100% stock Mun mission designs and .craft files (version 0.13.x and 0.14)

[BillWiskins]

Aha, right, well this does seem to be a thing which will help me. Thanks a lot - I\'ll put it into practise on poor Meredith 12 when I get home later. I may even upload a .craft for your wobbly spacecraft enjoyment.

[semininja]

Reading through this thread, I can see that the community has gained a valuable member in closette here. It\'s nice to see someone relatively new to the forums who\'s actively helping other users and who provides meaningful, constructive assistance when possible. I hope you are planning on sticking around.

On topic from a page or two ago:

There\'s one spanner in the works here, in that your initial formula T-W=D is only true if acceleration=0, like this:

?F=T-W-D=ma=m(0)=0 => T=W+D => T-W=D

Since a?0, you have to account for m and a as well...

?F=T-W-D=ma => T=W+D+ma => T-W-ma=D

...which unfortunately gets pretty ugly.

[Kosmo-not]

In that equation, I\'m solving for when the craft is in an equilibrium state. There is no net acceleration due to the fact that air resistance isn\'t allowing the craft to go any faster.

[closette]

@semininja, thanks for the kind words, but others on this thread have done most of the work! The Excel file provided by Kosmo-not was a tour-de-force of data collection

I too have been wondering about the 'fuel efficiency' equation assuming zero (or perhaps just a small compared to 'g') acceleration.

I\'ll have to think and scribble about this some more though.

[BillWiskins]

Heartily agree with all the above niceness. And still loving all of the science, even though it may as well be pictures of toasters riding about the place of the backs of pork pies for all the sense it makes to me.

AN UPDATE because I know how important it is to everyone: I made a few changes to my lander/returner homer stage, allowing the third RCS tank to be jettisoned along with the winglets. Also repositioned four thruster blocks so that they didn\'t get lost when that happens. I forgot to mention previously that below the command module and decoupler sat my lone SAS unit - I\'ve left that alone for now, but I\'ll shift it onto the landing-only part at a later date if it seems likely to help.

I made an attempt with this set-up yesterday, and whilst it was ultimately another Mun crater creation exercise, it was significantly closer to being not that. Boosting in \'stages\' as suggested finally led me to Munar orbit, although due to an intelligence/observational deficiency, I may have achived orbit some time before I noticed. I ended up a lot higher than I needed to be, and without enough fuel to boost home. Still, it\'s a dramatic improvement on previous flights...

I\'ve attached the .craft for your amusement. Technically a few extra struts would improve performance I\'m sure, but firstly, I get a LOT of lag in the Vehicle Assembly Building (as well as the frequent symmetry glitches in 0.13.1) - and secondly, watching Meredith wobble is quite a hoot. I think.

Edit: feel free to deposit Meredith in the Stock Repository, if you like.

[Kosmo-not]

BillWiskins, I took the liberty of flying your design. I was able to land it on the Mun, but was not able to return to Kerbin because the return stage had too much weight for the amount of RCS tanks and too few thrusters (forcing me to fight more against gravity).

Like an itch needing to be scratched, I had the urge to tweak the design a little to make it into a successful munar craft. I replaced the SAS with an ASAS and moved it to the stage below the return stage (so you don\'t have to lug that extra weight). I added an additional RCS tank and more thrusters. For the lifter, I put on a few struts, took away a few that weren\'t necessary, and that fixed the wobble issue. I also rigged a few fuel lines so all engines can burn and not drain the center stack before the outer ones are finished. I also staged the engines so they all fire at liftoff.

The result: An easier and quicker time getting to orbit, and a return stage that is guaranteed to get you home.

P.S.

I think this might have been my second and third attempts at landing an RCS lander, and the 1st and 2nd successful attempts.

[BillWiskins]

Well congratulations on the first RCS lander landing then, sir. I\'m pleased to have had some contribution (trivial as it may have been after your redesign).

I still stubbornly believe that it can be done with my original version, though I am completely willing to admit that that is probably foolish. I will try again, but I will also have a shot with your edited Meredith just to see how far off I was.

Re: ASAS, I had tried using one of those units before, but it\'s corrections were so violent and frequent that poor old Meredith shook her good self to death, with many explosions, and not far from the pad.

Cheers for the revisions, anyway - look forward to trying them out.

[Guest Dorsilfin]

Attaching my craft. nick named 'Munar13' Its got a piped and drop main stage, which gets you into orbit with 1 tank of fuel left on the orbital stage. this gets your burn towards Mun going, break free and start burning your landing craft fuel. I landed on mun, with less then 1/4 a tank left in my side pods, and 2 full tanks on the main body. This is a non RCS beast, so piloting skills come into play while landing. I find myself unable to do the landing without a joystick. After landing very slowly 2m/s or less you should be in 1 piece. burn the remaining fuel from the side pods, jettison them and head on home with 2 full tanks of fuel. More then enough for even huge mistakes to be made.

hope you like the design!

Built in 0.13.2

on the launch pad

On the Mun

[tarspaceheel]

Dorsil, are those radial decouplers that you\'re using as lander legs? I never even considered that possibility. How does it compare in terms of weight/stability to using winglets?

[Gojira]

Dorsil, are those radial decouplers that you\'re using as lander legs? I never even considered that possibility. How does it compare in terms of weight/stability to using winglets?

They are much, much heavier.

[Rickenbacker]

Dorsil, are those radial decouplers that you\'re using as lander legs? I never even considered that possibility. How does it compare in terms of weight/stability to using winglets?

I do the same, since I prefer the look over wings, but they\'re a LOT heavier. I really hope .14 contains some stock lander legs, would make my mun landings much easier .

[Guest Dorsilfin]

Dorsil, are those radial decouplers that you\'re using as lander legs? I never even considered that possibility. How does it compare in terms of weight/stability to using winglets?

as others have said.. heavier. but function ok. You really have to baby it down when landing tho, anything faster then 2-3m/s and you snap one or two off .. which usually is ok for landing but taking off the weight kinda gets thrown off and can be tricky.

[aFlatRabbit]

Thanks this is an awesome ship!

I was able to get to mun in a couple of tries but I finally did it. Although I still didn\'t make is back :3

[closette]

Keep trying - it took me over a week to progress from 'fatal crash on the Mun' through 'survivable hard landing on the Mun' and 'soft landing on the Mun but no return' to an eventual 'safe landing and return from the Mun'.

And sometimes I still break the spacecraft on Mun landing. >

I have attached an updated version of the craft which uses the 0.14 lander legs in place of the winglets. Use the 'G' key to deploy the legs for landing. Good luck, and check out some of the threads on this message board to see how others make it back from the Mun.