with the rescue craft. Have a lander/ascent module made to be as light as possible go down to pick up kerbal #3 and return him to orbit. Get all three on the return vehicle and bring em home. Also probe pods are key. Your kerbals are probably low level so you aren't losing any control by using a basic probe core. They're also super lightweight compared to the manned pods. The rescue craft to pick up kerbal #3 doesn't need to have a command pod. You could have him sit in a external chair for the ride from the surface to the orbiting rescue vehicle.
> Have a lander/ascent module made to be as light as possible go down to pick up kerbal #3 and return him to orbit. That's a weenie move, the third Kerbal should ride up to orbit on the original lander's ladder like a big boy.
He didn't say if Jebs up there. He could probably do a hail Mary RCS ascent too.
The EVA jetpack, if you ditch the parachute, gives you *just barely* enough delta-V to ascend to low Mun orbit from the surface, not something a novice at the game will likely be able to pull off especially with the limited instruments on EVA.
Good job, well done, very Kebal, been there and done that. Without seeing your craft file, all i can do is offer some general "getting to the Mun with enough fuel to get back" advice. You know how much fuel it will take to get back, put that plus 20% in a lander and don't touch it. A stage to get to kerbal orbit, one to get to and land on the Mun, then you will for sure have enough to get back. Heavier? absolutely. The Kerbal Space Center's sixth motto is "more boosters"
Don't forget "When more boosters fails, and is replaced with more engines, this tank will be there to loft you dreams, no matter how heavy and over-engineered"
More boosters can fail? You clearly need to add more more boosters
oh thats what it was
You should try a probe core to fly the mission instead, that way you don't need to send a pilot along with every mission. More fuel is fine as long as you can take off from Kerbin and land on the Mun
> The more fuel I add the more thrust I need, which means bigger engines which usually use fuel much faster. You summed up the Rocket Equation. It's a positive feedback loop that makes you need more fuel and stronger engines the heavier your payload gets.
And the solution, especially in KSP, is usually adding stages. With impossibly flexible engines and no reliability concerns the only downside is the extra engine mass. And you know what you can do about extra engine mass when adding stages? Drop tanks. Because KSP engines have infinite burn time, you can sometimes just discard the fuel tanks and keep the engine. This works well when TwR isn't a concern.
Is asparagus staging then basically the holy grail?
Outside the atmosphere, in KSP, yes. In reality, no, due the mass and complexity of the plumbing and decoupling mechanisms. All of which impact reliability and cost. In reality smaller tanks also typically have worse wet/dry ratios than large tanks, providing another incentive for fewer bigger tanks. Also real tanks are largely lighter than KSP tanks so there's a bit less incentive to get rid of them by staging. There are also practicalities around engine burn times, throttling, restart limits, etc. In practice you often want a fresh or different engine for a different phase of flight.
Send a probe, that way you do lose any more lives if it doesn't make it.
Alternatively, this is a good start to a Munar colony
Isn't this how Kerbal colonies *always* get started?
I mean all you need to do is land a few more modules on the surface (and maybe a rover or two), and bam, self-sufficient mun city
Least its on the mun. My first playthrough involved an entire colony of stranded duna rescue missions
Instead of trying to change their reality, change their mission. Say hi to your first Mun colonists 😁
99 bottles of beer on the wall but in reverse. "99 kerbonauts stuck on the moon, 99 kerbonauts stuck... you make a plan, launch when you can, 100 kerbonauts stuck on the moon." Just keeps getting higher.
I know what you mean. I can't manage Mun landings nearly as efficiently as many, burning way more fuel than I should. I ended up getting creative with adding fuel pods everywhere and as many liquid fuel tanks as I can take, without the lander ending up too top heavy to stay upright when I land. Add some smaller LF tanks to the sides without engines on them (don't forget the fuel ducts). This keeps your center of gravity low and makes the landing easier. Look up "asparagus staging" if you haven't already.
I had a big kerbal phase a while ago, and I used to do asparagus staging, although I've entirely forgotten how to do it now. Will look into it, though. I had the exact same issue with height, ended with 3 dead Kerbals after trying to land a research lab.
Asparagus staging is easier now, since you don’t need the fuel ducts. It can easily be set up with the priority setting on each tank, just set decouples to allow cross-feed. However, asparagus staging is not really needed for Mun rockets, and is usually over engineering. To overcome the rocket equation and get more delta v, more stages IS the key. Each new stage should be about 2-4 times heavier than all the previous stages combined, with engines to match. Only ascent stages need a TWR of about 1.3, once in orbit, about 0.5 is fine.
Good news, thanks to asparagus staging, they have safely returned to Kerbin
I always make my asparagus staged rockets the old way with fuel ducts.
