The Ultimate Challange

[herbal space program]

12 hours ago, Jetski said:

Take a look for a thread "lowest dv to moho", there are a few tricks to getting there more easily. Use Oberth leaving Kerbin (burn close) of course, but also leave SOI at an angle to save the huge inclination burn. Also an eve flyby can adjust your inclination and match velocity better. I've done kerbin-moho low orbit for under 5k, and some of the guys in the thread were way under that. If you can refuel at gilly, then use Oberth at Eve it should be doable in anything that can SSTO kerbin in theory.  Best of luck, I didn't have isru but I used a refueler in Eve orbit on my attempt

Edit: also take a glance at Nefrums Tylo lander in the Jool 5 challenge thread for inspiration. Something like 3 tons I think lol

Now this is something I know a little bit about. If you're willing to spend endless hours climbing down a ladder of Moho-resonant solar orbits, plotting one Moho encounter after another together with well-planned DSMs, you can get to low Moho orbit for as little as 1800m/s from LKO. I tried twice and gave up both times out of the sheer tedium of it. I can't recall at the moment the nym of the poster who did it, but @PLAD will remember.  Now I remember, it was @metaphor. For my part, I think just doing the strategy pictured below is pretty easy and saves you an immense amount of dV already:

Basically what you do is start at day 0 and run the clock forward until you are like 25 days past your first Eve transfer window on day 539, when you reach the Kerbin-Eve node on that side. From there, you eject somewhat diagonally and inwards (1150 m/s or so ejection burn IIRC), so you encounter Eve at its own node with Moho, about 3/4 of the way around the sun from your Kerbin ejection point. If you set up your Eve encounter correctly, you can get to a Moho-tangent orbit and do all but about 0.5 degrees of your plane change for free. From there, you can either fiddle around a whole lot to set up successive Moho encounters to slow you down, hopping down a ladder of resonant orbits, or else you can burn for around another 2000m/s at your first Moho encounter to get you from LKO-LMO for around 3200m/s all told. Edit: You can also do a hybrid version of this, in which you hop down resonant orbits until you're sick of it and then burn the rest of the way down.

 

I also posted a method a while back to get to Jool for 1377m/s from LKO, using only Mun/Kerbin encounters and DSMs:

this is not nearly as efficient as @PLAD's famous 1000 m/s route, but it has the advantage that it comes around a whole lot more often and it does save you upwards of 600m/s vs. ejecting straight for Jool. I'm sure it could also be improved upon significantly, but I think I'm done with it for now.

Edited July 2, 2016 by herbal space program

[herbal space program]

4 hours ago, Kergarin said:

That's a nice design, too  does it have enough DV left, to do the rest of the other challenge?

What made landing and starting on Laythe hard to me, was the bumpy surface, but I think you should have no problem, since your landing speed at Laythe should be extremely low. 

Yes, I think you would have to scale it up a little.  

My first design was half the size of the one in the video. It already had ISRU and landers for Eve and Tylo (even larger versions than in the video). This design was able to go everywhere... Except Moho! 

I couldn't get there with enough DV to land there, even not when starting at Gilly.

I never noticed before, how hard it is to get to Moho. I had to scale down my landers, and put on twice as much fuel tanks, just to get to Moho. 

And even with all that optimization... I finally touched down hard, with 0 oxidizer left. 

Don't underestimate moho! (if you want to go there in a SSTO that's large enough to bring two heavy landers to orbit ) 

Thanks! As pictured, the ship landed on Duna has just over 2.5km/s dV left, which I believe would be barely enough to get it back to the KSC for the K prize. As it turns out, I scrubbed the mission pictured anyway and added a bit more fuel to the plane so I'd have a more comfortable margin for that. As to Raging Sandwich's challenge, refueling is allowed so long as you make it to Jool first, so it shouldn't be a big problem. As is it can get to the Jool system without difficulty, but it will have to refuel before doing the Jool dive, because there's no trick to avoid the ~3.8 km/s burn required to get back to Laythe from the top of Jool's atmosphere.

In terms of this challenge, I definitely have a lot to think about. As to Moho, the ship as is has about 5.6km/s when fully fueled, which I reckon would be just enough to get me from LKO to low Moho orbit and back to Kerbin on one tank, according to the Eve assist strategy I posted above.  I could shave something off of this by starting from Munar or Minmus orbit, and I could also just dock a tank to the front of the ship once it's in orbit with enough  extra fuel to cover the outbound leg. Trying to figure out how to manage all the required modules will definitely be an interesting planning challenge....

