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How to Recover a Kerbin on escape trajectory


Emil Alexandru
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Hello, I'm new to KSP. I started career mode from start, I'd rather learn about all the components from small to large in slow motion rather than playing sandbox where there is too much info or possibilities.

So my situation is that I've lost a Kerbin, lost from orbit, in an escape trajectory with a speed of 1754 m/s orbit and 3488 m/s surface at an altitude of near 10 milion meters, i have no more electric charge on the pod, nothing but the pod and the Rockomax Brand Adapter attached to the pod.

So my problem is that I cannot find a way to build a rocket that can escape orbit, match and exceed the velocity of the lost Kerbin and set a meeting trajectory.

I am asking for suggestions on how to build a rocket that will help me recover the lost Kerbin. I have tried with 2x Mk1 pod, 1 with pilot and the other empty, but I cannot escape again with enough fuel left to set a meeting trajectory, recover, then burn back to Kerbin to reach an orbit or land.

Here you have the screenshots with the situation and also with my R&D so you know what can I build and what not.

Now I only have 1 pilot remaining that I can use, the other is on escape trajectory and another is dead due to crash (didn't know that if you are in orbit, switch to tracking station, get back to the ship in orbit, crash, you cannot reset to "launch pad" or "VAB")

This is my 3rd time I've lost pilots, got without a pilot, and had to reset career in order to keep going. Not enough pilots waiting to get hired.

I have tried getting out of the pod with the pilot on EVA but the moment I do the pod gets a rotation because of switch in the center of gravity and it is complicated to make it stop rotating, point it to the planet and then start push forward without causing another rotation to the pod. 1/2 of EVA fuel is lost just trying to keep the pod pointing forward to the planet, the other half is used for pushing.

Thank you in advance for all your suggestions.

 

R&D Screenshot : https://s10.postimg.org/ak4773xrt/screenshot2.png
Lost Kerbin in space situation :

1- https://s10.postimg.org/4j6ia2dqh/screenshot0.png

2- https://s10.postimg.org/et8x9bqrd/screenshot1.png

3- https://s10.postimg.org/46f43waw9/screenshot3.png

4- https://s10.postimg.org/szoo4jm6x/screenshot4.png

Or the entire gallery : https://postimg.org/gallery/11k7n4g1y/

Edited by Emil Alexandru
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2 hours ago, Emil Alexandru said:

Would it do if I get with the pilot out of the pod and using the EVA thrusters towards the planet to at least stop the pilot from an exit trajectory?

Not gonna work you will run out of EVA fuel before reaching a closed trajectory.

you could try to go to EVA and 'push' the command pod and before you run out of EVA fuel re-board and EVA again (with a replenished tank) and repeat. But that would be tedious and difficult.

 

2 hours ago, Emil Alexandru said:

How much will Kerbin last in pace without its pod ?

well, if you zoom out in map mode you can see Jeb's orbit around the Sun. It's unlikely he will hit anything (space is mostly empty) and since there is no Life Support in the stock game he can stay indefinitely in orbit. And rescuing him later will be probably easier with things like solar panels and  more advanced probe cores, also with more player experience too.

 

Meanwhile a good idea is to try to figure out what you did wrong to end up in this and other bad situations, to avoid doing it again in the future. How about talking about  the rocket you launched, your goal  and how you were handling it?

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Instead of career mode, you'd be better off getting a feel for the game in science mode.  Sandbox just overwhelms you with parts, career means you have to worry about funds and such.

Anyway, if you can at least unlock the OKTO and a good antenna, you can do rescue missions for OTHER Kerbals.  You can also do missions with just the engineer or scientist.  The OKTO is far better than the Stayputnik because it provides SAS functionality.

Rescuing that Kerbal might be a bit tricky, depending what parts you have unlocked, and time is something of an issue.  It really depends what you have available, and the size of your launchpad.  To even catch the thing, you're going to want about 7000 m/s delta-v off the pad (vis-visa to the rescue, height and speed were enough), add maybe 1000-1500 so you can catch up in solar orbit and adjust your orbit to recover afterwards, but it's not going to be fast.