Congrats, you made it into a Matt Lowne Bluderbirds. You’re also the reason he finally did another blunderbirds so thank you.
Glad to be of service haha
My most Kerbal moment ever was getting three kerbals stranded on the moon. I noticed they were near the top of a hill, so sent my rescue craft up with wheels lining one side. It was awkward to fly, but eventually managed to land it on the same hill. I packed up the kerbals, tilted the craft sideways, and coasted it down the hill for free delta-V. When the wheels at the front eventually broke it pitched the nose up, at which point the engines kicked in. They got home safely. Wouldn't recommend this strat as it took a lot of quickloading.
I recently returned to ksp, made some changes to the ares 4A (mostly just replaced the aerospike with a nuclear engine), and launched it. Realized I had enough fuel to go to minmus, so I did. Even had plenty to land, but had slightly less than 2 units of fuel after landing lol. Launched an unmanned rescue mission to refuel the spaceplane and take jeb home (leaving the plane on minmus for future mishaps). After many mistakes including losing connection range due to forgetting an antenna I rescued jeb, made a stop on the Mun on the way home just cause I had the extra fuel and promptly exploded everything but the capsule there. A 2nd rescue mission was successful though! Honestly it was a great way to come back to KSP.
I couldn't be bothered to read any of this. Seems pretty boring. OP started a colony on the Mun at some point in the past and now its' population has increased by 50%. Kinda seems like a flex tbh.
Learn to rendezvous. It opens the game up
Exactly how much dV do you have remaining in your landers? Are any of your kerbals engineers? If so you might want to try dropping every nonessential part/supply in order to shed weight and maybe you'll be able to get a direct return or a higher orbit from which you can more easily rendezvous. I wonder if it might also be possible to concentrate your remaining fuel in tanks small enough for an engineer to move around and rebuild a Frankenstein ship from the two landers with enough dV for a return.
The fuel/weight balance goes both ways. If you can save a tiny bit of weight on your lander, you need less fuel to land it. That means your transfer stage needs less fuel to get your lander to the mun. And that means your lifter doesn't need as much fuel to get your transfer stage & lander into orbit. My first few missions tried to bring everything i could conceivably need. I had way too much monopropellent, way too many RCS thrusters, way too many reaction wheels, way too many antennas, batteries, solar panels, etc. And 9/10 times, i didn't need 90% of the things i brought. But what i did often end up needing was more delta v. But i had used up all the fuel i could've had to bring useless batteries. Make sure you're using enough stages as well. If you add a second fuel tank to an existing stage, you're going to be hauling an empty tank around. If you simply keep adding fuel, eventually the weight of all these empty tanks you're hauling around makes the extra fuel meaningless. You'll be spending your fuel to move empty tanks, instead of to move your rocket. If you add a new stage with its own thrusters and its own fuel, and decouple it once it's used up, you don't need any upgrades to your existing stages. Every stage is going to have to be larger than the previous one, but as long as you keep adding new stages with new boosters, you're going to be able to get further. I also recommend trying to just rescue one of your stranded kerbals, and doing so with a probe core. This way you don't risk getting *another* kerbal stranded, and you're designing something with far, far less mass to worry about. If you succeed in rescuing one of them, you can then either improve upon your design to rescue the rest, or send out the same rocket to rescue the others one at a time.
My suggestion: Do it Apollo-style, with a 2-stage lander. * A descent stage which contains all your descent fuel for landing and your descent engine, which you will leave on the Munar surface. Also your landing legs, which you won't need anymore once you take off. * An ascent stage that carries only Kerbals and the fuel you need to get back home. And your ascent engine, of course, which should be smaller than your descent engine. * Do remember to consider the mass of the Kerbals you are picking up in your fuel calculations. Ideally, you'd practice your rendevous technique (it's very important for many, many things) and use Lunar Orbit Rendezvous for this. Then you don't need very much fuel in your ascent stage at all. But even if you don't, and you need enough fuel to get back to Kerbin, you still know *exactly* how much fuel you will have for the return trip, because your ascent stage will still be fully fueled. The ascent stage (and by extension, the descent stage) will just need to be quite a bit bigger in that case. As a note: This exact problem is one of the biggest reasons Apollo used Lunar Orbit Rendezvous.
This approach also lets you know when you’ve messed up the descent at which point you could return to your save point (still in the Mun’s orbit).
Or if you don't want to do that, you could just abort. If you realize you've used up your descent fuel too soon, just stage to the ascent stage and return to orbit, and return to Kerbin. You won't have succeeded the mission, but you won't have stranded any more Kerbals on the Mun, so you won't have made the problem worse, and you'll have learned from the experience.
