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dimovski

Mun...

Question

im sorry for opening yet another thread , but currently im really frustrated with the Mun , this time i just spinned on my 8 landing legs at 30 m/s , and when the command pod touched with these 30 m/s the ground it exploded, after which all other parts exploded aswell... anyone to give me a hint (i dont really need help with the orbiting method, i just go straight up and wait for a mun intercept (i dont really care if its going to slide 10-20km just to get to the mun, if it does :) )?

PS: my rocket : Chute

Mk 1 Command Pod

T18A

ASAS

Brand Adapter

Rockomax X-200-32 (radially mounted 8 landing legs , and 8 LV-45Ts each with 800l fuel)

Poodle

Brand Decoupler

X-200-32

X-200-32 (radially mounted 8 LV-30Ts with 800l fuel each)

Mainsail

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30 m/s is too fast.

Single digits at least. I aim for sub 1 m/s

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Yeah, that's over 3 times the maximum safe contact speed, but also, it sounds like your lander is REALLY heavy: so heavy that it's gonna go squish at even lower speeds than that. You'll find that while it takes a really big rocket to get off of Kerbin, a little bitty one is enough to get back from Mun because you're not fighitng atmosphere and heavy gravity on the up, and Kerbin's atmosphere actually helps you on the way down.

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Yep, think Apollo. Whacking great roman candle to get to the moon, tiny little firecracker to actually land and return. You used to be able to return from the mun's surface just using the little control jets, but I'm not sure that's still possible.

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hmm,so additional orbital stage with the atomic rocket ? oh ,Mk 1 command pod, or Mk-1-2?

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hmm,so additional orbital stage with the atomic rocket ? oh ,Mk 1 command pod, or Mk-1-2?

Doesn't really matter much, even with the heavier command pod you only need a couple of 400L tanks and the little 909 engine to get back to kerbin.

Your lander is much heavier than it needs to be but it's nowhere near heavy enough to cause landing problems, the problem is the speed.

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If you want an example of a Mun capable rocker

scaled.php?server=248&filename=screenshot8yj.png&res=landing

i use one seat landers for this one. Each one is made of mk1 pod, parachute, LV-909, half-tank, and 3 legs. Each one can land, take off AND return to Kerbin. With fuel to spare.

As for your methods, well I believe they need a bit of refining. Try getting into a parking orbit first. I find it helpful to also have a dedicated Trans-Munar Intercept (TMI) stage.

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holy ***** , and this works ? :o :O

wow, if i knew how great that LV-909 is... WOW... so ,now im orbiting the mun with 500 m/s ,Ap 14,000 m (not km, meters), Pe is 12,000 and with 250l fuel left, hmm... will try to figure out what to do now (no fun having it said , to me atleast :) )

Edited by dimovski

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The LV-909 is an average engine but the reason to use it is the weight. When you've got 0.8 tons of pod and 1.125 tons of fuel the difference in the range you get from a 0.5 ton engine and a 1.5 ton engine is massive.

AmpsterMan's ship is a good example of a medium sized Mun lander but smaller is definitely possible. In fact the limiting factor is not the amount of fuel but the large individual parts - fuel tanks half or a quarter of the size of the current smallest tank would let you drive the weight down further.

Edited by EndlessWaves

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Just shorten up your lander a little bit. Instead of the X32 fuel tank, make it an X16. Drop the radial mounted engines.

1NXH0.jpg

The interesting thing is the T:W is high enough to practice taking off and landing on Kerbin. Try it out. Just turn on the ASAS, and liftoff higher than the launch tower, then try to land safely. Turn on the fuel cheat too (since it's just practice) and keep trying it higher and higher. A general rule of thumb is never land faster than 10m/s. You ideally want to get it down to 1m/s just before you land.

That lander in the photo has about 3200m/s of delta-v. That is actually enough fuel to do the TMI, land, and return to Kerbin if you practice your landings so you don't waste too much fuel. You can gain another 200m/s of delta-v if you drop the legs down to just 3, which is fine for landing on the Mun. Or, you can change the poodle out for the Lv909 engine. The poodle has a lot of thrust and gives this craft a T:W of like 9 when on the Mun. The Lv909 would give it about a 2.5-2.6 thrust to weight ratio on the Mun but it would up the Delta-V to around 4500. That is a godly amount of fuel for landing on the Mun or Minmus.