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14 minutes ago, Kryxal said:

Instead of career mode, you'd be better off getting a feel for the game in science mode.  Sandbox just overwhelms you with parts, career means you have to worry about funds and such.

Anyway, if you can at least unlock the OKTO and a good antenna, you can do rescue missions for OTHER Kerbals.  You can also do missions with just the engineer or scientist.  The OKTO is far better than the Stayputnik because it provides SAS functionality.

Rescuing that Kerbal might be a bit tricky, depending what parts you have unlocked, and time is something of an issue.  It really depends what you have available, and the size of your launchpad.  To even catch the thing, you're going to want about 7000 m/s delta-v off the pad (vis-visa to the rescue, height and speed were enough), add maybe 1000-1500 so you can catch up in solar orbit and adjust your orbit to recover afterwards, but it's not going to be fast.

Thank you for your answer, I have installed the Kerbal Engineer Mod so i can see the delta-v while building.
You can see from the first screenshot what i have researched and what i can build, i currently don't have access to OKTO, only Stayputnik.

My VAB Level is 2, my Tracking Station level is 2, my Launchpad Level is 2, my Mission Control level is 2, and my Astronaut Complex Level is 2, the rest are at level 1.
 

Just one thought. Would it do if I get with the pilot out of the pod and using the EVA thrusters towards the planet to at least stop the pilot from an exit trajectory? Abandon pod! Then try to rescue him while he is not moving further away.
Is the thrust from the EVA enough to counteract the 1745 m/s speed he is moving away?

Because right now I've stopped all my activities not to allow the pod to move further, I cannot do anything but stay on pause.
How much will Kerbin last in pace without its pod ?

Thanks!

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25 minutes ago, Spricigo said:

well, if you zoom out in map mode you can see Jeb's orbit around the Sun. It's unlikely he will hit anything (space is mostly empty) and since there is no Life Support in the stock game he can stay indefinitely in orbit. And rescuing him later will be probably easier with things like solar panels and  more advanced probe cores, also with more player experience too.

I will do this, i will try to focus on other missions in order to get science points and get better crafts for recover later

25 minutes ago, Spricigo said:

 

Meanwhile a good idea is to try to figure out what you did wrong to end up in this and other bad situations, to avoid doing it again in the future. How about talking about  the rocket you launched, your goal  and how you were handling it?

I had a mission where I had to Haul a decoupler into an escape trajectory. It is very difficult to fly without SAS so I put my best pilot on board, flew to escape trajectory and haul that decoupler, I did this thinking I can hit escape and return to VAB to modify the rocket in order to get the pilot home. So it was a test mission knowing i can revert it. But! While in space, on an escape trajectory I hit Space Center and then Tracking Center. In that moment I lost my ability to click Revert to VAB.

The second pilot i lost was due to trying to rescue the first one, but as I am a beginner it is trial and error, so I didn't manage to make an orbit to intersect and with the fuel i had left I lowered my periapsis to land, but due to not appreciating the heights of the mountains I lost the second one too the same way I list the first. I lost the ability to press REVERT.

Now I have installed a mod that makes multiple quicksaves and does not overwrite.


About intersecting. I went up at about 200km and then set target to the lost pilot and burned towards the red target in the navball which is this one 90px-Target_prograde.svg.png (Hope i did right), still not able to intersect due to bad rocket designs or not enough R&D. I can only orbit or escape apparently :D 

About the Maneuver, will the target appear on maneuver if I intersect orbits?

 

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Mind you, if you remember to do it yourself you don't need a mod.

ALT+F5 creates a named quicksave (same if you open the menu and select save)

ALF+F9 to select a save to load. (or load from the menu)

 

BTW you can change your setting  to dead kerbals respawn...it will not help with the ones that are already KIA but if the next mishap will make then only MIA and s/he will show up again after a while.

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58 minutes ago, Emil Alexandru said:

I had a mission where I had to Haul a decoupler into an escape trajectory. It is very difficult to fly without SAS so I put my best pilot on board,

Escape trajectories are very easy to reach, even without SAS.  Build a big rocket with fins, launch straight up, go real fast, hit escape velocity.  It won't be perfect, but it should work.  There's no need to create a stable orbit here. 