 

[John FX]

12 hours ago, Just Jim said:

As far as the contract goes, I don't think so.  It appears the command pod is the key element.

Sorry, I meant for the single command pod to join with the lander and land then move to a thrust unit to transfer etc, not a pod on each lander.

[Just Jim]

2 minutes ago, John FX said:

Sorry, I meant for the single command pod to join with the lander and land then move to a thrust unit to transfer etc, not a pod on each lander.

No, I got what you meant.  I think for the contract itself, I believe you just need one command pod to visit all the worlds and moons.  As far as how it gets there, it doesn't say, so I don't see why you couldn't use multiple delivery ships or landers.  That could get creative.

[Kergarin]

To make it concrete: It's definitely like @Just Jim believes.

For Tylo and Eve I have just docked my mk1 Pod to the two landers, and I have successfully completed the contract. 

As far as I remember, the pod wasn't even the root part of my ship. (but maybe you should choose it, just to be sure) 

Since the contrac doesn't say, that you need to do a manned landing, the same should work using a probe core.

Some time ago, I've completed a similar contract, where I had to land on 5 bodys and return to Kerbin. There I was using a probe core and multiple launches, refuelling, and even exchanging the "mothership". This was counted as a success too.

[Kergarin]

16 hours ago, herbal space program said:

Now this is something I know a little bit about. If you're willing to spend endless hours climbing down a ladder of Moho-resonant solar orbits, plotting one Moho encounter after another together with well-planned DSMs, you can get to low Moho orbit for as little as 1800m/s from LKO. I tried twice and gave up both times out of the sheer tedium of it. ...

Thanks for the suggestions 

In my first version, I was trying to get to Moho, using an endless number of encounters, but  I also gave up at some point. Not at least because I had the goal, to do the whole tour in less than 20years, and because the game was running on 1/3 speed using such a large ship on my computer  (did it in 1.0.5 without 64bit support) 

[John FX]

Very much might give this one a go then. Many landers sent ahead to various bodies and an ISRU shuttle/thrust unit to move a pod/core between them.

I landed on every body years ago for the grandmaster challenge, now to repeat that AND get home...

EDIT : OK, made my shuttles to bring fuel and RCS and landers to a probe core that has a shuttle all it`s own, tested it with Moho and it can get there, land and return. Got probe back to Eve where it met up with more fuel and another lander. Will now land on Gilly to tick that off then move on to Duna then Dres. Eve can wait for last I`m thinking...

EDIT 2 : Doing a dummy run to make sure all my landers n stuff will do the job I want them to. Done Moho, Gilly, Duna, Ike and on the way to Dres where more fuel awaits. Advance landers and fuel getting to Jool now.

Edited July 6, 2016 by John FX

[John FX]

Just to update, have now landed on all bodies outside kerbin SOI except Eve, Laythe and Eeloo. The laythe attempt was doomed before launch as I failed to put the required seperator between the lander engine and a structural beam...

Once I have run the full mission as a simulation I will launch the real craft and record the mission to post.

[John FX]

Simulation run with success. Now to add science! to the probe core along with some method of relaying that science to KSC.

[Just Jim]

hey everyone,

I'm looking for a volunteer to take over running this thread and challenge.

Truth is, I've been way too busy with real life lately, and what free time I do have is spent on writing Emiko Station.  And I'm not keeping up on this challenge like I should be.  I already discussed this with a moderator, and it's no problem.

So I'm looking for someone who's been a member in good standing for a while, as well as someone who likes to take on, and maybe host, challenges already.

Thanks

[John FX]

24 minutes ago, Just Jim said:

hey everyone,

I'm looking for a volunteer to take over running this thread and challenge.

Truth is, I've been way too busy with real life lately, and what free time I do have is spent on writing Emiko Station.  And I'm not keeping up on this challenge like I should be.  I already discussed this with a moderator, and it's no problem.

So I'm looking for someone who's been a member in good standing for a while, as well as someone who likes to take on, and maybe host, challenges already.

Thanks

I`d give it a go, can`t promise to update the thread more than twice a week but it would have a caretaker. The rules seems fairly settled and there is a nice badge

I`ve not got any other challenges to take up my time and this one seems to have quietened down so it shouldn`t be loads of work.

[Just Jim]

OK, I've gotten a few replies and private messages, and after looking everyone who asked over, I've picked an experienced forum member in good standing, who has already completed a couple interesting challenges, and also recently featured in the thread of the month: @HoloYolo

Now we just have to get everything switched over.....