Landing Tips

[Steve Kerman]

This is where you browse for useful information for your planet/moon and some helpful tips to not die. Please share your own useful information, that would be so great!

Edited January 2, 2018 by Steve Kerman
Fix minor errors.

[SupperRobin6394]

*Takes deep breath*

Don't go and land at 300m/s if you're 150 meters above the ground because you totally didn't pay attention in your rescue mission to Minmus to rescue what's left of your lander which crashed because of the exact situation but slower.

Not that this ever happened to me, why asking?

Edited January 2, 2018 by SupperRobin6394

[Superfluous J]

99 Kerbals stranded on Mun

99 Kerbals on Mun...

Send a ship

to save them all

100 Kerbals stranded on Mun!

Edited January 2, 2018 by 5thHorseman

[qzgy]

Don't load a terribly laggy craft and leave for a while. Your lander will not exist by the time you get back.

[Geonovast]

12 minutes ago, 5thHorseman said:

99 Kerbals stranded on Mun

99 Kerbals on Mun...

Send a ship

to save them all

100 Kerbals stranded on Mun!

[Rocket In My Pocket]

Step 1: Hit hold retrograde.

Step 2: Burn engines on the way down.

Step 3: Profit?

[Geonovast]

57 minutes ago, Rocket In My Pocket said:

Step 1: Hit hold retrograde.

And make sure it's on "Surface" and not "Orbit".  Mine seems to have decided to stop automatically switching on me.  Trying to land on The Mun with Orbit retrograde is... interesting.

[Starman4308]

1 hour ago, Geonovast said:

And make sure it's on "Surface" and not "Orbit".  Mine seems to have decided to stop automatically switching on me.  Trying to land on The Mun with Orbit retrograde is... interesting.

You should also avoid target retrograde, even if the target is close. That's how my first rescue vessel tipped!

What is useful advice is not to obsess about a perfect, maximally efficient landing, and don't be afraid to use some upwards thrust to avoid terrain, even terrain you haven't seen yet. Perfect is the enemy of good and good Kerbals.

[Geonovast]

Also a good thing to use RCS for landing on low gravity bodies right before touchdown.  Tapping H give you much better fine control than tapping shift and hoping you hit X right away instead of Z.

Don't hit Z.

[Ty Tan Tu]

Geonovast makes a good point. 

You want to look at the navball at the bottom. Make sure it says "Surface" and is pointed straight up. Remember you have both a vertical and a horizontal speed vector. As you are going down getting close, the ground is going to give you visual clues. If the ground is moving left/right/up/down you can tip your ship ever so slightly off of center opposite to the ground's movement. Then re-center it to 90 degrees, straight up. This can take some practice because the keys will not always be intuitive because of the orientation of your ship. You might have to press "A" to go up or "S" to go left. Keep the vertical speed slow and this will not be a huge problem. Just nudge it in a horizontal direction. and then re-center it to straight up.

Glance at the display at the top to make sure your decent is not in the red (there is a little light at the bottom of the top display), but mostly watch the navball at the bottom.

After you crash, but your Kerbal survives, ask us about doing a rescue mission. That is what happened to me on my first attempt... 

[KerBlammo]

1 hour ago, Geonovast said:

And make sure it's on "Surface" and not "Orbit".  Mine seems to have decided to stop automatically switching on me.  Trying to land on The Mun with Orbit retrograde is... interesting.

I set an initial de-orbit maneuver node and auto-execute it.  By the time it is done its time to point retrograde and hand fly it down to the surface.  That way there's no confusion about the retrograde marker.

My problem usually is thinking "I'll land just past that crater" and then ending up landing on the steepest of said crater wall. Sometimes the only thing to do is give the engines a boost fly up a couple of 100m and land again.

[Tyko]

A couple of other points:

1. Make sure you're in Surface not Orbit or Target
2. The more steep the angle of descent the less fuel efficient your landing is, but the easier it is to judge your landing site and make correction. The fuel efficiency loss can be small, it just depends on the gravity of the body you're landing on. It's less efficient for the same reasons that launching straight up is less efficient than a gravity turn.
3. The lower your orbit the less energy you have to kill off before you land.
4. High TWR is really helpful. a TWR of 4 (within the gravity of the target body) or more gives you a lot of margin for error

