In need of a rescue mission on the Mun, how to?

[bigred]

Jebadaiah Landed on the Mun, great success. However, My lander doesn't have enough fuel to get back to Kerbin, How would I go about rescuing him off the surface of the Mun? I don't want to lose my most experienced astronaut.

Could someone draw up a rescue mission with a rocket/ship fit?

Thanks!

N.B. > I am doing a stock career, no mods.

[Alshain]

Does it have enough to get to munar orbit? That will be easier than landing a rescue mission.

Also, welcome to the forums! In the future there is a questions forum this would be more appropriate for.

[Belphegor]

try it the same way as you did before, but get some more fuel on your lander and compensate on your lower stages for the added weight.

my first moon mission ended like this as well and the 2 rescue missions with similar stick-like landers too. i made a completely new lander, a science lab module (to store all the data the 3 stranded kerbals collected) with a small pod on top, and 4 t-400 (or something like that) fuel tanks attached to the side for stability, each with the (R-90something?) engine underneath (the small economical ones). and some thrusters for landing.. used it for everything from getting orbit around the moon after the transfer to the landing at kerbin using only 3/4 of it's fuel and it got 2 kerbals back

good luck

edit: you could also leave him there you know.. makes 'plant flag on mun' contracts very easy. that's why i left a guy behind

Edited August 19, 2014 by Belphegor

[Vanamonde]

This question about how to play the game has been moved to Gameplay Questions.

[Malaugrym]

There are only two requirements for rescue missions: Enough delta-v to make the trip and enough space for all relevant kerbals.

In all honesty, figuring out the ship design for yourself would be the most rewarding course. That is kinda the point of the game.

[magnemoe]

reaching orbit simplify stuff, if not and you can not land 5 km from him its best to land a rover drive it to him and then launch to orbit.

Hint: use a 45-90 liter tank, probe seat, don't forget solar panels and batteries. radial decoplers, grinders and wheels on the ends, smarter to add the two and two.

now you have a rover who can land on Mun and you drop he wheels on takeoff, this is not much more expensive than just landing a rover.

[TheDarkStar]

reaching orbit simplify stuff, if not and you can not land 5 km from him its best to land a rover drive it to him and then launch to orbit.

Hint: use a 45-90 liter tank, probe seat, don't forget solar panels and batteries. radial decoplers, grinders and wheels on the ends, smarter to add the two and two.

now you have a rover who can land on Mun and you drop he wheels on takeoff, this is not much more expensive than just landing a rover.

Or you can use a normal lander to land nearby and then use the Kerbal's RCS pack to get him over if you can slow him down for impact.

[sedativechunk]

... you people recommending him go to orbit, I disagree. OP, have you done an orbital rendezvous before with anything? If not, then do not even thing about attempting to put Jeb in orbit! There are a billion things that could go wrong. The biggest one being that your lunar intercept will put you in an orbit in the opposite direction that Jeb is going in. You would have burn alot of fuel to correct the orbit and then burn even more to catch up with Jeb. I think a plain and simple rescue mission, try to land right on top of where he is, it may take some practice to get close to him. Your orbit, you will have to put the orbit "past" where he is on the Mun, because as you burn retrograde that path/orbit will move in.

TO build a rescue rocket, I'm assuming you got the MK1-2 pod to house three Kerbals, build something with that. If not, you can always add a ladder or something for Jeb to hang onto. Make a rocket using the tiny rockomax engines:

http://wiki.kerbalspaceprogram.com/wiki/Rockomax_48-7S

These are extremely small/light weight/fuel efficient for landing on the Mun. Make a simple fuel efficient lander and land close to Jeb. I could probably do it easily but it's hard to explain!

[Zylark]

Your basic "To the Mun and back" rocket.

Made with all stock parts - no extras included.

The Lander and return vehicle:

Top to bottom:

Parachute - you'll need this later.

Capsule - one kerbal only. If rescuing anyone, send off unmanned.

2xInline Parachutes - you'll need this later

---

Decoupler

Fuel tank - can never remember what they are called, but holds enough fuel for the return trip and then some.

2xBatteries - power you will need, but not much.

4xSingle cell solar panels - for recharging batteries, probably not needed but just to be safe.

2xRadial decouplers - also doubles as girders to widen your craft a bit.

2xTiny Fuel tanks - for Mun deorbit and landing.

4xLanding legs - for, well, landing.

2xLV909 - for Mun deorbit and landing.

LV909 - for taking off from mun and return to Kerbin.

Now all one need is something to carry this thing up to Kerbin orbit, say 100km, and get it towards Mun. This booster will do nicely:

Again, top to bottom:

The lander and return capsule from above.

Decoupler

Advanced Stabilizer - probably not needed, but makes everything much easier to control.

Fuel tank - the long one that holds 360 units of fuel.

4xSingle cell solar panels - probably not needed, but again...

2xBatteries - electricity is good.

LV-T45 Engine - plenty powerful enough for our needs.

Decoupler

Tri-coupler

6xFuel tanks - the long ones stacked two tall.

3xRadial decouplers - for hooking up those Solid Rocket Boosters

3xSRBs - again, the long ones, not those tiny short ones.

6xSepatrons - 2 per SRB. Without these you'll have a sudden disassembly when separating the SRB stage

3xLV-T45

3xLaunch Stability Towers - strictly speaking not needed, but I like them.

