Scarecrow71

Nope. Now @AtomicTech.

Thumby

Banned for being you and not me.

It may have worked, but man it was ugly! But I appreciate the compliment!

@Superfluous J Before I start, I'd like to say that it's only been 9 days since I finished Drespollo. 9 days. It feels like I've been trying to get to other celestial bodies after that for longer than 9 days. Sometimes this game feels like an hour, sometimes it feels like several millenia. But, it is what it is. Now, with that said... Dunapollo is complete! Woo hoo! It took almost everything I had, including 2 days of reconfiguring stuff AFTER I last lost it about not being able to finish. I am sincerely hoping that, by unlocking most of tier 7, I can get to the rest of the celestial bodies out there. Except Jool; that's gonna be the last one I deal with, and I know it's gonna take everything I don't even yet know I have in me to do.

MISSION V: DUNAPOLLO I’ve wasted far too much time at this point trying to get to Eeloo and Moho, with neither one bearing much fruit other than helping me identify weaknesses in my rocket designs. Simply put, both are currently too far away from Kerbin to get there and back effectively. So we need to change gears and go somewhere else. And right now, that somewhere else is Duna. Duna is actually Kerbin’s closest neighbor, and you can pretty much get there and back with a Mun rocket. Now, the tricky part here is to get to Duna, undock, land, get back into orbit, redock…and then make your way to Ike and do all of that and then head home. I’m not going to worry about the dV map or weight requirements or anything like that any longer; I’m simply going to put together a rocket, fire it at the sky, and see what happens. I know I’ll need north of 10000 m/s of total dV, so let’s just focus on that, ok? As always, we start with a shot of the tech tree as it sits prior to doing this: I’ve currently got 294.1 science, and I could technically rummage around the KSC and get 5.9 science points to open up something on tier 7. But why? At this stage of the game, it’s too much work for too little reward. So let’s just get into design. Lander We need to design a lander that can land on multiple celestial bodies, get back into orbit, and dock with the mother ship. I’ve gone through this exercise multiple times already, and the lander designs I keep coming up with just don’t work; I end up either flipping over upon entry into Duna, or I don’t have enough fuel to get back into orbit, or the parachutes end up getting wrecked on entry, or some other random problem that prevents me from doing what I need to do. It’s getting highly frustrating, but I know that I can do this. Eventually. The Kerpollo Challenge is interesting in that we cannot just simply launch to Duna, land, and come back. Nope, we have to launch to Duna, land, get back into orbit, transfer to Ike, land, get back into orbit, then come home. And we have to leave someone in orbit around each body while we are on the surface of each body, which means we have to account for having the lander attached to the ship at some points during flight. Not a big deal, but it is something to account for. We don’t necessarily need to have only 1 lander; we do have the option of having multiple landers, one for each body. Unfortunately, this then increases mass while decreasing overall dV prior to using the first lander. It will save on return weight, but it will increase fuel need up front. I want to design this as a single lander, but all my attempts to this point have failed miserably, so I’m going to try designing a ship with a multiple lander system. So let’s get to it, shall we? The lander I’ve designed to get us onto the surface of Duna and back into orbit is this: It's showing 2749 m/s of dV here, but that’s at sea level on Kerbin; I didn’t change the dV calculator to show what it is at sea level on Duna. Why? Because I’m not going to be overly concerned about dV at this point. I know what I need to get to Duna and back, and I’m hoping that this lander is capable of getting to the surface and back. I also know that, if I can this thing back into orbit around Duna, I can transfer some fuel from the lower stages back into the lander tanks to make sure I’ve got enough to get from orbit to Ike and back. I can also, assuming I run out of fuel after getting back into orbit, use the mothership as the primary point for docking. Lot of thought being put into this, eh? I put the docking port on the bottom, which means this thing will sit on top of the mother ship. Testing shows that, even with sitting directly on the command module, the 4 spark engines won’t overheat the command module when they fire up. So I don’t need to use any tubing or anything else for separation at this point. I may come back and revisit this, however. Now we’re going to create the command module of the mother ship. We aren’t planning on bringing the lander back, but we need to have space for 3 Kerbals on the ship. I have thought about all of the pods available to me, and if we aren’t bringing the lander home, we have to make sure the command module has seating for 3. So we use the Mk1-3 Command Pod. Enough seats and cup holders for 3 Kerbals (snacks not included). So we will end up with this: The command module is pretty simple, really. It’s just a Mk1-3 with 3 radial Mk-2 parachutes, a heat shield, and a stack separator. For added stability, I’ve got some struts from the lander tanks to the command module; this will help this thing not wobble all over the place, either on the launchpad or while in flight. Return Stage (Duna to Kerbin) Sometimes it just weirds me out that I’m designing rockets backwards. Logically speaking, as a species we design things from the ground up, right? Not rockets! So we have to think backwards (as a relative