Jump to content

Low gravity is a b....!


technotica

Recommended Posts

Hi!

After having perfected my Mun landing and return I today decided to try a landing on Minmus, I had read getting to Minmus is harder but returning to Kerbin is much easier.

So after a few false starts having my approach too close to the planet I finally managed to get into an orbit around Minmus and approach its surface, surprisingly I had even more fuel left over at that point than on my trips to the Mun, I didn't even have to chuck my two atomic engines during the landing.

Everything was going beautifully:

TOyx2.jpg

Until I actually touched down, now I was landing on an incline (which I couldn't see this being the dark side of Minmus (which would make a great title for a novel)) but I was only going about 3 or 4 m/s at most at that point...

But this was the result:

hgRMi.png

I ended up bouncing, flipping around in the 'air' a few times while frantically trying to right my ship with everything I could think of (ASAS, RCS, main engine, button mashing).

I landed on the side twice, taking of into the air again each time and starting to flip again and then all my tanks exploded on the third contact.

So in the end I have a Kerbonaut , a command pod and 3 engines (which miraculously survived their tanks exploding) stranded on Minmus...

So what could I have done different? I had no sideways motion and my craft was approaching the ground reeeaaalllyy slowly.

Any tips?

Thanks!

Link to comment
Share on other sites

from my expiriance with minmus you need to land at lower than 1m/s to not bounce, the gravity is so low that even going 3 or 4 m/s you will bounce around like mad, also landing on the large flat areas is alot easier than on an incline

good luck

Link to comment
Share on other sites

Landing on the night side is always unadvised, for reasons you've just discovered....

Anyway, to help with the bouncing, try sticking three or four mini solid rockets upside down on your lander. Fire them on contact, and they should hold you down while the lander settles.

If the lander is light and you have a strong RCS, you can use that instead.

Link to comment
Share on other sites

Not sure if you have been doing it, but something that helps a lot with landings is an RCS module (with 4 manuever jets of course) and once you get close to landing, ensure you are vertical, engage SAS/ASAS with the RCS system turned on. Then when you land, even if you bounce a little, the RCS/ASAS will attempt to keep you upright. I find it generally works fine on most/all landings that are less than 10m/sec vertical and less than 4-6m/sec horizontal velocity and relatively flat. Add in much of a slope and it generally doesn't matter how slow you are going. Tipsville.

Doing the same is also pretty good for killing horizontal velocity or manuevering over the surface. You get down near the surface, engage ASAS/RCS and then use the RCS system for horizontal thrusting to building up some sideways speed and then kill it before landing. It is how I generally get within a couple of hundred meters of my other landers. Of course you also need to be tweaking the main engine occasionally to keep at a hover (easier the lower the gravity as as your fuel will last a lot longer).

Something I find that helps is adding in lights from one of the mods. Especially on the night side. In general though even daylight side you can see the lights on the ground somewhat. It helps you judge the real altitude better so you know when you are really close based on the spread of the lights.

Link to comment
Share on other sites

Even MechJeb struggles with landing on Minmus! You really need to land on a flat surface at 0.5 m/s or less otherwise the whole thing goes bollocks-up rather quickly (You have no idea how many times I have had to use the "PANIC!!" button on the MechJeb translatron module after a botched landing!). Another thing you have to remember is KILL HORIZONTAL VELOCITY! This has caught me out more times than uneven terrain.

Link to comment
Share on other sites

One of the good things about low-g landing areas is that if you feel your landing is going to fail, you can always floor the engines and abort the landing, to gain some altitude rather quickly. Giving you some breathing space or maybe even find a new landing spot.

Link to comment
Share on other sites

Landing on Minnmus is really that hard but there are some steps. First off never try to land on the dark side except when you are using Mechjeb (Which you weren't) or landing on one of the lakes. (Which you also didn't do) Try to land on the bright side as you can see how close to the ground by your shadow. Secondly never trust you altimeter under 20,000 meter. You probably know why. The easiest solution I can give you is to land on the lakes. This is harder said then done. Unlike the moon and opposite to what the wiki says Minnmus is not tidally locked to Kerbin. I have observed rotate on its axis from map view. Coming in from a high obit to and aiming for a lake will most likely mean you miss it before you land. Get into a nice low obit and you when a see a lake coming up burn retrograde to it. Try to land as softly as you can and try not to bounce. Keep RCS on as you land. It can help you kill horizontal speed as well as keep you upright it you start to tip over.

Link to comment
Share on other sites

I found landing on Minmus easier than on the Mun, thanks to lower gravity.

But yeah, you can't do much good when landing on the dark side.

I personally have a 6 legged lander. When I land I keep the ASAS on, and I bounce on the ground until it stops me.

landing on the side of a collin/small mountain helps a little if you come on the right side.

screenshot6.png

Link to comment
Share on other sites

Landing on Minnmus is really that hard but there are some steps. First off never try to land on the dark side except when you are using Mechjeb (Which you weren't) or landing on one of the lakes. (Which you also didn't do) Try to land on the bright side as you can see how close to the ground by your shadow. Secondly never trust you altimeter under 20,000 meter. You probably know why. The easiest solution I can give you is to land on the lakes. This is harder said then done. Unlike the moon and opposite to what the wiki says Minnmus is not tidally locked to Kerbin. I have observed rotate on its axis from map view. Coming in from a high obit to and aiming for a lake will most likely mean you miss it before you land. Get into a nice low obit and you when a see a lake coming up burn retrograde to it. Try to land as softly as you can and try not to bounce. Keep RCS on as you land. It can help you kill horizontal speed as well as keep you upright it you start to tip over.

Being tidally locked doesn't mean you don't rotate on your axis. In fact it necessarily means you rotate.

Link to comment
Share on other sites

I'd recommend MechJeb and using a combination of the Smart A.S.S. and Translatron computers. Just not the auto-lander. How I loathe the autopilot's behaviour (I find it to be very inaccurate). However, those two computers together give you many very helpful tools to control your descent rate (which I always find to be the most difficult part of landing by hand).

Using MJ and some floodlights, it's relatively say to softly touchdown at a location of your choosing, around a speed of 0.1m/s if you wish.

Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...