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16 minutes ago, Spricigo said:

Mind you, if you remember to do it yourself you don't need a mod.

ALT+F5 creates a named quicksave (same if you open the menu and select save)

ALF+F9 to select a save to load. (or load from the menu)

 

BTW you can change your setting  to dead kerbals respawn...it will not help with the ones that are already KIA but if the next mishap will make then only MIA and s/he will show up again after a while.

The "dead" pilot i had was Missing in action and deleted it. Eh maybe more pilots will come to get hired. Now i'm teaching this one prograde and retrograde

 

7 minutes ago, Gargamel said:

Escape trajectories are very easy to reach, even without SAS.  Build a big rocket with fins, launch straight up, go real fast, hit escape velocity.  It won't be perfect, but it should work.  There's no need to create a stable orbit here. 

Well i did that but it was just for test thinking i can hit revert to vab but that dissapeared the moment i went to tracking center. I did not back a return rocket.

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15 hours ago, Emil Alexandru said:

The "dead" pilot i had was Missing in action and deleted it. Eh maybe more pilots will come to get hired. Now i'm teaching this one prograde and retrograde

 

Well i did that but it was just for test thinking i can hit revert to vab but that dissapeared the moment i went to tracking center. I did not back a return rocket.

 

Just one last question and mods can close this thread.
Somewhere in the future the planet and Jeb's orbit will intersect, I don't know if they will actually meet but it seems like an opportunity to recover Jeb.
Could anyone give me some advice on how to do that?

screenshot6.png
screenshot7.png
screenshot8.png


Also it appears that Jeb is moving slight faster than Kerbin

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He is moving faster, but will end up going outside Kerbin's orbit and losing ground later.  The best way to check for close approaches is to set Jeb's craft active and target Kerbin.  Anyway, I'd aim to launch a craft at the orbit intersection at about the 7 o'clock position on a similar but faster orbit so as to intercept in one orbit from that point, then do a few more orbits and recover ... and get that OKTO (and a higher-end antenna) in the meantime, being able to work unmanned is great for a rescue mission!

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@Emil Alexandru:

First, welcome to the forum.  The good news is that you came to the right place to get help.

The bad news is that at this point in the career, it would be very difficult to provide that help.

I'm not saying that Jeb cannot be rescued--quite the opposite, in fact.  The problem is that you don't have the means to rescue him right now.  Part of that is that you don't have access to the high-level parts, part of it is that you lack Funds, and part of it is simple timing, which is to say that because he's on an escape path directly away from Kerbin right now, you're better off waiting until he's moving in a more convenient direction relative to the planet.

Another part of it is technique--by this I mean to say that, for example, when you chased down his ship by going in the :targetpro: direction, even if you had caught him, it still would have left you with a ship that was escaping.  You'd still need to burn just as hard to stop and come back.  Since you got into this mess because your ship could go out but not come back, it's just the same problem over again, only with an additional lost pilot and wasted money.

You mentioned that you can orbit and escape:  that's good!  To efficiently rescue Jeb, you're also going to need to know about transfers, rendezvous, and intercepts.  You can learn about transfers by going to the Mun and Minmus.  You can do rendezvous in orbit of Kerbin (or either of the moons).  Intercepts (which I here define as combining transfers with rendezvous) will require you to work out trips from the Mun to Minmus, or vice versa.  You can also do this with interplanetary journeys, but advanced transfer windows between the moons occur about every twelve to fifteen days and mistakes still leave you in Kerbin orbit, so you'll have more opportunity to practise them and less cost for failure.

Once you have all of that, then you ought to be able to set up a mission to rescue Jeb.  In the meantime, your missions to the Mun and Minmus can get you more science and Funds, which will allow you to buy the better parts and make a rocket that's capable of performing the rescue without being unwieldy.

If it makes you feel any better, I timewarped my very first mission to the Mun and not only missed the capture burn, but got a gravity assist right out of Kerbin planetary space before I could slow time again.  Jeb spent six years working on his tan in solar orbit before I had both a craft capable of rescuing him and the skills to complete the mission, but he did get home.  You can do it, too.