term) when designing this stuff. We started at the top with the lander, then worked our way down to the command module, and now we are at the part where we gotta get home from Duna. We need enough dV and TWR to make sure that we can intercept Kerbin, do a capture burn, and have enough dV remaining to get an orbit that takes us below 70000m on Pe. If we can’t get below 70000m, we stay in space. I’ve done this several times, and the design I always come back to looks really similar to this: So, I watched several of Scott’s videos on rocket design, and I picked up a few tricks. Like the fuel lines, and how they end up providing more dV than if you don’t have them. The outer tanks will drain into the middle one, and when they are empty I can simply jettison them, gaining more dV in the process as the middle tank will stay full. This also ends up increasing overall TWR for the middle tank, going from 1.15 with the outer tanks to 2.31 once they are kicked off. That’s a Poodle under the coupling, in case anyone wants to know. And, of course, struts from the outer tanks to the coupling so that this isn’t wobbly during flight…at least until the coupling comes off. But at that point, this should be stable enough that wobbling shouldn’t be an issue. Kerbal Disclaimer: Here at the Las Kerbas Space Center, we make no guarantees that any of our craft are not “wobbly” while sitting on the launchpad or while in flight. While we take every possible precaution to insure that the craft we deliver to you is of the best quality we can muster on that day, we cannot be held liable if our engineers get distracted by the hamster cage being left open, or by snacks being left unguarded on the break-room table. Transfer Stage (Kerbin to Duna) Now comes the part where we have to design a stage to get us from LKO (~100000m) to Duna. Duna is our closest neighbor in the Kerbol system, so it doesn’t take much to actually plot an intercept. We do, however, need to account for a capture burn on Duna, as well as transferring from Duna to Ike and having enough fuel for a capture burn there too. And we also have to take all of the above weight on the ship into account for this. So our transfer stage is going to look a lot like the return stage above, just with a bigger engine for a bit of extra “oomph”. Kerbal Disclaimer: “Oomph” is a technical term that we here at the Las Kerbas Space Center put on all of our documentation. It really describes what we are trying to do with our engines, as well as sounding really nifty. Just rolls off the tongue! Told you it would look similar. The big changes here are that I’ve got 3 engines instead of 1, and the tanks are bigger. But I’m able to get ~2450 m/s of dV out of this stage, which should be enough to get me to Duna. Should be; I could very well be wrong and have to redesign this stage. One thing to note here is the Vernor engines. This thing is going to be a beast to turn once she’s in space, so we have to use something to force her to move/spin on an axis. Something I saw in a previous video was this idea to use the Vernor engines; they use RCS controls, but use liquid fuel instead of monopropellant. From what I gather, they are far more efficient than trying to use reaction wheels, so I’m going with this. Because we are using Vernor engines for spin in space, I had to turn off RCS on the Mk1-3 and on the RCS Thrusters on the lander can for now. If I didn’t, all of that monopropellant would get used up when trying to turn. I just have to remember to turn them back on when I’m docking later. Liftoff/LKO The meat-and-potatoes of the rocket is right here; nothing else happens until/unless we get into orbit. We have to have enough punch to get off the ground, and enough fuel to stay off the ground. Delta-V and TWR both increase as we burn fuel, which is good. But we have to account for the weight of the entire ship above us. Using the “Asparagus Staging” method I saw in one of Scott’s videos, we get the following: The Mission A shot of the rocket on the launchpad: NOTE: Astute observers will see that the time stamp in the upper-left corner is AFTER the time stamp shown in the end shots after landing. I reverted to launch and VAB so many times that I simply forgot to get a shot on the launchpad prior to liftoff. In the interest of being honest, I therefore put the ship on the launchpad after I landed so I could show what it looked like. The staging may be off, but this is the ship I sent to Duna/Ike. I certainly hope this doesn’t invalidate the entry; I am trying to be honest with what I launched/used. And in LKO: Got 242 m/s of dV remaining, which will get burned up rather quickly once I plot the course to Duna. Speaking of that, I have no idea what the transfer window is for this. I used the Transfer Window Planner and KAC when I went to Dres, and that worked fine. But when I did it for Duna in several trial runs, after I launched the window was still always 2 years away. So I figured if I gotta wait anyhow, I’m just gonna launch and see what happens. So now we get this for the maneuver: 4 years, 333 days, 1 hour away. Are you freaking kidding me? 4 years of fast-forwarding in space? Eeesh. Those three are gonna get hungry waiting. Well, time to quick-save and fast-forward several years. Queue Jeopardy! music right here. And the initial orbit after burn: This is pretty good, if I do say so myself. Why? Because I had to do this on my own, you see. MechJeb’s course (shown above) had the maneuver marker POINTING AT KERBIN THE WHOLE TIME! So when I fired that, I ended up sending myself into the surface like a ballistic missile. So thankfully I was able to go back to a quick-save an hour or so before the burn and re-plot the maneuver. And then do the burn on my own. And you’ll notice that I have ~1500 m/s of dV to