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Small Mun lander that can land and relaunch to dock in Mun orbit


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22 hours ago, Snark said:

Love the itty-bitty lander, but... how does that even fly?  I don't see any reaction torque ability anywhere. The OKTO2 doesn't have 'em.  Or am I missing something?  How do you steer the thing?

Yeah, gimbal does it but in practice that's an in-between design I chucked together for the the screenpic.  Lighter you can remove the docking port, one of the solar panels and one of the engines, replace the other engine with an ant.  Heavier I'd usually use a space-scooter like this (and I do, because it's fun) as illustrated and explained in http://forum.kerbalspaceprogram.com/index.php?/topic/72093-exploring-the-system-a-design-tutorial-campaign-090-final/&do=findComment&comment=1185911.  At 0,7t that gives a SSTO lander that "Can land on and re-orbit from any body except Tylo, Laythe and Eve. Landing OR re-orbit is possible on Tylo, but not both. You can even take this to Mun [from LKO] on its own if you really want to."

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18 hours ago, GoSlash27 said:

keyscapeunit,

 That's not a dumb question at all. You can't mathematically design a stage without a DV requirement, so knowing how much DV is needed is critical.

 If you just want a good reference, it's here:

600px-KerbinDeltaVMap.png

If you want to know the math behind it, I can explain that as well.

Since the DV from the munar surface to orbit is 580 m/sec, I multiply that by 3 for a round trip (landing in a precise spot is very wasteful of fuel). 1,740 m/sec DV is a comfortable amount for a round trip. 1,160 would be the theoretical minimum, but you won't manage to do it that perfectly. The more practice you have doing Mun landings, the closer you can shave it.

Best,

-Slashy

Thanks!  This is awesome.

4 hours ago, Scarecrow said:

Realising that a 3-man capsule may be more than is required for your particular needs, this smaller 1-man version is quite capable of visiting the surface from a 15,000m orbit and returning with fuel to spare.

smallmun.jpg

Where do you put your science equipment on that?

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While not the smallest you can make I feel this is a fairly clear and versatile craft (pre 1.0 I used this lander for a Duna mission).  It can be modified to use either the pair of radial mounted engines or a single engine underneath, I prefer the radial engines in case one of the legs breaks during landing.  I actually just took this picture after landing it as a test and the inner ring of tanks is still half full and the mid tank is full, again a modifiable design to either keep the tanks on to refill and land again or drop them giving you a single use lander.  You could add some science to this if it were to be used in career mode, however I believe a science jr would be a bit much for it to handle (maybe not). BlNxRTU.jpg

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18 hours ago, Scarecrow said:

Realising that a 3-man capsule may be more than is required for your particular needs, this smaller 1-man version is quite capable of visiting the surface from a 15,000m orbit and returning with fuel to spare.

smallmun.jpg

Nice and compact! :)

A few suggestions:

  • Consider losing the fuel ducts.  It'll be a bit less convenient (since you need to do fuel pumping)... but each one of those is adding 50 kilograms of mass, and you have four of them.  0.2 tons may not sound like a lot, but it's a significant fraction of the mass of a ship as tiny as that.
  • Do you really need those monopropellant tanks on the side?  The lander can itself holds 10 units of monopropellant, which ought to be plenty for docking a little ship like that.  Again, the mass savings is pretty big for such a small ship.
  • Suggest adjusting the RCS placement.  Where possible, it's always best for RCS thrusters to be at the cardinal up-down-left-right angles relative to the control-from point.  You've got them rotated at a 45 degree angle.  This will make them run inefficiently, they'll end up wasting 41.4% of their fuel.  Your current design leaves the left and right sides of the lander can completely free, so that would be a convenient spot.  Therefore, instead of putting four of the 4-way thrusters at 45 degree angles, as you've shown, you can just put two of the four-way thrusters (one each on left and right sides), with a 1-way thruster immediately below each one.  That will still give you full RCS steering control, and will make much more efficient use of your monopropellant when docking.  Plus it saves a smidgeon of mass, too (the one-way thrusters are 20 kg lighter, for a total of 40 kg of mass savings).
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  • 10 months later...

QDHKxum.png

 

This is Destiny 4 (4th design phase in the destiny landers). It's the perfect science pack for both the Mun and Minmus, for having every science experiment (exept for the atmosphere spectrometer fluid thingy, because of course, there is no atmosphere on the Mun/Minmus). It also has just enough ∆V for a landing from a 15-20km orbit and back on the Mun and Minmus, so that it can dock with an orbital craft, transfer science, refuel and other things, and land again to another biome for more science!

