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Can this land on the Mun and return?


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I think this IS definitely capable of landing on the Mun. Not that I've succeeded yet -- I've exploded one and crashlanded another. I don't think it has enough to get home, though as I was down to less than 700 D/V afterward. Needs more work. More powerful launch engine(s)?

The Girders work fine by the way -- they are intact though the parachute isn't.

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What would I need to boost the TWR on any/all stages? Just adding fuel seems to be a losing proposition.

Rocketry is like that.

Add more fuel to the boosters, and more powerful engines on the central stack. You want lots of thrust at lower altitudes, but less weight going up.

Is that a Poodle engine on the lander stage? If so, ditch it in favour of an LVT-45, which has a better TWR.

Also, take fuel off the lander. You do NOT need that much on it to land and take off from the Mun.

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Guest Brody_Peffley
Rocketry is like that.

Add more fuel to the boosters, and more powerful engines on the central stack. You want lots of thrust at lower altitudes, but less weight going up.

Is that a Poodle engine on the lander stage? If so, ditch it in favour of an LVT-45, which has a better TWR.

Also, take fuel off the lander. You do NOT need that much on it to land and take off from the Mun.

The fuel is good in the boosters. He needs more engines on them though. The TWR is very low. And I bet once its left off. Its going to be sliding off the launchpad and starting tipping over. This happens alot when your acceleration isn't very good.

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OK, I was under the impression that the vanilla Kerbal X could "make it to the Mun but getting back may be an issue." This has significantly MORE delta-V and it is still having trouble getting there and back.

OK, I'm still a significantly-under-average player at this point... :blush: but still.

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I don't really know the DV values, but I think you could make it back to Kerbin, if you waited until the ship on the Mun is facing retrograde (relative to Kerbin). This way you could save some DV by not having to circularize or even get into stable orbit around Mun. (Meaning that you could fly straight, backwards relative to Mun's orbit.) Quicksave before trying... :)

If you landed on either of the poles or near them, it may not work though.

Edited by jmiki8
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So you folks know, I have been able to (badly) land the Kerbal XL1 on the Mun:

http://i.imgur.com/iHJWAxi.png

But now I have 700 DV left, so even if I could stand the poor thing back up, I doubt it would make it home.

Welp! This looks like an opportunity to figure out how to land a rescue mission with a hitchhiker storage container! Or a lander with four outboard 1.25m engine stacks topped with Mk1 command pods.

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So you folks know, I have been able to (badly) land the Kerbal XL1 on the Mun:

But now I have 700 DV left, so even if I could stand the poor thing back up, I doubt it would make it home.

700 m/s is going to be a little tight I think...

You'd need 640 m/s to get back in orbit (14x14 km) and ~200 m/s to escape the Mun with a Kerbin periapsis inside Kerbin atmosphere.

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700 m/s is going to be a little tight I think...

You'd need 640 m/s to get back in orbit (14x14 km) and ~200 m/s to escape the Mun with a Kerbin periapsis inside Kerbin atmosphere.

At the very least, it could get him back into a Munar orbit so he could pull something else with extra crew capacity up by it and EVA them over to get the heck out of Dodge.

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In my experience I've needed at least 9500 DeltaV to do a Mun mission without giving Jeb an anxiety attack and sometimes up to 11000 depending on my landing site. That's launch, circularize, transfer, change inclination as needed and circularize, land, launch, circularize, inclination change, transfer, circularize, land at KSP. But that's just how I do them. I know for sure it can be done with a LOT less DeltaV.

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In my experience I've needed at least 9500 DeltaV to do a Mun mission without giving Jeb an anxiety attack and sometimes up to 11000 depending on my landing site. That's launch, circularize, transfer, change inclination as needed and circularize, land, launch, circularize, inclination change, transfer, circularize, land at KSP. But that's just how I do them. I know for sure it can be done with a LOT less DeltaV.