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well , i did managed a low orbit , 10km around the mun already with this, huh guys thank you a lot for your help, that LV-909 tip was priceless, didnt knew its so good :)

thogh theres one question left... is it even possible to bleed all my speed from some 550 m/s at a height of 14,000m ? because it seems that my fall on the ground of the mun,the 1st time, was pretty slow in terms of falling, but i probably had some naughty sideways slip... hmm, ill try to find something, really hooked on this game already :)

EDIT: i managed to land on it ( though i was so nervous i havent looked at my retrograde very often, which resulted in losing all my 250l of fuel on the braking part , and i acctually got out of fuel and splashed with some 20-40 m/s on it... but everything survived... also, i did the noobish thing of leaving my RCS on in the ascent stage... wouldve helped a lot to get the landing straight... oh well...) ,shortly after that i tried to escape the mun with my 1st rocket in orbit around it, so, with 600l for the poodle, i just barely managed to shrink my periapsis from 11 millions to 0 , and my apoapsis was acctually outside of minmus :o so i fell down into the atmosphere with 3000 m/s and braked some 500-600 m/s with 200l of the fuel left... huh ,was fun :) cant wait to get better in the game :) )

Edited by dimovski

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10km is a bit low to go for a landing. I usually start my landings from a 40 or 50km orbit.

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I land using a parking orbit of around 4000m-5000m (less if I can get away with it), as I believe Mun's highest feature is around 3400m. This has served me well on my many Munar missions. I find it much easier to kill my lateral movement than fight the forces of gravity (I believe this is for the same reasons that making a gravity turn during ascent is more efficient).

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Slow down until your descending ~ 5m/s and on the final 100-200 meters, use your RCS thrusters to maintain your speed and to fine tune your landing. If your pro, you can use your main engine, what ever it be. Just be careful with that as it is really easy to go a wee bit too fast and you start ascending again.

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I just managed to land a 3-person lander on Mun myself and as usual I find the biggest challenge is cancelling out my horizontal velocity before I'm actually encountering the surface terrain. I can't tell you how many times I've pulled an Apollo 11 and ended up going straight left to right across Mun's surface and when that happens I typically have no clue what to do about it. Small changes in acceleration and orientation in that circumstance tend to be quite magnified and usually I end up with an exploded lander. Thus far my best landings have been the ones where I really do come more or less straight down and encounter the ground at 3 m/s or less - under those circumstances my success rate has been 100%.

There are a couple of things I wanted to bring up though. I've actually encountered a problem where my legs have clipped into the Munar terrain and knocked the engines off my fuel tanks. This is obviously a very bad thing and I'm curious as to whether or its a bug or some sort of feature. I'd also like to know if anyone can point me in the direction of just what the impact tolerance ratings mean for individual ship parts. The capsules seem to have a much higher figure than most of the other stuff, and I guess that makes sense, but I could use a better understanding of just how much force, say, landing gear can take before exploding or breaking off. Still having fun though despite my poor landing-record.

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Jean, the best way to fix this is to burn your retrograde all the way down, it's tricky, but it works.

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Try to cancel out horizontal velocity as high up as you can. It's easy if you look at the nav ball:

- Zero horizontal velocity is when the yellow retrograde marker is smack in the center of the blue part. This means you are going straight down.

- Try to keep your ship pointing straight up, as much as possible.

- When you are at a high altitude, burn retrograde so that your trajectory on the map is as vertical as possible when it intersects the ground.

- When you are retro firing, half way down, aim your ship so that it is beyond the yellow marker. This will push the yellow marker towards the center.

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There are disadvantages to coming straight down. You can't tell the slope of the ground below you until you're on it, for one thing. Also, your vertical speed tends to build up rather quickly.

I like to come down on a curve that gradually approaches vertical as I do several burns directly to retrograde, reducing both speed vectors (vertical and horizontal) at the same time. Also, I'm not sure how to describe this, but this approach means that the surface of the target world is curving down away from me as I approach, effectively reducing my descent rate. You end up burning the same amount of fuel, of course, but it's spread out over a longer time, making the whole process less hectic and more controllable. Looking past your ship at about 45 degrees down, you can also get a pretty good idea of where you're going to come down, and it's fairly easy to make adjustments to the landing point. You can even pretty easily abort that landing spot simply by burning straight up, putting yourself on a sub-orbital arc to another spot altogether. But these are just matters of personal preference and style of play. There's no one correct method.