Edited by Zhetaan
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3 hours ago, Zhetaan said:

@Emil Alexandru:

First, welcome to the forum.  The good news is that you came to the right place to get help.

 

Hello and thank you for the long answer. It is always a pleasure to see that someone answers with interest in the subject.
Thank you also for your advice.

Yesterday I managed to go to the moon. Actually I was doing an escape mission to haul something but then I said, hmm lets play with maneuver more, so I did the escape then projected some burns to go to the moon. I managed to land but I was not prepared with landing legs so my rocket rolled horizontally a little, then I went out planted a flag, did an EVA report and back to the pod. The problem was that I was horizontal so no way to launch, also fuel was problematic so I maxed out thrust to explode and reset.
Right now after replaying to your message I am going to do the same mission only with Landing legs and some more fuel, I'll try a different design of the ship to loose the weight and save some fuel.


I am going to save Jeb who is right now orbiting the Sun, but I will do this in the future, right now I cannot venture to far.

 

Just one question about Maneuver. I see normal-antinormal, radial in-radial out, prograde-retrograde. I am curious if I will be able to see on a Maneuver node "Target" that adjusts the orbit on all angles at the same time?

Edited by Emil Alexandru
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26 minutes ago, Emil Alexandru said:

Just one question about Maneuver. I see normal-antinormal, radial in-radial out, prograde-retrograde. I am curious if I will be able to see on a Maneuver node "Target" that adjusts the orbit on all angles at the same time?

Available for pilots and probecores lvl3 and higher.

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6 minutes ago, Spricigo said:

Available for pilots and probecores lvl3 and higher.

Thank you for the answer. Would you be kind enough to give me another one.

In a Rocket how should the Center of Mass, Center of Thrust and Aerodynamic Overlay should be relative to each other and to the rocket (top, middle, bottom)?

Thank you!!!!

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So my first try was a bust. :D

screenshot49.png


screenshot50.png

 

Not enough fuel to get back.

Also it is a nightmare to stay vertical on the moon without SAS. Turning over SAS made my rocket to turn horizontal.

So I gave it another try. I packed 4 boosters to give me an extra lift so I can have enough fuel.

 

Now I'm close to land with 2 tanks full. :D

screenshot73.png


screenshot74.png

 

I also did a lot of science until this point. I will do more on the moon + I have a Science Jr with me :D hehe

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Some things to make your life easier:

For a lander, short and squat is a VERY good idea, even if it makes for problems leaving Kerbin.

It's best to aim for an orbit to start with, don't aim to plow into the planet.

Aligning retrograde makes landing pretty easy if you know when to burn.

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4 hours ago, Emil Alexandru said:

Just one question about Maneuver. I see normal-antinormal, radial in-radial out, prograde-retrograde. I am curious if I will be able to see on a Maneuver node "Target" that adjusts the orbit on all angles at the same time?

High-level pilots and probe cores can point directly towards :targetpro: (or away from :targetretro:) the target using SAS, but if you're asking whether the node creator in map mode will give you a handle that lets you easily plan an intercept, then no; that is something you'll have to do on your own.  As you will discover, when dealing with orbital mechanics, pointing towards the target and burning the engine doesn't work unless you have already completed a rendezvous.  The SAS target marker only points the direction; it's doesn't account for the fact that everything is moving, so the only time it also points in the direction to burn is when you and the target are already moving in exactly the same direction at exactly the same speed.

4 hours ago, Emil Alexandru said:

In a Rocket how should the Center of Mass, Center of Thrust and Aerodynamic Overlay should be relative to each other and to the rocket (top, middle, bottom)?

The aerodynamic indicator is mainly for fixed-wing craft (meaning aero- and spaceplanes).  For most rockets, it doesn't mean much.

The centre of mass ought to be fairly towards the top of the rocket, though when it is fully loaded with fuel, it is acceptable for the centre of mass to be a bit closer to the middle.