A simple Mun landing, where you just aim at some reasonable crater that happens to be close to your orbit, requires something like 7500 m/s: 4500 m/s to reach LKO, 1100 m/s to transfer to low Munar orbit, 1300 m/s for landing and returning to orbit, 300 m/s for the return, and 300 m/s margin of error. Maybe add 500 m/s, if your ascent profile or lifter stages are not that efficient, and another few hundred m/s, if you prefer to make the landing safe and slow. Inclination changes, trying to land at some specific place, and not using aerobraking increase the delta-v requirements further.

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I'm pointed sideways inside the crater (parallel to the rim), and all my attempts thus far to point the ship UP the crater wall have failed. I suppose I could try flying an unmanned version of the same ship (with a probe core underneath?) to a pinpoint landing to retrieve this stranded crew.

In other saves, I have landed this ship with MechJeb help, but ran out of fuel before return. I'm also in career mode and have an 8000 m/s ship that should be able to orbit the Mun or Minmus and has thus far succeeded in an unmanned flyby and return. Pics later. The experience (and help from you folks) with the Kerbal XL1 has definitely made a difference, so thanks!

Edited by JenBurdoo
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Well, the modifications are going well so far, but I am concerned about, as several people have mentioned, the lander tipping over. However, I haven't learned to set up fuel lines yet. Would it be possible to attach the landing legs to girders sticking out from the body of the craft? How likely would they be to break?

If you are already using girders, ditch the legs! Girders have *excellent* landing ability, if you dont mind the butt-ugly look. (use two girders, with a kink between them. allows flexing, thus allows landings up to 50m/s or so)

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It looks good enough to do a flyby. However, you want fuel left in the insertion stage to do most of the landing if you want to keep a nearly full fuel can in the lander for return.

A ring of boosters on the launch vehicle may be enough to give you that extra fuel needed.

Go for Minmus first. It is far easier to land in the sea there and will give you the landing experience needed for a more demanding one on Mun.

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I've got a few tips for your next lander.

Unless you really need 3 guys on the Mun switch to the Mk1 pod. It's about 3 tons lighter and you'll gain loads of dV.

If you want to move your landing legs out a bit, use the radial decouplers with the most offset. They're lighter than girders and you can fit stuff inside them. If you're really short on dV you can drop them once you lift off.

Finally if you keep tipping over you might want to try Minmus first. It takes about 100 extra dV to get there compared to the Mun, but you can get from orbit to the surface and back to orbit with less dV than it takes to get to the surface of the Mun. There's also gigantic areas that are totally flat to land on and your EVA pack will let you travel in about a 10 km radius of your lander to visit other biomes.

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  • 2 weeks later...

Thanks for all your comments and help, guys. I landed on a moon (Minmus) for the first time:

https://www.dropbox.com/s/73mmnfzmm61wrkn/Screenshot%202014-02-13%2000.52.44.png

Here's the ship I ended up building, complete with asparagus staging:

https://www.dropbox.com/s/66d9zrs9bcapxto/Screenshot%202014-02-13%2003.37.31.png

I even landed back at KSC (after some aerobraking practice), with well over 1200 science points:

https://www.dropbox.com/s/qtzlqa830rw3wpn/Screenshot%202014-02-13%2003.09.49.png

You guys gave me the confidence to make Touchdown II a success. I am so proud of myself and my Kerbals right now. Thank you!

Now to rescue the trapped Kerbal XL1 in the crater...

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  • 4 weeks later...

Well, my first dress rehearsal for a rescue attempt failed miserably. I did manage to target the center of the crater where Bob, Bill and Jeb are, but ran out of fuel on the way down. The crew was on a suborbital trajectory to the far side of the Mun; luckily I had quicksaved...

Edited by JenBurdoo
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  • 7 months later...

Certainly, you can land with some very big and expensive ships and return.

MP3bFwS.jpg

This three stage mod using SRBs landed six Kerbals on Minmus;

aTkAdzw.jpg

z3MsoXi.jpg

Ima3QAU.jpg

Or,

Build a simple design using the single pod and the mission will be a lot cheaper and easier.

h669f6P.jpg

Edited by SRV Ron
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