Staging (parachutes and stuff to recoup launch costs removed for clarity):

6: Fires all booster engines (3xLV-T45 + SRBs) and release the rocket from the towers.

5: Release the SRBs and fires the Sepatrons.

4: Release the lower booster stage of 3xLV-T45 + Fuel tanks. Fires upper booster stage.

3: Release upper booster stage. Fires 3xLV909.

2: Release 2xLV909 + Fuel Tanks

1: Release LV909 + Fuel Tank

0: Deploys capsule Parachutes.

Schedule:

1: Stage 6, 5 and 4 will get you to Kerbin orbit, with fuel left over in the upper booster to get you well on your way to Mun

2: When stage 4 is dry (upper booster), release it and finish whatever maneuver you were doing. When done, transfer fuel from middle tank to top off the radial tanks.

3: Orbit and then land on Mun. If any fuel is left over in the radial tanks, transfer it to the middle tank.

4: Do your Mun business.

5: Take off from Mun. Once the landing legs are off the ground - release the radial tanks and engines.

6: Once in Mun orbit, plot a course directly for Kerbin. Aim for a Pe of 0 to 10000 meters.

7: Before hitting the atmosphere of Kerbin, point capsule prograde, release LV909+Fuel tank.

8: When in atmosphere, point capsule retrograde (doesn't matter but looks better).

9: After the worst of the re-entry fires, release parachutes.

10: Happy landing.

---

That lander and booster setup can be embellished on to do some science as well, by simply strapping a Science Jr pod under the capsule and then bolting on various science instruments and such to the Science Jr pod. Though, to be certain of a happy return, Id also add an inline Parachute or two to the Science Jr Pod.

Good luck and have fun

Edited August 21, 2014 by Zylark

[Kerolyov]

The difficulty with rescue missions is that you have to make sure you have plenty of fuel and know how to land close to first ship or if its in orbit to rendevous and dock. You also need an extra lander can or cockpit that is unmanned for your rescued Kerbal to get into.

To make the moon rescue easier you want plenty of delta-V (if you haven't learned this concept then its worth doing as you'll get so much more from our designs), you can get advice here:-

http://en.wikipedia.org/wiki/Delta-v

forum.kerbalspaceprogram.com/threads/47929-How-to-use-Tsiolkovsky-s-rocket-equation-to-find-out-my-total-delta-v

In a nutshell delta-V is how much your rockets speed is changed by burning the rocket fuel. The more delta-V you have the more you can do. More delta-V either needs more fuel or more efficient engine.

From this delta-V map you can see get to the moon you'll need:-

~4500 delta-V to get into Kerbin orbit

~900 delta-V to get to the Mun

~300 delta-V to get into orbit around Mun

~600 delta-V to land

another ~600 to take off

~300 to get get orbit to intercept with Kerbin

You don't need to go into orbit at Kerbin so you can save the ~900 delta_v and just re-enter and land by parachute

The maps show ideal "perfect pilot" values and particularly for landing you'll need 10-50% more than the chart says. So you might need nearly 1000 dV to land on Mun and 700 to takeoff, unless you really know how to land efficiently. I'd take plenty extra for a rescue mission too.

~4500 Kerbin Orbit

~900 to Mun

~3000 to Orbit Mun, land, rescue and takeoff

As you get more experienced at design and piloting then you'll be able to save more fuel/delta-V

I'd also recommend taking a look at this guide

http://flyonbudget.onegiantleap.info/chapter1.html

Hope that helps you. My intention is to get you thinking about how to design a mission yourself, you'll get a lot more from the game that way!

Happy flighting

PS If you do use mods in future, take a look at Kerbal Engineer it calculates delta-V for you as you build the ship

Edited August 20, 2014 by Kerolyov

[bigred]

This is great, really great. Thank you Zylark and the rest. I'll give it a go soon. This game is just awesome fun. I really like your setup, my main problem is just that, getting something in the air and in orbit efficiently with enough fuel. Fuel overall is my biggest challenge in KSP, as in never having enough.

Thanks again, My next challenge later on will be rescuing a science probe that didn't quite make it and is stranding in a large elliptical orbit around Kerbin, I'll wait until I get the Grabber unit and a few other tech improvements before attempting that though.

[Zylark]

my main problem is just that, getting something in the air and in orbit efficiently with enough fuel. Fuel overall is my biggest challenge in KSP, as in never having enough.

Fuel needs are difficult to guesstimate. Why I'd strongly recommend a mod such as Kerbal Engineer Redux or Mechjeb. Both will give you vital information on your rockets dV and thrust to weight throughout the stages and even adjusted for other planets and moons as you are building it.

As for getting to LKO (Low Kerbin Orbit) it is done in a few easy steps - assuming you got a stable rocket that do not behave like a wet noodle:

- Press T to activate SAS then throttle up to max.

- Start your rocket, go straight up for the time being.

- At 10km up, rotate right until your rocket tilts 45 degrees.

- At 20km up, rotate to follow the prograde marker on the navball, add say 5 degrees lag to it.

- Shift to map view, bring up the navball, keep an eye on the AP readout by hovering the mouse over it. Continue to follow the prograde marker.

- When the AP readout says 100km (or whatever is your desired orbit altitude) cut engines and coast until you are at AP.

- At AP, point about 5 degrees below the prograde marker, fire up the engines again until the PE marker is at same altitude as the AP marker.

That should give you a nice circular orbit in a pretty fuel efficient manner.