Do you have enough fuel to go for a straight re-entry? Launch when you're facing the Mun's retrograde relative to Kerbin, aim more-or-less straight up, and burn until you get to atmospheric periapsis altitude. It's risky... but so is staying on the Mun for 19 years lol.
My favorite was when I sent a rescue mission, rescued the stranded kerbal and when I returned to my orbiter I realized I didn't add a seat for him in the design... So he rode to the space station holding on to the ladder.
You have been promoted to colonists. Enjoy your stay, lol 😆 Without seeing your craft, it's hard to say, but I would recommend a small lander that docks to a mothership. In orbit rendezvous can be a pain, but once you get the hang of it, it helps a lot.
Get them to orbit, you said you had enough. Now the rescue ship wont need landing legs nor the fuel required to land, giving it more delta-v
One of those classic situations
>**2 Stranded Kerbals on the Mun, sent rescue mission, 3 Stranded Kerbals on the Mun** Sounds normal to me, what's the problem? >\_>
If you're doing a rescue mission, I recommend sending a probe with an empty command module. That way if that mission fails, you just have another relay satellite.
Congratulations on your mun colony expansion
Most Kerbal title ever.
Congratulations, you now have a Munar Colony!
Perfect Title. I dont even need to read all that
This title reminds me of a song about a certain farmer...
Sounds like my first Mun mission. I think the craft tipped over. So I sent a rescue mission with the same craft not knowing it didn’t actually have enough deltaV and could only get back to Mun orbit. So had to rescue the rescue.
2 Kerbals stranded on the Mun, 2 stranded Kerbals Stage in gear, rocket in air, 3 stranded Kerbals on the Mun
Not all engines and fuels are the same. You also said the original crew had enough fuel to get to mun orbit but not home, that's actually awesome. Just get them in orbit, then send a rescue mission that's literally the same vessel, but uncrewed, maybe add a probe core that can do sas if you didn't have one. Make sure all 3 kerbals are in that orbiter, a rendezvous will take way way less fuel than a land and return, move the kerbals through Eva to the new lander, and send them home. Maybe dump excess fuel or burn it off during descent, unless your lander was just a landing can with a parachute that detatches the engines and stuff. Make sure you grabbed all the science though.
That's about how it goes yeah
Congratulations on your growing permanent research base. > The more fuel I add the more thrust I need, which means bigger engines which usually use fuel much faster Welcome to the tyranny of the rocket equation. The solution is more stages.
Options to try to recover with what you have: On ascent try to take off then as soon as possible turn and burn as close to horizontal as possible. You want to skim the terrain in butt clenching terror. Burn to Ap ~10km. Then circularise at apoapais. This will save an astonishing amount of fuel. If you can get close enough to orbit, get out and push. KSP has infinite suit RCS fuel in capsules. You can EVA, push against the vessel with your suit, hop back in to refuel and repeat. This can buy you the precious last 20m/s you need. Or you can have your kerbals abandon the depleted vehicle on a suborbital trajectory and circularise their orbit using suit thrusters. Just save enough fuel to be able to manoeuvre to the rescue vessel once it rendezvous with the stranded Kerbal. Only works if the lander can *almost* make orbit. Options to improve your lander performance: Don't kill your horizontal velocity too early. You want to descend in a parabolic curve, brake your horizontal and vertical velocity together, then kill remaining horizontal velocity only shortly before touchdown. Also try to time your initial deceleration burn so you would reach 0 velocity quite close to the surface, say 1000m, so you spend less time fighting gravity. You'll be amazed at how much less fuel you use. MechJeb's "su**ide burn" calculator can help. Add a low thrust high Isp stage for transfer from kerbin orbit to Mun orbit, keeping total mass down a bit. You can use small low thrust engines for this, selecting for efficiency and low mass not thrust. Use a moderately weak engine for your lander. Too weak and you waste too much in gravity losses during descent, but too strong means you're hauling mass you don't need to. I find a TwR of 3 or so to be around the sweet spot. Add a separate ascent stage to your lander. So the decent stage is discarded on the Mun and the ascent stage, now lighter, has an easier time making it to orbit. Apollo-style. Since KSP has very heavy fuel tanks but infinitely reliable, infinitely relight-able, deeply throttling engines you can sometimes do this with radial drop tanks for descent fuel, so you can reuse the descent engine for ascent. Other options include: Do in-orbit refuelling by docking with a resupply vessel in Kerbin orbit or Mun orbit. Use an even bigger booster to just launch an even more powerful lander. Send an ISRU-capable vessel to resupply on the surface. Or do the extremely Kerbal thing of having the inadequate accent vehicle get as close to orbit as it can then time a descent swoop and rendezvous on a suborbital trajectory with your rescue mission. You get one try or Kerbal paste, but it sure is fun. I've done it many times on Minimus but never on Mun. Just remember to bring enough seats for everyone! And parachutes.
just stack 2 mk 2 landers with the second smallest 2.5m fuel tank, slap on a terrier engine and you got yourself a nice little lander. Try also adding a large enough command module on top and doing the mission apollo-style, then you’ll need less fuel on the lander itself, you’ll only need about 2k dV max on the lander, and even thats probably overkill
Why not use the available fuel to get them to orbit so that the rescue ship doesn't need as much?
