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I need help at my landers


corporelax
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Make them squat and wide. You don't want a tall, thin lander, because that can tip. The lower and wider it is, the more stable it is.

Depending on where you're trying to land, a two-stage lander could be appropriate. You don't need the landing legs or equipment like that to get back to Kerbin, so you can jettison them when you go back to orbit. 

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As no info is provided, i give you some general hints for atmosphere-less planets.

 

Start with a light lander, dont over-engineer. Keep that for later landings.

When going back to orbit, leave everything behind, that does not need to get back into orbit.

Protect your crew. Use a cabin!

Make landers useful. Give them the option to carry equipment, vehicles or other things.

The heavy end goes down first. Put the heavy stuff on the lower end of your lander.

Add a docking port or probe core on the top, so you can control the vertival movement more easy.

Add lights to illuminate the landing area. Craters can be... very dark. Dont forget antennas, ladders and solar panels.

When landing, go in from low orbit and use a shallow descend trajectory. That helps saving fuel.

 

I hope i provided something useful. If you have specific questions, feel free to ask.

 

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In addition to what the others said, you should also plan an appropriate TWR. Keep in mind the gravity of the body you're going to land on (a TWR of 2 on Minmus would be a TWR of 0.1 on Kerbin...). Depending on your landing skills and on the terrain you're going to land in, you'll want different TWR values. If you are doing an extremely efficient landing in a flat area, where you first decrease your orbit's radius so it's just slightly above the ground, and then decelerate by burning nearly retrograde, but also enough towards the ground to keep your altitude, then a TWR of 1.2 to 2 should be sufficient. If you land the same way I do - the wasteful but easy way of first decelerating at high (~10 km) altitude, and then keeping the descent rate under control by regular burns, you might want a TWR that's clearly above 2, so your burns don't end up being horribly wasteful (if I'm not mistaken efficiency for vertical burns should be gif.latex?\frac{\mathrm{TWR}-1}{\mathrm{).

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For an early game mun/minmus lander I use a Mk1 pod with a decoupler, tank and terrier under it, and then 3 more tanks on radial decouplers with landing gear on the tanks.  This might be a shade heavier than other designs but gives a nice wide base to make landing easier. You can manually transfer fuel without needing fuel lines (select all 4 and then transfer in to the central one to avoid moving the centre of mass off the centreline), and dump the additional tanks to save weight on the way home.  You need around 2500 dv to get to from a low Kerbin orbit to the Mun, land, and get back, so either have enough fuel to do that or have an additional tank and terrier on another decoupler in the centre as a transfer stage

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For you first landings the flats of Minimus are the easiest possible. 

Use the nav ball well. Setting the SAS to retrograde really helps kill the horizontal velocity so long as it's set to surface. BUT don't fully kill vertical decent as that means you are going up and the retrograde SAS will flip your lander around to compensate. So long as you avoid that, retrograde SAS really helps landings. I land long narrow rockets easily so long as I'm on a flat enough surface. 

 

Speaking of long tall landers, if you are going to the flats of Minimus, I use from the top down the command pod, material bay, service bay with science and batteries, decoupler, 400 tank and 909 engine.  Add landing legs and parachutes to taste.  This assembly will land and get back to Kerbin.  However it's top heavy so be careful of the landing slope.

 

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1 hour ago, RizzoTheRat said:

For an early game mun/minmus lander I use a Mk1 pod with a decoupler, tank and terrier under it, and then 3 more tanks on radial decouplers with landing gear on the tanks.  This might be a shade heavier than other designs but gives a nice wide base to make landing easier. You can manually transfer fuel without needing fuel lines (select all 4 and then transfer in to the central one to avoid moving the centre of mass off the centreline), and dump the additional tanks to save weight on the way home.  You need around 2500 dv to get to from a low Kerbin orbit to the Mun, land, and get back, so either have enough fuel to do that or have an additional tank and terrier on another decoupler in the centre as a transfer stage

It's nearly 1200 m/s for the transfer from LKO to the Mün, and a little more than 300 m/s to get back. Takeoff at the Mün needs nearly 600 m/s, that leaves about 400 m/s for the landing. Wait, wat?

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If you have SAS set to retrograde make sure you have your fingers on the "X" and "T" keys and hit them as velocity approaches zero.  Recently, I've wimped out and done a four-stage landing procedure:

1) use manuever nodes to just graze the surface

2) retro burn using SAS [and speed set to surface] as low as I dare (computing the height for a suicide burn shouldn't be hard: compute the time it takes to kill horizontal speed, determine how long it takes to fall that far, burn at that height.  Haven't used this, but its a thought.  Kerbal engineer's suicide burn will kill you if you are going sidways)

3) suicide burn (using Kerbal Engineer) to some low ceiling (100m?)

4) manually land the final approach.  Note that you should be high enough to zero out any remaining horizontal motion, but low enough not to waste too much fuel slowing down.

And yes, TWR is your friend.  For something like Minmus a TWR of 10 or more makes much more sense than 2.

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Beware - if you land on the dark side of a body, you will be dependent on battery power, if it runs out its game over.