do correction burns, which I’m going to do just after I leave Kerbin’s SOI. Before and after shots of the plotted correction burn. I aimed for 135000m when I plotted the burn, and I ended up at 102496m. That’s about as perfect as I can get without the aid of a computer. Thank goodness the fingers worked on that one! Now to quick-save and then just warp ahead to the encounter! More Jeopardy! music right about…here. That’s about an hour out from the capture burn. You can kind of see Ike on the left of Duna there; was hoping for more sunlight for that, but it is what it is. Anyhow, you can also see that I’ll be dropping the 2 outer tanks on the transfer stage during the capture burn, which is exactly what I was hoping for. That will leave ~700 m/s of dV after Duna to get to and capture Ike before transitioning back home. Assuming, of course, I can actually get the lander to Duna and back. Which I’ve been trying to do for weeks with no success. Anyhow, here’s what she looks like after the capture burn: It’s not perfectly circular, with the Pe being ~15000m less than the Ap. I could correct this, but I’m not sure I need to. That first shot you can see I’ve got Duna on the left and Ike on the right. Once again, was hoping for more light than this; maybe I can get a good shot after landing and coming back into orbit. And on that note, here goes nothing! On the surface! That went a lot smoother than I thought it would. I let the parachutes do most of the slowing the lander down; the 4 of them got this thing down to 9.9 m/s of speed. Then I just used the engines to get under 5.0 when I got close to the surface, right around 15 meters or so. She bounced a bit on landing, but the legs were wide enough to keep her from tipping over. Already did the science gathering, so now I just gotta repack the chutes and get her back into orbit. And quick-save, of course! Ready to head back to orbit, and I finally get a shot of Ike from Duna’s surface. Bill is sitting there contemplating just how small he really is…and he likes it! Hot diggity dog, I got back into orbit! With 1134 m/s of dV remaining! I gotta dock now, which shouldn’t take all that much to do. It’s the resource transfer to put more fuel in these tanks that is going to be odd for me at this point. But, docking, and then off to Ike! Docked. And I transferred some fuel to the lander for when I get to Ike. Which I plotted a transfer for! I think I might have actually left some science on Duna’s surface. With only having 1 seat in the lander, I may end up missing out on some stuff. For now, however, if I did, that’s on me, and I have to be better at remembering. Anyhow, I’m going to burn for Ike, then halfway there do some science gathering before capturing and landing! And I ended up doing a correction burn on my way to Ike; the original burn as shown above was a polar orbit, which we simply cannot have on our way to Ike if we want to get home appropriately. And here we have Bob, on EVA planting a flag on Ike, with Duna in background. I had to fast-forward a bit; I landed at night on Ike, and I wanted to make sure I got a shot in the light. The fact that Duna is rising behind the lander is just a pure bonus. Now to collect all that science and quick-save before heading back into orbit to re-dock with the mother ship. For some reason, MechJeb isn’t working like it should for docking. It will move to the starting point…but then doesn’t finish docking. I’m having to manually fire thrusters to get a bit of forward momentum after getting to the starting point, but then she just coasts in at that point. Not sure why that is, but that’s the scoop. Anyhow, gotta collect all that science from the lander and store it in the command module. Then I’m going to transfer all the fuel out of the lander back into the tanks for the mother ship, and plot a course home. So I had to transfer from Ike back to Duna. MJ didn’t like the attempt to try transferring to Kerbin from Ike, so I had to go back to Duna. That’s a lesson that I’ll put below so I don’t forget in the future…even though I keep forgetting what I wrote in #1. Yeah, that burns me all the time. Anyhow, it’s like a year until the next transfer window, so I’ll quick-save and warp ahead. The plotted burn back to Kerbin is in just under a year, and will only take 515.5 m/s of dV. I have 1698 m/s of dV in the current stage, which means I should have enough to get home. And I may not have to ditch the lander to do it. So I’ll quick-save, then warp ahead to the transfer maneuver! That correction burn puts me at a Pe of 64112m, which is perfect for the first pass. I don’t want to come in too hot and burn up on the first pass, especially after how long it’s taken me to get this far. That’s about 1 day out from Pe. Again, a shot of the Mun in the background. Why does the Mun insist upon photo-bombing my shots? And I made it! I’m home! Oh. My. Freaking. God. I cannot believe I made it to Duna, and Ike, and back. Holy. Cow. 3372.9 total science, with 3078.8 earned on this one flight. Now to head to R&D and spend a bunch. And then I’ll have to start planning for the next flight. I had so many issues with this one that I hope I can get corrected before the next one. Lessons Learned When returning to the mother ship, always make sure to return the control point back to the command module. Otherwise your maneuvers end up not working and you revert multiple times. I actually ended up jettisoning ~1000 m/s of dV upon re-entry into Kerbin’s atmosphere. I used as much as I could to slow myself down, but once I hit 20000m and the chutes weren’t showing safe to deploy, I knew I was carrying too much weight. I hate kicking fuel, but I had to do it. Proves that I over-engineered the ship…which means I’m still not thinking hard enough about what I’m doing.