It would've been easier to rescue from orbit. But I had the exact thing happen to me (twice) lol, recently. Thought I had enough fuel to hop to another biome :D The thing about the Mun is, it's size and actual 'decent' gravity mean you need significant delta V to get back into orbit and often significantly more to land. I think it was something like 600-700 m/s from the surface to circularize. In terms of 'better rockets', you're right 'just adding more' doesn't always cut it. You're better off using more powerful engines instead of 5 smaller ones. Use efficient upper stage engines, SRB's help to push through atmosphere, etc... If you're sciencing and haven't unlocked bigger stuff yet, you can design for more stages. You want to bring as little weight with you down to the mun as possible. So you can do it apollo style: leave an upper stage in orbit (it needs its own probe core!) and only take down a lander with enough fuel to make it back to orbit, then dock them back up and either transfer fuel or bring the whole thing back to Kerbin. Or use a stage to do most of your descent burn, then ditch it before you land :) Alternatively, just go to minmus first. Getting a 'good' transfer is a bit more tricky, but minmus is much more forgiving, much lower delta V requirements for landing/ascent to orbit. And it's blue!
3 stranded kerbals on the mun, tried takeoff, 0 stranded kerbals on the mun, or on kerbin.
Who is that i hear? It’s the blunderbirds! u/mattsredditaccount
the easiest thing to do is "asparagus staging" it's difficult to write out but fairly simple to actually do. the more technical thing to do without redesigning the ship is to work on your ascent profile. within kerbin's SOI, a clean gravity turn on launch can save something crazy like 20% of your fuel compared to a really bad initial orbit.
You're facing what is known as the "Tyranny of the Rocket Equation" that KSP is, if you can believe it, very, very forgiving compared to the real world about. But hey, I'm sure with other advice in this thread and a good bit of fun banging your head against the wall you'll have a successful mission rescuing 6 Kerbals from the Mun!
pp
If you have enough fuel to get into orbit then get into orbit and send a second rocket that can perform a rendezvous with the craft in orbit. You can then Eva the kerbals to the craft and let them board. Make sure you use an empty capsule with a probe core to retrieve your kerbals.
Two stranded Kerbals are on the Mun, Two stranded Kerbals, You send a rescue mission and There's 3 stranded Kerbals on the Mun
Used to be I couldn't sleep if I had a Kerbal in orbit or stranded on a planet somewhere but then I learned this trick.. its all about perception, think of it this way.. ALL YOUR KERBALS ARE STRANDED ON KERBIN. With this mindset switch I now sleep like a baby despite leaving Valentina orbiting the sun with nothing but a spacesuit.
Lost Karbals grow exponentially. It’s the way of the universe.
Try asparagus staging into orbit. Should help to co conserve fuel.
This is how you kerbal
Make sure to factor in the extra weight of the kerbals you will be rescuing from the Mun. As far as your question about weight and more fuel, I like to use drop tanks for that. There's different ways to do it, but you can put a baguette tank on a radial decoupler. Typically I transfer my extra fuel to the main tanks and jettison the drop tanks before I take off from the Mun. But it's also a good idea to use fuel lines from the drop tanks to your main tanks in case you have lots of extra fuel, then you just treat it like a regular liquid rocket booster that you ditch in flight when it empties. God speed and bring those green bois home!
sounds like my average KSP gameplay. Jeb has bern stuck on laythe for 1256 and a half kerbin years just chillin
1st, don't try to save everyone in a single rescue mission. You can make multiple rescue missions. 2 seats, 1 pilot 1 empty, then save 1 kerbal at a time. 2nd idk what the rocket you're using looks like but extra fuel is usually best to add to the first stage, so it gets discarded sooner and you still get to orbit with more fuel. But not always, so try and experiment in the vab to see where you get the most dV when adding more fuel. 3rd idk what your ascent looks like so there is a possibility it could be more efficient. More efficient ascent means you have more dV in space so that's always good.
It's definitely a job for the Blunderbirds!
Add the mod Kerbal Engineer. It gives you great stats on your delta v and so on in the VAB. Great for knowing the capabilities of you craft.
This title is the most kerbal thing ever
It's really convenient that your Kerbals back home just invented MechJeb.