You will likely have solar panels, make sure at least one of them can point upwards from the ground, in landed configuration, to avoid the previous problem even daylight.

When landing, you may need some "hover time" in order to choose your landing site. The amount of dV that this needs depends on the gravity on the target body. The translation is easy - if the gravity at the surface on a body is 10m/s2, then you need 10m/s dV per second of hover.

I dont know how you feel about MechJeb or Engineer, but both can provide you with telemetry useful for landings.

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Get Engineer Redux (mod)

It is a simple mod and does not add parts (except little circuit boards that you put on your ship for information readouts) and does not hurt the game in a cheating manner through application of auto-pilot or anything. All it does is tell you your rocket stats when building.

It provides a window that tells you everything from available detlaV to weight, and does so per stage. More importantly, it tells you your TWR (thrust to weight) ratio. Basically, if you are above 1.0 on TWR, you can move away from that celestial body. Even better, the mod allows you to see your TWR in relation to the different planets. 

This way, you can make the best lander for a planet and not guess which engine to use, accidentally ending up either with a rocket that can't leave that planet or one that is far too powerful for your purposes and ends up using too much fuel, making it impossible to make it home.

 

HOWEVER:

I do suggest you make some without the mod, first. You can fly them around Kerbin if you want to understand the basics, even take one to Minmus (pretty much anything can lift off that moon). Then, use Redux to perfect. 

Redux doesn't ruin the game, but it does slightly rob you of the introductory experiences since it is, in a way, a cheat sheet.

Edited by Friend Bear
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5 minutes ago, Friend Bear said:

HOWEVER:

 

I do suggest you make some without the mod, first. You can fly them around Kerbin if you want to understand the basics, even take one to Minmus (pretty much anything can lift off that moon). Then, use Redux to perfect. 

Redux doesn't ruin the game, but it does slightly rob you of the introductory experiences since it is, in a way, a cheat sheet.

Friends don't let friends KSP without KER.

I can often be a KSP purist, in terms of mods, but KER is the instruments/math you should already have.

(And this is coming from the founder of the "Joe E. Napalm, Esq., School of Grip-It-N-Rip-It! Spacecraft Design" where top honors are awarded to those who can just eyeball everything.)

-Jn-

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3 minutes ago, JoeNapalm said:

Friends don't let friends KSP without KER.

I can often be a KSP purist, in terms of mods, but KER is the instruments/math you should already have.

(And this is coming from the founder of the "Joe E. Napalm, Esq., School of Grip-It-N-Rip-It! Spacecraft Design" where top honors are awarded to those who can just eyeball everything.)

-Jn-

Exactly why I am comfortable using it. 

 

If you really want to simulate reality, send a probe to do science on a planet, then start using KER (Redux) to build according to that planet. That way, you can say you did the necessary calculations to have that data.

 

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35 minutes ago, soulsource said:

It's nearly 1200 m/s for the transfer from LKO to the Mün, and a little more than 300 m/s to get back. Takeoff at the Mün needs nearly 600 m/s, that leaves about 400 m/s for the landing. Wait, wat?

I had it in my mind it was about 800 to the Mun, but I think I forgot about the circularisation burn, D'Oh.  So yeah, maybe closer to 3000

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Oh. Bring some of the small focus lights and point them straight down. Can save your but in a night landing. Rather than having to burn all the way at 5 m/s which wastes fuel, you can come down a little faster. Gives you about 200 meters of warning and helps you visualize the landing without needing to know the hard deck. The two spotlights start wide and diffuse and will tighten up and come together as you get close. 

Prior to this method I've lost a few craft due to "I didn't know the ground was at 4000 meters..."  

If you have a nearly spent transfer stage, I often finish it off in the final landing burn then use its drop to get a rough approximation of the distance to the surface  

 

Also when using the maneuver nodes pay attention to see if your trajectory intersects with crater edges and mountains before you get to your target THEN remember the planet/moon is rotating. I've done some low angle approaches and prematurely "landed" before even reaching my start of burn. 

Edited by tranenturm
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1 minute ago, tranenturm said:

Oh. Bring some of the small focus lights and point them straight down. Can save your but in a night landing. Rather than having tore end all the way at 5 m/s which wastes fuel, you can come down a little faster. Gives you about 200 meters of warning and helps you visualize the landing without needing to know the hard deck. The two spotlights start wide and diffuse and will tighten up and come together as you get close. 

This is good advice, the WWII Dambuster raids used this method to fly low over water, with the beams converging at a set height

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When having the pilot hold retrograde during a landing,he will stop when there is no "retrograde" direction for a moment. He should switch back to the standard of holding orientation. Just... don't come down too fast?

I haven't done many powered landings in 1.0.5 (lost saves keep setting me back), but that "bounce flip" idea hadn't occurred to me, and I've had no issues at all with my Mun landings holding retrograde.

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1 hour ago, Tfin said:

..."bounce flip"...

I can hardly remember how I used to do things before MechJeb...anyway, MechJeb has an "UP" hold function which I use a lot on landings. Helps a lot with hovering too, as you can "tip" your craft in a direction you want to go in and you will start to drift that way - release and you return to vertical. This goes very well with one of the vertical-speed-control mods.

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