The centre of thrust should be where the engines are.  This marker also has an arrow pointing out the bottom of it that shows the average direction of the rocket exhaust.  What that means is that the rocket should move in the exact opposite direction--and if you draw an arrow exactly opposite the thrust arrow, it should go directly through the centre of mass.  Achieving this is easy if you keep your rockets symmetrical.

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Thank you for all the info.

Until now I have landed on the moon several times with quicksaves. Problems, not being able to stay vertical, tried different approach, direct plow, orbit then try to land where my speed is lowest, problem with not enough fuel to get back to Kerbin.
Now I selected a save from before launching for the moon, trying to adjust the orbit of encounter from behind the moon, like trying to catch it, not coming from her front, also for fuel efficiency.

EDIT : Too bad the maneuver mode only tells you the speed needed for the first maneuver, it doesn't show for the second or third, like a total speed required.

Edited by Emil Alexandru
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On 27/02/2018 at 5:37 PM, Emil Alexandru said:

Just one thought. Would it do if I get with the pilot out of the pod and using the EVA thrusters towards the planet to at least stop the pilot from an exit trajectory?

Yeah I'd say if you don't want to leave your kerbal in space for ages. Make a quicksave ,Jump out the pod and burn retrograde .

As long as you have enough Eva fuel to get back into a stable orbit then personally I'd say It will be easier to rescue them. especially if you haven't went interplanetary  yet/learned to rendezous on an interplanetary scale (kind of). 

Plus if your early career  you may miss a transfer window to Duna / Eve while spending the time to rescue the kerbal on a solar orbit. 

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Yes, you can forget about getting Jeb back now.

It will be several years before Jeb's orbit puts him and Kerbin anywhere near the same place at the same time.

It's also highly likely that the two orbits are not any kind of resonant relationship (e.g. where 3 orbits by Jeb would take exactly the same time as 4 or 5 orbits by Kerbin), so if you leave things as they are they may not actually meet again for hundreds of years.
That's not something to worry about now, either, since the first time you can actually do something reasonable about it will be when Jeb is at solar AP, which is more than half a year away. By that time you should have much more capable rockets and much better intercept skills, so you might as well just leave him.

One thing to bear in mind though: there are few things harder than trying to get an astronaut with zero EVA fuel onto a ship. So if you do ever consider using EVA to make a rendezvous, plan to use significantly less than the 600 m/s or so dv that you can get on a full jetpack. You always lose some fuel just by moving the camera around and trying to aim in the right direction. So it is definitely far safer and easier for Jeb to stay in his dead craft and get grabbed later; grabbers can't grapple astronauts like you see in Kubrick's 2001.

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23 hours ago, Plusck said:

 So it is definitely far safer and easier for Jeb to stay in his dead craft and get grabbed later; grabbers can't grapple astronauts like you see in Kubrick's 2001.

Too late by now, he is already in space. Tried to stop his escaping trajectory using his EVA jetpack.

screenshot139.png

I will rescue him in the future.

 

By the way regarding to my moon trying to land and get back to Kerbin. I managed to do it.

But because I didn't have enough fuel to get back easier I had to make an aerobreak maneuver that put me in orbit of Kerbin at periapsis at about 40.000 and it took about 3 orbits to slow down enough :D but it was AMAZING, passing through low orbit first at 3000 m/s speed for 3 times before landind

screenshot117.png

 

 

 

And I also managed to land with 302 Science :D

 

screenshot133.png

 

Edited by Emil Alexandru
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On 2/27/2018 at 3:47 PM, Spricigo said:

Meanwhile a good idea is to try to figure out what you did wrong to end up in this and other bad situations, to avoid doing it again in the future. How about talking about  the rocket you launched, your goal  and how you were handling it?

I currently have two Kerbals on escape trajectories. They got there because I was completing an escape trajectory mission, but I don't think I have the technology yet to come back from one. I suppose I'll have to wait until I advance and try to rescue them then.

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@Nox Astrum That is a quite old question (in fact, ancient), for a problem you currently have is preferable to post a new question. 

 

Anyway. If you have [Missing crew Respawn] checked on difficult options and don't consider it 'cheating' I think you can go to your tracking station select the craft your kerbals are in and terminate it. The crewyou go "missing" and respawn after a while (depending on difficult option)

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