Which kind of Landers?

[Kroslev Kerman]

What type of Landers do you like Multistage or Single stage vote!

Edited November 24, 2018 by Kroslev Kerman

[jlcarneiro]

I don't have much time to play and, due to restarting every new version, never got much away from Kerbin SOI.

But everytime I can, I design a lander with a lighter ascending vehicle...

[Geonovast]

Generally SSTO, unless I'm feeling recreation-y.

[Xurkitree]

I like Single Stage ones, but I'm willing to make an exception for Eve.

Heck, I have an Ion Lander that can land on Vall and return to orbit.

[magnemoe]

Lander is single stage, I however has an interplanetary ship in orbit. 
If its an base who is landed this tend to be an tug and base, here an fallback procedure might be to use the tug as an crashing stage else tug is saved for later uses, put an capsule and lots of sience gear on an docking port and dock to tug with landing gear and you have an 4-5km/s science lander to jump around with. 

Eve has to be multi stage, Tylo can be single stage if you refuel both on ground and in orbit or have ISRU. 
Layte and space planes works very well again you can use ISRU or refuel in orbit. 
On all the three places bases are just landed 
You can use an drop stage for bases on Moho and Vall but you want some fuel capacity anyway. 

Edited November 24, 2018 by magnemoe

[Guest]

6 minutes ago, magnemoe said:

Eve has to be multi stage, Tylo can be single stage if you refuel both on ground and in orbit or have ISRU. 

I made a fully recoverable, crewed Tylo lander without ground refueling or ISRU. 

Whether it counts as single-stage or not is, I think, a matter of debate...

[Gargamel]

Unless you have a specific goal in mind, ie recreation or mission specific design requirement, I think it's pretty pointless to have a multistage lander for low gravity bodies.  I don't think it's worth the complexity and added part count for extra stages.  

There's also the whoops factor.   If you miscalculate something, or need to burn extra fuel earlier in the mission, a multi stage lander will require you to abort back to orbit if you run dry on the landing stage.   And don't argue that you can ditch your landing stage, land, and then return to orbit with just the ascent stage, if you could, you wouldn't have needed a multi stage craft in the first place.    With a single stage lander, you will still be able to land and launch to orbit, where a rescue/mothership can come get you, without losing the mission goal.

Note, I'm not arguing against stages that are staged away prior to landing.  I do this often, a nice low TWR/ High ISP stage for transfers and de-orbital burns, which gets staged after completing the de-orbit burn, even if it has some fuel left in it.  Let's me start my dV budget anew. 

[magnemoe]

1 hour ago, Gargamel said:

Unless you have a specific goal in mind, ie recreation or mission specific design requirement, I think it's pretty pointless to have a multistage lander for low gravity bodies.  I don't think it's worth the complexity and added part count for extra stages.  

There's also the whoops factor.   If you miscalculate something, or need to burn extra fuel earlier in the mission, a multi stage lander will require you to abort back to orbit if you run dry on the landing stage.   And don't argue that you can ditch your landing stage, land, and then return to orbit with just the ascent stage, if you could, you wouldn't have needed a multi stage craft in the first place.    With a single stage lander, you will still be able to land and launch to orbit, where a rescue/mothership can come get you, without losing the mission goal.

Note, I'm not arguing against stages that are staged away prior to landing.  I do this often, a nice low TWR/ High ISP stage for transfers and de-orbital burns, which gets staged after completing the de-orbit burn, even if it has some fuel left in it.  Let's me start my dV budget anew. 

For early missions you can just as well stage, I always do, unless you can refuel an SSTO is pointless. I tend to use the four radial tanks with legs around engine on center stage and capsule on top. 
Land  

You can have an  SSTO with staging, this however is an abort system, just had to use it on Minmus. You dump legs fuel tanks, power and various extras. I aborted to orbit as I was on an ballistic trajectory an MJ said I was 30 m/s low on fuel, was also to low to raise Pe to orbit so ejected stuff and orbited. 
 

 

 

[Aegolius13]

For anything smaller than Duna / Tylo, the dv requirements for a round trip are small enough that there's not much point to staging.  Plus once a support infrastructure is set up, it's nice to have fully reusable landers, which of course requiers SSTO.  

However, if I'm doing a direct ascent style mission, sometimes a break between stages will occur during the "lander" phase of the mission.  (E.g., one stage might do the munar insertion and injunction burns, land, take off, and then a second stage might complete the ascent and return to Kerbin).  

 

[Kroslev Kerman]

well i usually like Multistage landers so i dont need to worry about if my lander has enogh fuel to get into orbit

[Sharpy]

Since I overengineer everything, I design multistage landers, then perform the transfer and braking burn with my core ascent stage, land on the engine of the transfer stage, and use the descent stage to soften the landing on Kerbin.

[SchwinnTropius]

22 minutes ago, Sharpy said:

Since I overengineer everything, I design multistage landers, then perform the transfer and braking burn with my core ascent stage, land on the engine of the transfer stage, and use the descent stage to soften the landing on Kerbin.

You do that too? I do it usually as an accident. As long as the budget permits, why not overengineer?