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Well Nibb31 I've been trying to do what you're suggesting however I find KSP's controls when it comes to landing abysmal at best - or, maybe I'm doing it wrong, or some combination of the two. I've mentioned this I think before, but I don't see how one can effectively use the WASD keys, and hit left control/shift and use the mouse to change and reorient your view all at the same time. I also find my ship is constantly tipping over, rotating, listing in various directions even if I apply no thrust at all, and this is (as I said) very much magnified when you're 10 meters off the ground.

By far my typical failure mode is to reach the ground, hit between 3-6 m/s upon one of my struts, which is enough to push the whole craft on its side. As the craft falls over, I have no means to arrest that, usually anyway - though I do sometimes manage to escape and abort to safety. The new rocket designs I've been using have allowed me to reach Mun with a Sizeable reserve of fuel, often 1500L+ and a Poodle engine to slow me down. This has been quite effective at putting payloads of 10-15 mass units (tonnes, I guess?) on the surface and often I can cancel out all my velocity above 10 Km height, I've found that if I do that and "fall" towards the ground that the craft tends to right itself due to the gravitational attraction and when it works it's worked quite well. Like Vanamonde said however it's not ideal, in the sense that you can't really tell the general relief of the ground your falling towards.

I just think I might not be very good at the quick reflexes and proper button mashing component of the landing process, but learning more about the game has helped. It is still quite satisfying to reach the ground and not end up meeting a fiery death. Actually have four Kerbals on Mun at the moment myself, that's a first for me. I do wish they'd get some new, modern tutorials up on YouTube as well - most of the stuff I'm seeing is from like pre-0.13 era.

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I'm going to recommend the 'come in low and fast' approach' too. I set my periapsis around 5,000m and begin the retrograde burn just after. It's perfectly do-able to come in lower, but I used to start my descent at something silly like 80,000m, and I guess some of that hesitation remains. One of the benefits is that if you do it right, you'll cancel your horizontal velocity and only have a short distance left to descend. That means using less fuel, and it's quicker too.

Jean, the controls can be a bit touchy, especially if your lander is small. I recommend using precision mode (capslock) if that's what is causing the problem. Also, I remapped the throttle up/down keys over to 'p' and semicolon, so I can use left hand for steering and right for power. Another thing to mention is that once you've more or less confirmed that you're headed for more or less flat ground, all of the flying is done with the nav-ball. You'll be moving around in all directions, probably rotating as well, so the camera view is pretty useless apart from checking how far it is to the surface.

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"this time i just spinned on my 8 landing legs at 30 m/s"

Yeah, you ploughed your ship into the ground at nearly 70mph...

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I'm going to recommend the 'come in low and fast' approach' too. I set my periapsis around 5,000m and begin the retrograde burn just after. It's perfectly do-able to come in lower, but I used to start my descent at something silly like 80,000m, and I guess some of that hesitation remains. One of the benefits is that if you do it right, you'll cancel your horizontal velocity and only have a short distance left to descend. That means using less fuel, and it's quicker too.

Jean, the controls can be a bit touchy, especially if your lander is small. I recommend using precision mode (capslock) if that's what is causing the problem. Also, I remapped the throttle up/down keys over to 'p' and semicolon, so I can use left hand for steering and right for power. Another thing to mention is that once you've more or less confirmed that you're headed for more or less flat ground, all of the flying is done with the nav-ball. You'll be moving around in all directions, probably rotating as well, so the camera view is pretty useless apart from checking how far it is to the surface.

Good advice there on switching over to p/semicolon or some equivalent: I'll need to try that myself. I'll also agree that the nav-ball is far more useful going down than looking at the ship or the terrain (well at least until the last few meters) - I actually find looking at what's happening in real time to be a bit confusing, it's just far easier to maneuver by aligning myself with the ball than trying to figure out 3D spatial orientation on sight. As for Capslock, yeah I use that all the time. I probably wouldn't be able to land at all without it.

I think I see your point about descent from a high orbit, well at least high in KSP terms. I'll have to see about giving that a shot as well, can't hurt to try something new. Oh, as for craft weight: I've landed three-man capsules on Mun with a lander mass of nearly 15 tonnes - I've also done the same with much smaller spacecraft, one of which came in below 4 tonnes. I can say that the heavier versions are much more tolerant of impacting the ground at slightly higher speeds and seem less prone to translating minor mistakes into full-on catastrophic failure.

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Honestly, I find that switching to the IVA view on the properly equipped pods does me a WORLD of good for landings! I haven't had a hard landing in some time, due to the ease of finding the touchdown point -exactly- with the radar altimeter. Also, I altogether stopped looking at the lander and misjudging my vectors now that I -can't- see the lander!

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