@18Watt My lander looks a lot like yours, complete with the Mk1-3 command module. So I don't think I'm too far off on that. Where we differ, however is the rocket design. I continually find myself having to use solid boosters to get off Kerbin, even with the "asparagus staging" methodology (using fuel lines to increase dV on the rocket). Can you break down for me the configuration you have there? I'll be posting pictures later today, either because I failed again and need help OR, god willing, I make it home successfully. But rocket design is where I'm seriously lacking in skill, and I think a bit of help here might go a long way towards getting me to complete this before pitching the whole thing in the trash.

I don't know what I'm doing wrong with Eeloo. I spent two weeks trying to get there and back, and simply could not do it. And I'm not sure why I kept failing. So I switched to Duna...and I've been failing at that for a week and change now. And again, I don't know why. I currently have a ship head from Duna to Ike, but I'm not sure I have enough fuel to land, get back into orbit, and get home. All joking and odd configurations aside, I just don't know what the problem is or why I'm but succeeding. You're right - I did Dres, with docking, and I had never done either before. Why I've stalled out I'm not sure. I'm just...stuck. I will state that I know I'm frustrated, and I'm really trying not to lose it. And I appreciate all the help. I just see everyone else do this and wonder - out loud, as it were - why can't I? But I have learned a lot and done stuff I've never done before, such as a fuel transfer today so I have enough to land on Ike tomorrow. I'm rambling. I'll get back at this tomorrow and see where I need to make changes.

At this point, I'm not concerned about when KSP2 comes out, as long as it eventually does. All I know is that once it does come out, I'll just look straight at the developers and say...

Awesome! Don't forget to post in the Jool-5 challenge thread so you get credit for that too!

Baby Yoda is worse than Jar Jar.

My issue is lander design. I can get a rocket to Duna and have all kinds of fuel remaining to get home. But the lander? I'm stuck. I'm just...stuck. I simply.csnnot think of a decent design that works, and all my designs seem to just be a variation on the same theme. And I can't seem to find any decent, recent tutorials on lander design that don't use every part from tier 7.

And I'm ready to give up. I cannot design a rocket that can get to Duna and Ike and back. My lander always ends up being top-heavy, or I cannot get back into orbit, or something else goes wrong. I've spent the last several weeks trying to get somewhere other than Dres and I can't do it. Simply put, I CANNOT DO IT.

This is my biggest issue with the dV map -it is simply, to me, unreadable. And it is hard to figure out how much dV I need if I'm like you and hitting multiple bodies in one launch.

Banned for not having a profile pic

Here's the videos.

The funny thing is that @ManEatingApe did all of that as part of the Kerpollo Challenge. The videos are amazing

Is there a consolidated place where all the show and tells and/or dev diaries are located? I feel like I'm missing them.

Do I have to mention Antonio Banderas? Puss In Boots

Add Jay Ferguson, and now you've got Thunder Island.

Tanky