[Pecan]

After first Mun landing I don't do one-shot missions, therefore everything is reusable infrastructure.

[RealKerbal3x]

When I first landed on the Mun I did an Apollo-style mission, so I had to use a two-stage lander. However, single stage landers are a lot more practical. They're also pretty much essential for a surface base where you need to transport Kerbals back and forth from the surface.

[Foxster]

There wasn't a "both" option. 

If it's somewhere like the Mun then I find it hardly worth having multiple stages because a little craft that can land and return to Kerbin can easily do this in one stage, though it might include a non-dV disposable science stage:

For further planets and moons, especially those with a bit more gravity, a multi-stage lander is usually needed. I tend to prefer not to bother with Apollo-like missions because of the tedious nature of docking and so I often make the lander capable of Kerbin-return too (not at Eve, ofc). 

 

[Tyko]

Unless I'm intentionally doing a recreation I use SSTO landers and lunar rendezvous for landings. Even at 3.2x scaling I haven't found the need to stage off lander parts.

I typically send my lander and an extra fuel supply unmanned to lunar orbit then send a second crewed mission to dock with the lander/fuel depot. Once the landing is complete the lander stays attached to the depot ready for the next landings.

When I have done 2 stage landers I followed @magnemoe's approach of using only one center engine and jettisoning radial drop tanks, landing legs, depleted experiments, etc. This offers a safety benefit because I can use my ascent fuel in an emergency if descent goes horribly wrong. 

[Snark]

Quote

on the mun or ike or those low gravity no atmos moons/planets

Virtually always SSTO, mainly because such moons/planets generally have such a low escape velocity that I don't need multiple stages.

Occasionally, if I have a lander that I'm planning to do a lot of biome-hopping, I'll make one that has some "drop tanks" to boost total available dV, so I'll go with multi-stage in such cases.  But those tend to be more the exception than a rule-- if I really want to do a lot of biome-hopping, I'm more likely to leave most of my fuel supply on an orbiting station, and go back there to refuel in between hops.

About the only time when I absolutely need a multi-stage lander is on Tylo.  But I find Tylo such an un-fun destination that I hardly ever go there-- I mean, I went there a few times just for the challenge and variety of needing a lander that's both high-dV and high-TWR... but once I'd done that a few times, it has such a low interest-to-hassle ratio that it's just not worth my while to go there.

 

[Cavscout74]

I usually do single stage landers except fairly early career, I use a two stage lander for Mun/Minmus where the lower stage keeps a probe core, solar panels & science gear to make it easy to do the "gather science from surface of _____" contracts.  Typically that design only gets used twice, then I switch to single stage for simplicity.

One of my typical multistage landers on Mun.  It uses Modular Rocket System tanks, where the lower forms a ring around the upper stage, using the same engine to power both.  When you stage off the lower, the upper slides out of the ring & goes on its way.

 

 

Edited November 28, 2018 by Cavscout74

[Zosma Procyon]

On 11/24/2018 at 7:32 AM, jlcarneiro said:

I don't have much time to play and, due to restarting every new version, never got much away from Kerbin SOI

You know you can copy-paste your saved game from one installation to the next, right?

[Zosma Procyon]

I use multiple stages to get the lander to its destination, and even multiple stages to get it back into orbit; meaning I jettison the landing legs on liftoff. And I also usually leave the lander's engine behind when the mothership leaves to return to Kerbin.

[jlcarneiro]

3 hours ago, Zosma Procyon said:

You know you can copy-paste your saved game from one installation to the next, right?

Yes, yes, I know, thanks! 

I did that in the beginning (to keep the improved kerbanauts) but I had some kind of problem (don't really remember what) and stopped doing it... 

[razark]

53 minutes ago, jlcarneiro said:

I did that in the beginning (to keep the improved kerbanauts) but I had some kind of problem (don't really remember what) and stopped doing it...

I also tend to restart each version (or whenever I add a significant mod), and haven't spent much time at all beyond Kerbin SOI.

 

My landers tend to be multistage.  The first stage tends to be drop tanks, mounting legs, lights, and science bits enough for two or three biomes.  I'll land, get all the science, reset what needs reset, hop to the next, etc.  Once I'm done, the side tanks are jettisoned and the core performs the return trip.  If I ever do any missions beyond Kerbin local, I'll probably re-evaluate my strategy.

[Xurkitree]

I didn’t realise that several people don’t go interplanetary...

[Cavscout74]

54 minutes ago, Xurkitree said:

I didn’t realise that several people don’t go interplanetary...

From what I understand, it's actually pretty common not to go past Minmus.  The difficulty (& time involved) jumps up substantially once you leave Kerbin's SoI, especially if using a pure stock game. 

[Pecan]

17 hours ago, Xurkitree said:

I didn’t realise that several people don’t go interplanetary...

Past polls/discussions have tended to show that very few people (10% or so, if I remember correctly) make many, if any, interplanetary trips.  There's the transfer-window and time issues plus it can be pretty scary with nothing in the sky but the sun.  Kerbin SOI is a lot of fun even when you do go further :-)