With all that in mind, here's my process for safe and sane landings

1. Start at 100km orbit (or whatever is appropriate for the target body), this usually lets me time warp fast enough that I'm not waiting forever to get to my first burn.
2. on the opposite side from my landing zone I execute my first burn to bring my PE down to 15-20km over the landing zone
3. a quarter orbit ahead of my landing zone I execute a short burn to drop my descent path to just past my target landing zone - maybe 5 - 10 degrees past it. I also will make in minor plane changes here if my landing zone isn't exactly on the equator.
4. drop maneuver node just before you landing zone and plot a deceleration that puts on you on a 45 - 60 degree descent path. You want it pretty steep - again, this is a little less efficient, but gives you a much better chance of controlling your landing spot.
5. Execute the burn and as soon as it's complete, close the maneuver node, make sure you're in Surface mode and set SAS to Retrograde.
6. From there it's just a matter of riding your descent curve down and using thrust to brake.
   1. Using BetterBurnTime mod is great here because when you're in the terminal phase of descent it provides a readout telling you seconds to impact and estimated burn time. The estimated burn time is pretty conservative too, so it makes it easy to judge when to burn.
   2. A suicide burn - waiting to the last possible second and burning full thrust - is the most efficient, but really stressful and doesn't leave margin for error. I prefer to slow the craft down 100m or so above the surface and then creep down at 10m/s or so from there. If you're using RCS like @Geonovast suggested it's pretty easy to use RCS to scoot your landing spot around from there while essentially hovering on your main thruster.

 

Hope this helps!

Edited January 3, 2018 by Tyko

[DAL59]

22 hours ago, Steve Kerman said:

This is where you browse for useful information for your planet/moon and some helpful tips to not die. Please share your own useful information, that would be so great!

Have a separate ascent stage, so if the descent engine is destroyed at landing, you can return anyway.

Mun- There are lots of craters and mountains, so when you are flying low and fast, be careful.  Its important to be able to slow down fast enough to avoid the rims of craters.  

Minimus- Very easy, especially the flats.  Beware of the near-vertical cliffs surrounding the flats.  

Moho- Same as the Mun, but twice as much gravity.  You really might want two stages, or a lot of fuel.  Leave a mothership in orbit.

Eve- Very easy to land.  A few chutes and a heat shield will make you drift down gently in the thick atmosphere, but some parachutes will overheat.  You will need a very large, probably 3 stage rocket to get of Eve, especially if you launch from sea level.

Gilly- No effort or danger needed.  You can literally jetpack down to the surface and back.

Ike- Like the mun, with 2/3 the gravity.

Duna- Thrice as much gravity as the Mun, and a thin atmosphere.  It is not thick enough to lower you to the ground with parachutes, you will still need some fuel to slow down your landing.  Its only thick enough for drogue chutes to be effective.  I recommend several.  The air is not thick enough to require fins or difficulty during ascent, just wait a little bit before starting gravity turn.  If landing from low orbit, you don't need a heatshield.  

Dres- Does not exist.

Jool- With a ridiculously large rocket, you can descend into the air and return, but past a certain point you will explode.

Vall- Like the mun but without mountains or craters to worry about.

Bop- Same as gilly but bigger.

Pol- Same as Gilly but bigger.

 

[Fearless Son]

A few things to keep in mind at the design stage of a lander:

I cannot stress enough how important having a low center of gravity is.  A lander that is tall and top-heavy easily falls over on landing.  You will almost always have some amount of horizontal velocity, even if minor, and the higher your center of gravity is the more the horizontal velocity can literally lever it over.  

Equip your lander with lights pointing down.  These are absolutely essential for landing during night time, but more commonly even during day time they give you an excellent sense of how far off the ground you and how level your craft is relative to the surface at a glance.  The altimeter is a good approximation of your height, but it rarely takes bumps in ground elevation into account, so you will have to be able to count on the mark one eyeball to prevent a tragic miscalculation, and the lights help.  

[Tyko]

16 hours ago, Fearless Son said:

Equip your lander with lights pointing down.  These are absolutely essential for landing during night time, but more commonly even during day time they give you an excellent sense of how far off the ground you and how level your craft is relative to the surface at a glance.  The altimeter is a good approximation of your height, but it rarely takes bumps in ground elevation into account, so you will have to be able to count on the mark one eyeball to prevent a tragic miscalculation, and the lights help.  

If you're using KER it includes a readout of the slope at your target landing point - this is really useful. I actually built a small custom window - positioned right above the Navball that reads out slope, vertical velocity and height AGL. This places all my key metrics together at the bottom of the screen and makes landing a lot easier.

[Deprastronaut]

To help with flight axis orientation in a vertical standing lander, I instal a command control module facing horizontal and aligned with the lander window. This made my landings a hell of a lot easier. I'd much rather manually land than to press retrograde hold.