It has a very strange design in my opinion, for the solar panels and batteries were made with mirror symmetry.

Plo71WX.png

Just to let you people know, I do have a MechJeb unit on the craft, but ONLY for ∆V readings, and nothing else, for I don't trust MechJeb for things like landing guidance, autopilots and other things. Hope you think it looks good.

Edited by RedBee92
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My usual Mun science reaping system consists of three components.

A science station in orbit at just over 50km altitude.

A lander consisting of a Mk1 Lander can, a Materials bay underneath and two FL-T 200 fuel tanks one on each side. The tanks each have a 'Sparck' engine underneath and a couple of Micro legs. You can fill out the science stuff, battery and a solar panel mostly on top of the fuel tanks. Crucially the vehicle has two docking ports, one on the top of the cabin and the other under the materials bay. A variant of the RedBee92 design would also work fine if it had a port on the under side.

The third component is a tug consisting of a probe core, docking port, FL-T800 fuel tank, RCS, nuclear engine, lights, battery and solar panels. This docks to the port underneath the lander and carries it to targets under inclined orbits and down to lower orbits for landing. Being nuke powered it has bags of dV.

This way the lander only ever needs to drop down 8 to 10 km to the surface and the same back up to rendezvous with the tug. It also can be carried to reach targets at pretty much any location on the Mun. The science station is fitted out with fuel tankage to refuel the lander and a tank with just fuel (no oxidizer) for the nuke tug.

A few times I've blown the fuel budget on the lander and not quite made it to orbit, and needed to quickly fly the tug to dock with the lander and push it up into orbit before it hit the deck. Fun!

Simon Hibbs

 

Edited by simonh
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I'd say the main thing is that if you're planning to make repeated trips between the munar surface and a station in munar orbit,  leave most of your fuel with the station and only bring enough fuel for that one trip to the surface on the lander.   You dont want to be lifting tons and tons of fuel from the surface to orbit and back again.

For minmus i prefer a rocket car / spaceplane.

20160724134117_1_zpsqvcswioj.jpg

you can circumnavigate minmus for less delta v than a single landing. You only use fuel when climbing hills, on the flat and going down there is basically no friction.   Minmus is also tiny so this feat is not as unbearably slow as it would be on other bodies.  

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This is one of my go to landers.  I skip the ladder and just use the jet pack for getting in and out.  it has more Delta V then needed, but that helps for adjusting your landing zone, making life easier when your aiming for specific biomes.  the landing legs are also a step up from the smallest, giving you more forgiveness on landings.  I opt for the shielded solar panels so that i can have the option to retract them.  Also no gravioli on this one, simply because when i was planning this mission, i had limited tech nodes.  the 4 sparks give you a higher TWR then needed, but i like it like that.

Screenshot_2016_11_14_12_45_51.png

recently i used this monstrosity as the orbital vehicle. It had enough delta V to get me to the Mun, then to Minmus, and then a short swing by Duna and Ike. It carried enough fuel for 26+ individual landings. 17 for Mun, 9 for Minmus. I had enough for a couple more landings when i was done the 26.   although i do feel bad that they would have been extremely cramped in that command pod for so long..lol  Normally i would use Nukes on something of this size, but as mentioned above, i didnt have the tech at the time.  you cant see it from this picture, but there is a science pod on the decoupler of the command pod, simply to make life easier when pulling the science back in orbit.

Screenshot_2016_11_14_12_48_12.png

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  • 2 weeks later...

After getting bored in my career save, I decided to make a lander that was better than my best lander, Destiny 4 (scroll up) in as many ways as possible. So after quite a few attempts, I have created the fifth Destiny lander, which has much better general performance stats.

Xob60AM.png

 

It has more reliability, more ∆V, more comm. range, more docking options, more crew space, can be multi purposed as a cargo drop ship, small tug or a crew rescuer, MUCH more fuel (which means you can biome hop more compared to Destiny 4, which means more SCIENCE!), first person view isn't blocked by fuel tanks, KER instead of MechJeb, and it displays your space program flag clearly! There are many more improvements that have been made but I'm tired and don't feel like doing it. Hope you like it. :wink:

Edited by RedBee92
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